Many Thanks David,
I am glad to find out that I am not the only one that has 'to brush off the cobwebs' on crankcases!
Today I will be putting together a Word document that I can paste into a proper reply.
Still, I am amazed at the amount of soapy water that came out of No. 1 plug well during the pressure test. See photo of rising water.
Regards for now,
Mike A.
Massive Coolant Flooding - Cylinders And Sump
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Mike Allfrey
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Re: Massive Coolant Flooding - Cylinders And Sump
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E0 SA 42R; Rover 75
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Keith Clements
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Sand Cast blocks and porous sealing
There was a small batch of sand cast blocks made by Jowett of which I have a pair.
Some Jowett engines have had minor cracks successfully sealed using a process that is now commonly used for blocks. (Not a recommendation just what I found on Google). There are many blocks with these minor cracks which show up after blocks are cleaned using chemicals or pressure washing or ultrasonics. These may have been there since manufacture but most will have developed with the stresses and strains of 70 years of abuse.
Some Jowett engines have had minor cracks successfully sealed using a process that is now commonly used for blocks. (Not a recommendation just what I found on Google). There are many blocks with these minor cracks which show up after blocks are cleaned using chemicals or pressure washing or ultrasonics. These may have been there since manufacture but most will have developed with the stresses and strains of 70 years of abuse.
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Mike Allfrey
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Re: Massive Coolant Flooding - Cylinders And Sump
Response To David Morris Comment
I have been trying to come to grips with comment that the early, sand cast crankcase sets are better, structurally than the later Series III sets.
Prior to coming to Australia to live, I did not know very much about the various changes that Jowett Cars Limited brought in over the engine’s production life. Blissfully unaware probably describes my situation back then. On discovering the Jowett Car Club of Australia, I soon understood that down here, Jowett owners had been fending for themselves since 1953/4. A number of very capable and mechanically minded club members had solved the cylinder liner sinkage problem by using a copper ring in place of the original gasket material ring. I think the rings were made by Repco for the club.
That action, virtually solved the cylinder liner ‘sinkage’ concern and, if correct shimming practices were used, 0.006 to 0.008-in., it also solved the problem of fractures at the rear of the crankcase sets, due to tightening the cylinder heads over cylinder liner lips that had protruded too much. All of this action took place in Victoria, however, the information and parts were provided for interstate members as well.
The first piece of graphic advice I was given, after arriving in Melbourne, was to always aim for a Series III crankcase set, which in my Jupiter’s case has been done, by using a crankcase set that was given to me by Neville Spawton (Midland Section). That crankcase came into Melbourne as ‘tools of trade’, under the immigration scheme in 1968. The engine that was in the Jupiter at the time was a very odd-half set! Over time, I purchased locally a Series III crankcase which had coolant jacket walls that were much less corroded. Melbourne water is very soft and used to be pure. However, when I came to rebuild an engine in 1998, I decided to abandon the local crankcase because it had weld repairs at the rear faces of the coolant jackets and due to the fact that the head gasket faces had been skimmed, making the carburettor balance pipe nip flares non-existent. Neville’s crankcase, even though the walls are thin, was the choice and still works well.
Back to the sand cast crankcase, the engine currently being worked on is E0 PB 7611, with a set number 8569, both numbers being reasonably close. In addition, there is a number 55433 stamped into both halves, adjacent to a small circle with JCL stamped inside the circle. I assume that the 55433 numbers relate to foundry records? Would this be a sand cast crankcase?
The spare Series III that has been kept is an interesting one. On the Engine Number plinth is ‘286’, just that. The matching set numbers are 26716 (which sort of fit), and just above these are the numbers 518. To me, the crankcase should have a number on its plinth prefixed E3 PE XXXXX (or even E3 SC XXXXX).
The lower wall thickness at both crankcases was measured and found to be as follows:
1. E0 PB 7611 – 0.408-in. thick, under both No. 1 and 3 cylinders.
2. 286 – 0.311 and 0.320-in. thick, under Nos. 1 and 3 cylinders respectively.
It should be noted that the Series III lower wall has a lip that extends inwards approximately 1/8-in. and thus gives the appearance of being very close to the dimension shown for the 7611 crankcase.
The last several engines that I have rebuilt have all been of the PB and PC types and, with those the oil drillings to and from the rear timing cover have been enlarged successfully.
E0 PB 7611 is the first engine I have worked on where the cylinder head surfaces of the crankcase had been skimmed. It was my intention to insert brass nip flares at the carburettor balance pipe ends, but then thought that Nature’s sealant (corrosion) would do the trick with a minimal smear of Loctite 518 as a backup.
