SECTION ENGINE REBUILD

[Drummond Black]

SUNDAY 27th FEBRUARY 2011
An optional Technical Meeting was held today to which six members attended. The flywheel, re-faced by Bob Mackay, had a new ring gear shrunk on ( Top marks to Ruby's fan assisted oven) and locked in position with four M10 countersunk socket screws located around the rim. It was then bolted to the rear of the crankshaft. A pair of rocker shaft assemblies had been prepared by Dave Thomson who also cleaned and fitted new lock nuts to a selection of push rods. DB has a small jig that checks push rods for straightness. We selected 8 rods out of 11 prepared ( three were shown to have a slight bend in them ). The push rods were fitted, followed by the rocker shaft assemblies. Copper washers were used to seal the oil banjo faces. The valve clearances were adjusted using the zero backlash method. A pair of exhaust manifords had been prepared by DB. The offside manifold was a good casting that had a broken lug. This was expertly repaired using arc welding by DB and the gasket faces re-machined before fitting. Jack Kirk fitted a painted set of tappet chest covers followed by Jim Spalding fitting the carburettors and operating mecanism.

The power unit is now taking shape and once again Martin recorded the salient points. Next Sunday will be the " Big One " as we hope to have it ready to fit to the test bed ( We have one MAJOR headache though - we are not sure if we can afford the petrol to start it !!!!!!!!!!!!!!!!!!!!!!!). Watch this space.

Drummond

[Alastair Gregg]

Surely being nearer the source of the petrol up there, it should mean a Scotsman could do a deal

Seriously you know you have the international Jowett community clamouring for even pre production copies of Martins video. Keep on keeping on Gentlemen, and of course Ruby and her oven.

[Drummond Black]

Sunday 6th March 2011

A more relaxed approach took hold of our crew today as the final items were fitted to our project. The oil pump had been rebuilt, tested and fitted to the unit prior to the meeting to speed up progress. But don't worry, nothing will be missed as we intend to treat this item as separate chapter and video data will be released later. The same will be available for the rebuilding of the cylinder heads. The members present on Sunday were shown a very simple method of setting the adjustable oil pressure release valve, a point which was well accepted. One other interesting point was an effective method of charging the rear crankshaft spigot bush which accepts the clutch shaft. This is a sintered oilite bush and is usually purchased dry and requires to be filled with oil. The first task is to remove all the air and replace it with oil. a very simple method of completing this task is to make a small vacuum chamber out of a STRONG jar which has a strong steel or alloy cap. Drill a hole on the cap and attach a small length of copper tube which must have a perfect seal. attach the tube via a reinforced plastic tube to a vacuum pump. ( one that you use to check the balance pipe seals ). Half fill the jar with oil and drop thhe bush into the oil. Seal the cap and decompress the jar to no more than 20 ins of mercury. During this operation you can watch the air be removed from the bush. Keep it in a decompressed state until all the air has been extracted from the bush. Make sure that at all times the bush is totally submersed in the oil. When you release the vacuum the bush will suck in oil. The same method can be used to charge the water pump bearings. But back to the engine, we got the front timing cover fitted, special attention was paid as to the sealing of the 1/4 BSF bolts that go into the wet oil areas. The front pulley wheel was then fitted. We then turned the engine over on the stand to fit the baffle plate and the sump. A rubber gasket was used to seal the sump. The petrol system was then finished followed by the rocker covers. The unit had finally been completed just as Ruby summoned us all for eats.

So a plan for the next meeting took shape over snacks. We will remove the unit from the assembly stand and fit it onto the test bed. The auxilluary equipment is already ready to be attached and then the " START UP". We will not forget to add oil. So next, and final meeting of this project will take place on Sunday 27th March. Hopefully a few beers will be downed in celebration. Lets be positive............. KEEP WATCHING FOLKS.

Drummond

[Tony Fearn]

KEEP WATCHING FOLKS.
A rubber gasket was used to seal the sump.
Drummond

It's all very interesting even for a committed Pre-War(ian), but won't rubber perish if oil and petrol get to it?

Tony.

[Drummond Black]

Tony,
The Gasket is made from Nitrile Rubber ( NBR ) Nitrile rubber is a synthetic rubber with varied properties depending on its polymer composition of acrylonitrile. it is generally oil & fuel resistant and it used in hoses, seals and gaskets plus other applications. It has been around for about 60 years. Definately worth trying in place cork or gasket material.

Drummond

[Drummond Black]

Section Engine in Frame 002 (2).jpg

[Forumadmin]

Note Project B team the engine stand we need!

[Tony Fearn]

It has been around for about 60 years.

Today I've been around for 67 years! Long may it continue.

Of course I knew that it would have been nitrile rubber, but others might not have done(??). So it's now in the public domain.

I'm impressed with the engine stand. Is it a commercial item, or a jig put together by your goodself?

Have there been technical drawings of it that others might copy for their own use?

Tony.

[Jack]

It has been around for about 60 years.

Today I've been around for 67 years! Long may it continue.

Of course I knew that it would have been nitrile rubber, but others might not have done(??). So it's now in the public domain.

I'm impressed with the engine stand. Is it a commercial item, or a jig put together by your goodself?

Have there been technical drawings of it that others might copy for their own use?

Tony.

Hi Tony,

I saw a nice design for an engine stand in the gallery, but now can't find it for the life of me. Perhaps worth a search, unless Drummond has got drawings for his design (from the photo it looks very similar so could have been from the same plans I have seen)

We are going to need something similar for our impending rebuild(s) - I will try and have another search this evening.

Jack.

[Jack]

My patience finally held out - Drummond can you advise if you used this link, or if it is of your own design?

This is the one that Phillip Dingle has drawn up:

http://www.jowett.net/forum/viewtopic.p ... tand#p8337

Jack.

[Drummond Black]

This was not a copy of any other stand, but is a Scottish Section design. Roger, from the Isle of Skye, made the main frame and I made the engine holding frame, from a sketch by Roger. We know it can be improved and this is under consideration. It can be rotated to any position making assembly a lot simpler. We may be prepared to sell the manufacturing rights. !!!!!!!!!!!!!!!!!!!! I will dig out the drawings we worked from.

More later

Drummond

[ksf996]

You're in demand, Drummond! Can you please make sure that the final edit does include any comedy injuries of the rebuild... after all, team SC shared theirs on the internet, I feel it's only fair that the Scottish contingent continue the tradition

Funnily enough none of the greasy gang have been injured yet (could be tempting providence here), but during the final torque down eyes were shut and most of us were on the garage floor or behind solid objects. Dont think it was filmed at least I hope not. DT ksf996.

[Drummond Black]