An interesting aspect of the weld repair after the R.H.S. rear face cracked, the welder remarked how pleasant the aluminium was to weld. He showed me a modern motorcycle engine crankcase, with which he had a real hassle to weld repair it. Turned out that the casting aluminium had various metals added to make the molten metal flow more easily. Could such apply to a Series III crankcase?
Having read the article by Bill Boddy in Motor Sport magazine several times, my own leanings are towards a Series III crankcase set for durability.
Getting back to the cylinder head gasket concern, I am wondering about the larger spigot diameter cylinder liners that Bill Lock has mentioned, ‘to provide some correction at the cylinder wells’, what is going on here?
With regard to the engine currently being worked on, I have been questioning how a machine shop establishes a starting point for the machining process of skimming the crankcase joint faces prior to tunnel boring the main and camshaft bearing bores. Then, after finding warpage at the head gasket faces due to abuse or after weld repairs, how can a machinist be sure that the liner bores (wells) are at true 90 degrees to the joint faces, and to the head gasket surfaces? Could there be significant errors here?
Sadly, the machine shop that did our reconditioning jobs has gone out of the business, like most others in the Melbourne area. It is now presumed that the sump gasket face may be the only datum line.
Regards,
Mike Allfrey.
I have been trying to come to grips with comment that the early, sand cast crankcase sets are better, structurally than the later Series III sets.
Prior to coming to Australia to live, I did not know very much about the various changes that Jowett Cars Limited brought in over the engine’s production life. Blissfully unaware probably describes my situation back then. On discovering the Jowett Car Club of Australia, I soon understood that down here, Jowett owners had been fending for themselves since 1953/4. A number of very capable and mechanically minded club members had solved the cylinder liner sinkage problem by using a copper ring in place of the original gasket material ring. I think the rings were made by Repco for the club.
That action, virtually solved the cylinder liner ‘sinkage’ concern and, if correct shimming practices were used, 0.006 to 0.008-in., it also solved the problem of fractures at the rear of the crankcase sets, due to tightening the cylinder heads over cylinder liner lips that had protruded too much. All of this action took place in Victoria, however, the information and parts were provided for interstate members as well.
The first piece of graphic advice I was given, after arriving in Melbourne, was to always aim for a Series III crankcase set, which in my Jupiter’s case has been done, by using a crankcase set that was given to me by Neville Spawton (Midland Section). That crankcase came into Melbourne as ‘tools of trade’, under the immigration scheme in 1968. The engine that was in the Jupiter at the time was a very odd-half set! Over time, I purchased locally a Series III crankcase which had coolant jacket walls that were much less corroded. Melbourne water is very soft and used to be pure. However, when I came to rebuild an engine in 1998, I decided to abandon the local crankcase because it had weld repairs at the rear faces of the coolant jackets and due to the fact that the head gasket faces had been skimmed, making the carburettor balance pipe nip flares non-existent. Neville’s crankcase, even though the walls are thin, was the choice and still works well.
Back to the sand cast crankcase, the engine currently being worked on is E0 PB 7611, with a set number 8569, both numbers being reasonably close. In addition, there is a number 55433 stamped into both halves, adjacent to a small circle with JCL stamped inside the circle. I assume that the 55433 numbers relate to foundry records? Would this be a sand cast crankcase?
The spare Series III that has been kept is an interesting one. On the Engine Number plinth is ‘286’, just that. The matching set numbers are 26716 (which sort of fit), and just above these are the numbers 518. To me, the crankcase should have a number on its plinth prefixed E3 PE XXXXX (or even E3 SC XXXXX).
The lower wall thickness at both crankcases was measured and found to be as follows:
1. E0 PB 7611 – 0.408-in. thick, under both No. 1 and 3 cylinders.
2. 286 – 0.311 and 0.320-in. thick, under Nos. 1 and 3 cylinders respectively.
It should be noted that the Series III lower wall has a lip that extends inwards approximately 1/8-in. and thus gives the appearance of being very close to the dimension shown for the 7611 crankcase.
The last several engines that I have rebuilt have all been of the PB and PC types and, with those the oil drillings to and from the rear timing cover have been enlarged successfully.
E0 PB 7611 is the first engine I have worked on where the cylinder head surfaces of the crankcase had been skimmed. It was my intention to insert brass nip flares at the carburettor balance pipe ends, but then thought that Nature’s sealant (corrosion) would do the trick with a minimal smear of Loctite 518 as a backup.
An interesting aspect of the weld repair after the R.H.S. rear face cracked, the welder remarked how pleasant the aluminium was to weld. He showed me a modern motorcycle engine crankcase, with which he had a real hassle to weld repair it. Turned out that the casting aluminium had various metals added to make the molten metal flow more easily. Could such apply to a Series III crankcase?
Having read the article by Bill Boddy in Motor Sport magazine several times, my own leanings are towards a Series III crankcase set for durability.
Getting back to the cylinder head gasket concern, I am wondering about the larger spigot diameter cylinder liners that Bill Lock has mentioned, ‘to provide some correction at the cylinder wells’, what is going on here?
With regard to the engine currently being worked on, I have been questioning how a machine shop establishes a starting point for the machining process of skimming the crankcase joint faces prior to tunnel boring the main and camshaft bearing bores. Then, after finding warpage at the head gasket faces due to abuse or after weld repairs, how can a machinist be sure that the liner bores (wells) are at true 90 degrees to the joint faces, and to the head gasket surfaces? Could there be significant errors here?
Sadly, the machine shop that did our reconditioning jobs has gone out of the business, like most others in the Melbourne area. It is now presumed that the sump gasket face may be the only datum line.
Regards,
Mike Allfrey.
E0 SA 42R; Rover 75
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Keith Clements
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Liner lean and expansion.
I have been thinking about Andrew's and Philip's hypotheses. The liner lean in my opinion would be prevented by the parallelism of the head face to the block/liner face and the corresponding two liner faces. Any discrepancy would have to be taken up by the shims and head gasket. I do not think the cylindrical play of the sliding fit between liner and block is relevant as the play would increase when hot anyway.
The liner expansion (or relative contraction) is also debatable. Would the liner actually be hotter than the block anyway and so expand more?
Would the sleeve improve thermal conductivity and thus negate the desire to run hotter? This is the first time I have heard the desire to run the piston hotter to reduce oil viscosity. Many coolant suppliers use the opposite argument citing localised boiling at the liner!
I am also aware that bored out liners do get very thin, so the sleeve might have made it more rigid.
The liner expansion (or relative contraction) is also debatable. Would the liner actually be hotter than the block anyway and so expand more?
Would the sleeve improve thermal conductivity and thus negate the desire to run hotter? This is the first time I have heard the desire to run the piston hotter to reduce oil viscosity. Many coolant suppliers use the opposite argument citing localised boiling at the liner!
I am also aware that bored out liners do get very thin, so the sleeve might have made it more rigid.
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Keith Clements
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Response to Mike.
The larger diameter liners are thought necessary by Bill to compensate for having to rebore the block after welding. I do not think they have been made. I also do not think it would be necessary as a shim could be stuck to the liner.
Regarding setting up for crankshaft line boring, liner housing boring and block skimming. I have this very problem to solve on the block I have welded.
In my view you start by checking the mating faces of the two halves of the block. If there is any distortion this should be eliminated to get the faces mating using engineers' blue. If only one half of the block was welded then there is a decision to be made on where to take metal from! My prefernce would be to only work on the welded half.
The crankshaft line bore centre line needs to be determined. The liner centre lines need to intersect the crankshaft centre line. One or all four of these may have become distorted.
Drawings 5 and 11 help to understand this.
The centre line of the crankshaft should be parallel to both head faces (which may not be parallel themselves) and the head faces need to be at right angles to the liner bores. There are many variables so a process of iteration towards a compromise may be required.
First I would see if the liners slide in. Then I would see if the crankshaft turns with its shells used prior to welding . Then I would see if the head faces are parallel by setting out on the engineers' marking out bench. (I use the bed of my milling machine and the DRO system I made.) With all this information a plan of action would be decided. If all three of these elements are wrong then it would be very difficult to get an accurate result. If only one is wrong then rectification should be possible. The aim is to only remove metal caused by the expansion after welding so as not to require larger bearing shells or liners.
I have yet to learn how to go about crankshaft line boring, liner housing boring or block skimming. I might leave to the professionals even though I should have the tooling!
Regarding setting up for crankshaft line boring, liner housing boring and block skimming. I have this very problem to solve on the block I have welded.
In my view you start by checking the mating faces of the two halves of the block. If there is any distortion this should be eliminated to get the faces mating using engineers' blue. If only one half of the block was welded then there is a decision to be made on where to take metal from! My prefernce would be to only work on the welded half.
The crankshaft line bore centre line needs to be determined. The liner centre lines need to intersect the crankshaft centre line. One or all four of these may have become distorted.
Drawings 5 and 11 help to understand this.
The centre line of the crankshaft should be parallel to both head faces (which may not be parallel themselves) and the head faces need to be at right angles to the liner bores. There are many variables so a process of iteration towards a compromise may be required.
First I would see if the liners slide in. Then I would see if the crankshaft turns with its shells used prior to welding . Then I would see if the head faces are parallel by setting out on the engineers' marking out bench. (I use the bed of my milling machine and the DRO system I made.) With all this information a plan of action would be decided. If all three of these elements are wrong then it would be very difficult to get an accurate result. If only one is wrong then rectification should be possible. The aim is to only remove metal caused by the expansion after welding so as not to require larger bearing shells or liners.