SUNDAY 27th MARCH

Around 12 noon 9 members helped to transfer the " Project Engine " fron the Assembly frame to the awaiting test bed situated in the garage area. Prior to being placed on the test bed the clutch pressure plate and friction plate were fitted. The assembly frame is now going to be modified to allow this function to be completed in position as currently not enough room is available to allow access for the clutch input shaft to line up the friction plate. This completed the dummy gearbox was bolted to the rear of the bell housing and the total assembly was placed on the test bed. After an hour all the auxillary items had been fitted, ie, water pump, dummy dynamo, radiator and hoses, starter motor and finally the distributor was fitted and the engine stactically timed ( Well - roughly as we later found out ). Water, with a smll amount of summer coolant to combat any corrosion , was added first with the sump plug removed. A few minor leaks were encountered which were rectified, however one small leak from head stud number 10 was seen be weeping from the lead wire seal. It was agreed to leave the rocker covers off and rectify this during the re-torqing of the NZ head gaskets. The radiator was totally filled and left to stand for a bit before checking the sump plug recess for signs of internal leaks. None werre detected and with the magnetised sump plug replaced the system was filled with oil. With the start plugs removed the engting was turned over using the starter motor to prime the oil galleries. It took about 20 seconds to show a good 70 psi on the oil pressure gauge.( Wow - and no sign of any oil leaks. The rocker assembly banjo nuts were slackened very slightly to ensure that we had oil pressure going to the rocker shafts. And boy there definately was a good oil flow here, says he as he mopped up the spray !!!!. So now we have oil pressure, a minimal of water drips, and all we required now was fuel. A pipe from the mechanical pump was placed into a can of unleaded and the fuel system was primed. Spark plugs were all replaced and the button was pushed. We had to add Sandra & Bills booster pack to spin it fast enough as our battery leads were over 7 metres long being fed by the Rover battery in the driveway. A bit of resistance was encountered followed by fuel spurting out of the RH carburettor. Thinking caps on lads, and the suggestions came thick and fast. It pays to take a step back and analyse situations a nd it was eventually agreed that there could be more than one fault. Ranald Mackay's observation was that it sounded as if the ignition was rather advanced. Was the float chamber needlle valves working correctly ????. Stage one - we dropped the float chambers and replaced the valves and then decided to reset the ignition timing which we found to be nearly 40 degrees advanced. ( Well it was only set roughly !!! ). This was rectified to TDC and the button pressed again, and YES YES it fired up and ran until BOTH carbs spewed fuel all over the place. QUICK SWITCH OFF was called for, and back to the think tank. Needle Valves checked again Was the fuel pump delivering too much pressure ?? This was a proven pump !!. BOTH CARBS - What is the common denomenator ?? All agreed it pointed to the fuel pump. Bill P played about with it then !!!!! WHAT HAD BEEN REPLACED ?? The oil pump drive shaft - YES. Should that affect the pump, Doubtful !! then the short operating shaft that is pushed out by the oil pump excentric, YES - Drummond had made a new one out of polished silver steel. was it the correct length. No sample was available to check it against ? So the fuel pump was removed, the shaft was withdrawn from the front timing case and measured, replaced again and protrusion checked. Yes it looked a bit longer than required, So it was removed, taken to the lathe and shortened by .060. An extra gasket was fitted rather than remove too much material. The pump was then replaced and the engine fired up again.

This time the unit ran sweetly, no fuel spillage whatsoever. So a learned here. Oil was very slowly dripping from the rocker shafts GOOD, so the covers were replaced. A bit of carb adjustment to balance the tickover and the unit was allowed to heat up. The strobe was connected and the ignition timing was finely adjusted which slowed the tickover down a shade. The exhaust output was carefully listened to !! yes - A NICE EVEN BEAT. A very slight tappet rattle could be detected, however as they had been only roughly set, this was accepted.

The engine temperature was allowed to reach 75 degrees C and to stabilise around this temperature. The unit was then switched off and the rocker assemblies were removed to allow the New Zealand head gaskets to be re- torqed. It was very noticeable how much take up was required as the cylinder head nuts, which had been taken up to 38 foot pounds during initial assembly, were now turning at a torque spanner setting of 30 foot pounds. All the cylinder head nuts were re-torqued back up to 38 ft lbs and the rocker assemblies replaced. AND WE THEN LEFT IT TO COOL OVERNIGHT. !!!!!!!!!!!!!!!!!

The tappets will be reset tomorrow when the unit is totally cold. The assembled were extactic at the result after a year of learning, preparing parts, engaging in the assembly, helping overcome difficulties en route, however what has definately come out of this project and was shown if full today can only be described as follows TEAMWORK

I would like to take this oportunity to thank every Scottish Section member who involved themselves in this learning project. All agreed today that it has really been worthwhile. OK, the engine is now a running unit but there is still parts that still require to be filmed as modules. ie The oil Pump rebuild, renovating of the cylinder heads, plus a few bits that we will recognise as Martin & myself edit the 30 plus hours of video - WHAT A THOUGHT !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

I would also like to take this opportunity to thank all our Jowett Club supporters who encouraged us to create a DVD ( well hopefully ) and supplied messages of goodwill over the term of the project. We felt that this helped turn it into a " Club Project. " THANK YOU WORLD OF JOWETT "

The engine will be run on the test bed for a few days to allow it to be adjusted and settled in. So please keep watching the "TARTAN ENGINE"

Drummond