I have yet to learn how to go about crankshaft line boring, liner housing boring or block skimming. I might leave to the professionals even though I should have the tooling!
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David Morris
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Re: Massive Coolant Flooding - Cylinders And Sump
Hi All,
Thanks to everyone and to Mike especially for your comments. I was interested to hear about your welder's remarks about the ease of welding the crankcase. I have heard from others that Jowett's used an aluminium alloy in later castings that had a percentage of Magnesium in the mix. I also heard that this addition spelt trouble, as the addition of the magnesium results in accelerated internal molecular corrosion. The comment made at the time of this comment was that the Series 3 ones had their death warrant built-in!
Researching the internet shows that the addition of magnesium is often seen as increasing the strength of the resultant alloy and is often used in aviation components, the use of magnesium resulting in a lighter but stronger component, compared with pure aluminium. Jowett's were closely involved with the manufacture of aviation components during WW2. However, the internet also says :-
'Magnesium and its alloys are extremely susceptible to galvanic corrosion, which can cause severe attack in the metal resulting in decreased mechanical stability and an unattractive appearance'.
It would be interesting to compare the physical weights of the early and later crankcases. I know that when Vic and I had around eight crankcase sets lying in the gloom on his garage floor, we could easily tell which ones were Series 3 or earlier from simply picking them up, without looking for the serial numbers or physical differences.
All the best,
David
Thanks to everyone and to Mike especially for your comments. I was interested to hear about your welder's remarks about the ease of welding the crankcase. I have heard from others that Jowett's used an aluminium alloy in later castings that had a percentage of Magnesium in the mix. I also heard that this addition spelt trouble, as the addition of the magnesium results in accelerated internal molecular corrosion. The comment made at the time of this comment was that the Series 3 ones had their death warrant built-in!
Researching the internet shows that the addition of magnesium is often seen as increasing the strength of the resultant alloy and is often used in aviation components, the use of magnesium resulting in a lighter but stronger component, compared with pure aluminium. Jowett's were closely involved with the manufacture of aviation components during WW2. However, the internet also says :-
'Magnesium and its alloys are extremely susceptible to galvanic corrosion, which can cause severe attack in the metal resulting in decreased mechanical stability and an unattractive appearance'.
It would be interesting to compare the physical weights of the early and later crankcases. I know that when Vic and I had around eight crankcase sets lying in the gloom on his garage floor, we could easily tell which ones were Series 3 or earlier from simply picking them up, without looking for the serial numbers or physical differences.
All the best,
David
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Keith Clements
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Aly Silicon alloy
I will strain my back. I have about thirty in my garage but only five that are any good!
My research when choosing the correct weld filler rods to use was a high silicon content.
https://jowett.net/forum/viewtopic.php? ... con#p19394
My research when choosing the correct weld filler rods to use was a high silicon content.
https://jowett.net/forum/viewtopic.php? ... con#p19394
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PJGD
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Re: Massive Coolant Flooding - Cylinders And Sump
Keith,
Looking at the differential linear expansion between the CI liner and the AL crankcase, when the coolant and crankcase is at 90°C, the liner would need to be at 170°C to have the same linear expansion as the crankcase, but this temperature difference would be highly unlikely in my view.
In the Jowett engine, the liners are likely to be over cooled since they are the first components to see the coolant from the radiator. In any normal sensible engine, the coolant has picked up heat going through the cylinder head first before getting to the liner. Yes, I am aware that there are a lot [most?] older engines where the coolant passes through the block first before the head, but several modern engine go head-first for reasons of lower friction.
Looking at the differential linear expansion between the CI liner and the AL crankcase, when the coolant and crankcase is at 90°C, the liner would need to be at 170°C to have the same linear expansion as the crankcase, but this temperature difference would be highly unlikely in my view.
In the Jowett engine, the liners are likely to be over cooled since they are the first components to see the coolant from the radiator. In any normal sensible engine, the coolant has picked up heat going through the cylinder head first before getting to the liner. Yes, I am aware that there are a lot [most?] older engines where the coolant passes through the block first before the head, but several modern engine go head-first for reasons of lower friction.
Philip Dingle
aka, PJGD
aka, PJGD
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Mike Allfrey
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Re: Massive Coolant Flooding - Cylinders And Sump
Gentlemen,
I have come to the following decision.
The engine will be dismantled to the extent that all four cylinder liners can be, if necessary be re-shimmed. Should Nos. 2 and 4 cylinders have 'lost' some protrusion (yet again), I will be using the Series III crankcase that I have here. It is my intention to use the Bill Lock cylinder head gaskets whatever they may be. It seems that there is a huge element of doubt about what they actually are. I do not know how long they have been available and it appears that my describing them as 'Czech' gaskets is totally incorrect.
I sincerely wish that the various Jowett clubs around the world would, by now, have a single policy related to the installation of cylinder head gaskets. Head gasket leakage into cylinders has been a known problem with the Javelin/Jupiter engine. Surely, in 70 years there must be a solution of some sort?
I do not believe that the cylinder liners can tilt, even though I used the term, leaning tower of Pisa in my description of what I found when the cylinder head was withdrawn. I still cannot come to understand the vast amount of soapy water that rose from the No. 1 plug well, especially after so much care had been taken during the engine's recent assembly. Such an amount of leakage, to me, was alarming.
I do not like unfounded cylinder liner protrusion specifications being bandied about. To me a bottom limit of 0.002-in. (and even that being claimed to be unnecessary) seems to verge on stupidity.
I will report on findings after a session tomorrow.
Sorry, but that is how I feel at present,
Mike A.
I have come to the following decision.
The engine will be dismantled to the extent that all four cylinder liners can be, if necessary be re-shimmed. Should Nos. 2 and 4 cylinders have 'lost' some protrusion (yet again), I will be using the Series III crankcase that I have here. It is my intention to use the Bill Lock cylinder head gaskets whatever they may be. It seems that there is a huge element of doubt about what they actually are. I do not know how long they have been available and it appears that my describing them as 'Czech' gaskets is totally incorrect.
I sincerely wish that the various Jowett clubs around the world would, by now, have a single policy related to the installation of cylinder head gaskets. Head gasket leakage into cylinders has been a known problem with the Javelin/Jupiter engine. Surely, in 70 years there must be a solution of some sort?
I do not believe that the cylinder liners can tilt, even though I used the term, leaning tower of Pisa in my description of what I found when the cylinder head was withdrawn. I still cannot come to understand the vast amount of soapy water that rose from the No. 1 plug well, especially after so much care had been taken during the engine's recent assembly. Such an amount of leakage, to me, was alarming.
I do not like unfounded cylinder liner protrusion specifications being bandied about. To me a bottom limit of 0.002-in. (and even that being claimed to be unnecessary) seems to verge on stupidity.
I will report on findings after a session tomorrow.
Sorry, but that is how I feel at present,
Mike A.
E0 SA 42R; Rover 75
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Alf Heseltine
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Re: Massive Coolant Flooding - Cylinders And Sump
Hello all
when a cylinder head is removed & the liner protrusion found to be reduced to .004 due to compression of copper liner
seal & shims, do the liners then have to be removed & reset .006 to .008 protrusion using New Zealand gasket.
If the head gasket was fitted & the liners left at .004 would it be enough to form a good seal bearing in mind the
compression of the liner bottom copper seal & shims has taken place & if new ones were fitted they presumably would
compress by this amount anyway.
If the head gasket was originally fitted using the top limit .008 then liner sinkage of .002 would still leave the gasket refit
within the instructions of .006 to .008.
Would a stainless steel spacer & sealant + shims to the liner overcome this issue, just a thought.
Alf.
when a cylinder head is removed & the liner protrusion found to be reduced to .004 due to compression of copper liner
seal & shims, do the liners then have to be removed & reset .006 to .008 protrusion using New Zealand gasket.
If the head gasket was fitted & the liners left at .004 would it be enough to form a good seal bearing in mind the
compression of the liner bottom copper seal & shims has taken place & if new ones were fitted they presumably would
compress by this amount anyway.
If the head gasket was originally fitted using the top limit .008 then liner sinkage of .002 would still leave the gasket refit
within the instructions of .006 to .008.
Would a stainless steel spacer & sealant + shims to the liner overcome this issue, just a thought.
Alf.
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PJGD
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Re: Massive Coolant Flooding - Cylinders And Sump
Mike,
This is not a solution that you will want to consider at this time, but if I ever have the opportunity this would be my preferred solution. It is to physically bolt the liner to the head so that combustion space sealing is separated from any of the other sealing functions of the head gasket. The idea would be to machine a groove in the liner top flange into which a soft copper or a Wills ring could be installed.
Three more-or-less equally spaced M4 Unbrako setscrews would pass through three holes drilled right through the water jacket areas of the head so that the liner would be attached directly to the head (with sealing washers under the head to prevent water getting into the oil). The screw threads in the liner flange would be outside of the sealing ring. Thus the head with the two liners would be an assembly, into which the piston and rods would be further assembled prior to assembly to the crankcase. A simple head gasket would still be needed to seal the water jackets etc., and a fat o-ring would be used at the bottom of the liner-to-crankcase interface.
The advantage of this arrangement is that the head studs/nuts no longer need to be torqued up to a crankcase-stretching value since they are only reacting against but not sealing against cylinder pressure. Likewise, the Unbrako setscrews are not seeing a high load either since the separating force is cylinder pressure applied over the exposed area of the liner inside the sealing ring which is only 0.4 square inches. I visualize that these set screws would be torqued up finally after the head is assembled to the crankcase and everything is settled in place.
What I am looking for is a scrap cylinder head that can be cut up top-to-bottom to identify exactly where the setscrews can be located without breaking into one of the ports. My sketch below is my best guess at where they might end up. I need to add the combustion chamber shape to this drawing to make sure that it does not extend outside of the sealing area (which it might).
This is not a solution that you will want to consider at this time, but if I ever have the opportunity this would be my preferred solution. It is to physically bolt the liner to the head so that combustion space sealing is separated from any of the other sealing functions of the head gasket. The idea would be to machine a groove in the liner top flange into which a soft copper or a Wills ring could be installed.
Three more-or-less equally spaced M4 Unbrako setscrews would pass through three holes drilled right through the water jacket areas of the head so that the liner would be attached directly to the head (with sealing washers under the head to prevent water getting into the oil). The screw threads in the liner flange would be outside of the sealing ring. Thus the head with the two liners would be an assembly, into which the piston and rods would be further assembled prior to assembly to the crankcase. A simple head gasket would still be needed to seal the water jackets etc., and a fat o-ring would be used at the bottom of the liner-to-crankcase interface.
The advantage of this arrangement is that the head studs/nuts no longer need to be torqued up to a crankcase-stretching value since they are only reacting against but not sealing against cylinder pressure. Likewise, the Unbrako setscrews are not seeing a high load either since the separating force is cylinder pressure applied over the exposed area of the liner inside the sealing ring which is only 0.4 square inches. I visualize that these set screws would be torqued up finally after the head is assembled to the crankcase and everything is settled in place.
What I am looking for is a scrap cylinder head that can be cut up top-to-bottom to identify exactly where the setscrews can be located without breaking into one of the ports. My sketch below is my best guess at where they might end up. I need to add the combustion chamber shape to this drawing to make sure that it does not extend outside of the sealing area (which it might).
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Philip Dingle
aka, PJGD
aka, PJGD
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Keith Clements
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- Given Name: Keith
- Contact:
Re: Massive Coolant Flooding - Cylinders And Sump
Philip,
Sounds like a good idea. I have about a dozen 'scrap' heads and liners and blocks so will have a look. One issue may be alignment of the bolts.
Can we find a suitable Wills ring?
Possibly put Wills ring at top and bottom of liner. Is it possible only to machine the liner with grooves and not the head and block?
One issue will be finding somewhere to place the bolts without them entering a water or exhaust or inlet tract where they would rust and prevent disassembly.
Are there any examples of this method ever having been used in a production engine?
Sounds like a good idea. I have about a dozen 'scrap' heads and liners and blocks so will have a look. One issue may be alignment of the bolts.
Can we find a suitable Wills ring?
Possibly put Wills ring at top and bottom of liner. Is it possible only to machine the liner with grooves and not the head and block?
One issue will be finding somewhere to place the bolts without them entering a water or exhaust or inlet tract where they would rust and prevent disassembly.
Are there any examples of this method ever having been used in a production engine?
skype = keithaclements ;
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Mike Allfrey
- Posts: 491
- Joined: Thu Apr 06, 2006 10:14 am
- Your interest in the forum: It is a good vehicle for getting Jowett information to others.
- Given Name: Michael
- Location: Melbourne, AUSTRALIA.
Re: Massive Coolant Flooding - Cylinders And Sump
Progress Report With Responses to Alf Hesseltine and Philip Dingle
Last night I spent some time re-checking the cylinder liner protrusion at cylinder Nos. 1 and 3. With tubes, washers and nuts just snugly holding the liners in position, The gap was a consistent 0.006-in. and the liners are within 0.001-in. of each other.
With the cylinder head placed direct on the liner lips, not thumped against them, and the head securing nuts tightened in two stages (first with wrist action, second to 20 lbs. ft.) the gap was found to be 0.002-in.
With the head securing nuts backed off by a quarter turn each, the gap was 0.004-in.
Today, with assistance, we verified paragraph one above. We then had a lengthy discussion about our findings and finally came to a decision. The cylinder head for cylinder Nos. 2 and 4 will be removed and the cylinder liner protrusion will be checked on that side. Should the protrusion be the same, after taking measurements as above, as the Nos. 1 and 3 liners, then we will push ahead installing both sides with the Jupiter style gaskets supplied by Bill Lock & Associates. This action will ensure that the same thickness gaskets are used on both sides of the engine.
Once the cylinder heads have been installed and the sealant has fully cured, the cooling system will be filled with hot soapy water and pressure tested with compressed air. The valve rockers will not be installed at this stage, to ensure each cylinder is individual.
If I were young again, I would even try installing the gaskets with a light smear of light grease on both faces!
Currently, the failed gasket has been removed from the cylinder head. After cleaning the surface, it was noted that there was water/coolant/combustion staining in the same area as that on the crankcase side of the gasket where the leak area was plain to see.
In the past, I have experienced complete success with several engines that I have assembled, it is just the last two that have given me this trouble. I think it stems from the time that the Auckland gaskets changed material used, and are thicker. Maybe those gaskets require a specification of 0.008 to 0.012-in. of protrusion?
The rear face of Nos. 2 and 4 cylinders crankcase half did fracture with just 0.006-in. protrusion though. It fractured during a period of two days, after tightening to 37 lbs. ft., but the fracture was put down to internal cracks around the upper rear head stud, not to excessive liner protrusion. See Technical Notes Part XII – Cylinder Head Stud Modification for details.
Alf, I am quite receptive to your suggestion that a stainless steel washer be used (with shims) instead of copper. I have been thinking about using a plastic washer, of the same material that is used as thrust washers in tractor and combine harvester gearboxes (manual type). They take a great amount of thrust and do not break, like some we know. Anyone out there with similar thoughts?
Philip, you have obviously put a huge amount of work into your suggestion, it looks good, but my preference would be to use a Wills Ring. Once copper settles, it tends to stay settled. I will have to have another look at Dr. Harry Brierley’s writing on that.
My main trouble is that, in the past, I have entirely trusted the parts that I have bought – that they will fit properly when the correct tolerances and specifications are observed.
Regards,
Mike A.
Last night I spent some time re-checking the cylinder liner protrusion at cylinder Nos. 1 and 3. With tubes, washers and nuts just snugly holding the liners in position, The gap was a consistent 0.006-in. and the liners are within 0.001-in. of each other.
With the cylinder head placed direct on the liner lips, not thumped against them, and the head securing nuts tightened in two stages (first with wrist action, second to 20 lbs. ft.) the gap was found to be 0.002-in.
With the head securing nuts backed off by a quarter turn each, the gap was 0.004-in.
Today, with assistance, we verified paragraph one above. We then had a lengthy discussion about our findings and finally came to a decision. The cylinder head for cylinder Nos. 2 and 4 will be removed and the cylinder liner protrusion will be checked on that side. Should the protrusion be the same, after taking measurements as above, as the Nos. 1 and 3 liners, then we will push ahead installing both sides with the Jupiter style gaskets supplied by Bill Lock & Associates. This action will ensure that the same thickness gaskets are used on both sides of the engine.
Once the cylinder heads have been installed and the sealant has fully cured, the cooling system will be filled with hot soapy water and pressure tested with compressed air. The valve rockers will not be installed at this stage, to ensure each cylinder is individual.
If I were young again, I would even try installing the gaskets with a light smear of light grease on both faces!
Currently, the failed gasket has been removed from the cylinder head. After cleaning the surface, it was noted that there was water/coolant/combustion staining in the same area as that on the crankcase side of the gasket where the leak area was plain to see.
In the past, I have experienced complete success with several engines that I have assembled, it is just the last two that have given me this trouble. I think it stems from the time that the Auckland gaskets changed material used, and are thicker. Maybe those gaskets require a specification of 0.008 to 0.012-in. of protrusion?
The rear face of Nos. 2 and 4 cylinders crankcase half did fracture with just 0.006-in. protrusion though. It fractured during a period of two days, after tightening to 37 lbs. ft., but the fracture was put down to internal cracks around the upper rear head stud, not to excessive liner protrusion. See Technical Notes Part XII – Cylinder Head Stud Modification for details.
Alf, I am quite receptive to your suggestion that a stainless steel washer be used (with shims) instead of copper. I have been thinking about using a plastic washer, of the same material that is used as thrust washers in tractor and combine harvester gearboxes (manual type). They take a great amount of thrust and do not break, like some we know. Anyone out there with similar thoughts?
Philip, you have obviously put a huge amount of work into your suggestion, it looks good, but my preference would be to use a Wills Ring. Once copper settles, it tends to stay settled. I will have to have another look at Dr. Harry Brierley’s writing on that.
My main trouble is that, in the past, I have entirely trusted the parts that I have bought – that they will fit properly when the correct tolerances and specifications are observed.
Regards,
Mike A.
E0 SA 42R; Rover 75
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PJGD
- Posts: 380
- Joined: Sun Feb 19, 2006 3:58 am
- Your interest in the forum: A Jowett owner since 1965; Javelins, Bradford, and Jupiter (current). Interested in all things Jowett.
- Given Name: Philip
- Location: Detroit, Michigan, USA
- Contact:
Re: Massive Coolant Flooding - Cylinders And Sump
Keith,
Over the next few days I will take a more detailed look at specifying the optimum Wills ring. Wills rings are made in the UK and are now owned by Trelleborg. There are other manufacturers in the US too I will look at.
While a trapped metal ring [either soft copper or a Wills ring] makes sense at the top flange-to-head joint [with groove in the liner flange only], in this proposed arrangement there will be a varying gap at the bottom between the crankcase shelf and the liner seating shoulder, both because of the differential expansion but also due to dimensional differences cylinder-to-cylinder that you will not be able to directly measure [except possibly with Plastigage or similar], a metal seal won't work and an elastomer seal will be better.
As for has this been used in production, I don't know for sure but the drawing below from Foden suggests that they have used it in their diesel engine. Then again the racing fraternity sometimes use a screwed-together liner-to-head joint; see Yamaha patent below. This is a very good but expensive solution and out of scope for us.
Over the next few days I will take a more detailed look at specifying the optimum Wills ring. Wills rings are made in the UK and are now owned by Trelleborg. There are other manufacturers in the US too I will look at.
While a trapped metal ring [either soft copper or a Wills ring] makes sense at the top flange-to-head joint [with groove in the liner flange only], in this proposed arrangement there will be a varying gap at the bottom between the crankcase shelf and the liner seating shoulder, both because of the differential expansion but also due to dimensional differences cylinder-to-cylinder that you will not be able to directly measure [except possibly with Plastigage or similar], a metal seal won't work and an elastomer seal will be better.
As for has this been used in production, I don't know for sure but the drawing below from Foden suggests that they have used it in their diesel engine. Then again the racing fraternity sometimes use a screwed-together liner-to-head joint; see Yamaha patent below. This is a very good but expensive solution and out of scope for us.
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Philip Dingle
aka, PJGD
aka, PJGD
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Srenner
- Posts: 556
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- Given Name: Scott
- Location: United States
Re: Massive Coolant Flooding - Cylinders And Sump
I have been following this thread closely as I have begun assembly of two motors this week.
One is a Series 3 with o-ring liners. These liners seat on the shoulder of the case and there is no accommodation for changing the protrusion. This one measures at .008" above the case. What to do?
My racer has a Bulletin 149 motor, so it has the same liners. For the first 20 years, I had always tried to use NOS copper/asbestos/copper gaskets as these compress enough to seal the water jackets, but some years back had to switch to the original NZ gasket, smearing the case with a thick coat of a silicone sealant and then clearing any excess from the oil return galleys. Perhaps I was lucky, but never had a gasket failure.
On the last rebuild of 758 about 8 years ago, I used Lock's steel/copper gasket as the NZ paper would bond so firmly that it took forever to scrap the damn things off. These did not compress and left a visible gap around the case. With no way to lower the liner protrusion, I made a paper gasket to seal the water jacket and used Loctite 518 on both sides of the paper. Stuck the paper gasket to the block, added the head gasket and then the head. Torqued in steps to 37.5 ft lbs and have never had an issue.
At some point many years back, I started to always put sealant on the water jacket to head gasket areas. I have tried to set the liner height at .006", although IIRC, the last one was .004" as that was the lower recommendation with the new NZ gasket.
I have always sprayed the copper shims with K&W Copper Coat https://www.amazon.com/401612-Copper-Co ... B000M8NZ8E.
Perhaps lucky here as well, as none of the builds have ever developed a liner leak.
I certainly have had a few other things go wrong on multiple motors, so always willing to learn.
One is a Series 3 with o-ring liners. These liners seat on the shoulder of the case and there is no accommodation for changing the protrusion. This one measures at .008" above the case. What to do?
My racer has a Bulletin 149 motor, so it has the same liners. For the first 20 years, I had always tried to use NOS copper/asbestos/copper gaskets as these compress enough to seal the water jackets, but some years back had to switch to the original NZ gasket, smearing the case with a thick coat of a silicone sealant and then clearing any excess from the oil return galleys. Perhaps I was lucky, but never had a gasket failure.
On the last rebuild of 758 about 8 years ago, I used Lock's steel/copper gasket as the NZ paper would bond so firmly that it took forever to scrap the damn things off. These did not compress and left a visible gap around the case. With no way to lower the liner protrusion, I made a paper gasket to seal the water jacket and used Loctite 518 on both sides of the paper. Stuck the paper gasket to the block, added the head gasket and then the head. Torqued in steps to 37.5 ft lbs and have never had an issue.
At some point many years back, I started to always put sealant on the water jacket to head gasket areas. I have tried to set the liner height at .006", although IIRC, the last one was .004" as that was the lower recommendation with the new NZ gasket.
I have always sprayed the copper shims with K&W Copper Coat https://www.amazon.com/401612-Copper-Co ... B000M8NZ8E.
Perhaps lucky here as well, as none of the builds have ever developed a liner leak.
I certainly have had a few other things go wrong on multiple motors, so always willing to learn.