Bearings

[Nick Webster]

I'm putting this in the "natter" section because it apples to both Javelin and Jupiter. Apart from JCS what sources for main and big end bearing shells are there? I am interested to know what the guys with high performance engines are using and assuming Jowetts entering competitions are carefully assembled and stripped down fairly regularly?

Nick

[Forumadmin]

New Zealand and Australian members do modify other shells to fit . The method is well documented on JT.
I have used Perkins shells with thrust washers for 40 years getting rid of the troublesome white metal. Racing boys use separate oil feed to rear main.

[David Kemp]

Current trend is Hillman big ends, cheap & better fit than Perkins.

[Nick Webster]

David,
Would you know which model Hillman? Mind you it has to be said that in the UK Hillman spares must be getting thin on the ground these days, but nice to know anyway.
Nick

[PJGD]

Nick,
If you follow this link: viewtopic.php?f=109&t=4608&p=24858&hilit=Dingle#p30806
you will find that I posted a complete list of Clevite bearings with dimensions and part numbers, as well as materials.

Note that going by the JCL crankcase drawing in the Library, the main bearing bore in the crankcase is Ø2.394/2.393". You may need to read up on the bearing information sheets to see how much bearing crush there should be as that is an important parameter.

Philip

[Forumadmin]

I think JCS has shells as does Bill Lock and JCCNZ. Please let us know if they do not. 3 of my engines have separate thrust annular bearings in the centre web. Which means normal shell bearings are fitted all round.

[Alf Heseltine]

Would be good to know if there were any equivalent replacements of the same size so they would fit without machining.

Alf

[Nick Webster]

Philip Dingle has directed us to an interesting bearing table but this is rather leads back to the beginning rather than being a recommendation of a suitable bearing. I note though that his presentation on a Jupiter engine rebuild does mention sourcing bearings from Bill Lock - though not their actual origin.

In a similar vein the series of technical articles from JCC Australia edited by Mike Allfrey details the conversion of a Perkins bearing. However it deals with a big end bearing conversion for use as a main bearing. This is handy since it appears that the bearing is near enough the right width. However the bearing does not have a groove down the middle and while partially correcting this, not taking the groove right the way around the shell is quite unusual for a "main". There are pros and cons to this conversion which I will not debate here for fear of confusing the discussion and in any case Mike Allfrey deals with some of them in the article.

Alternatively It appears that there are Perkins Main bearings that are suitable for conversion and they are already grooved down the centre, though this is slightly narrower than the originals. Incidentally, I have seen photographs of bearings that appear to have a complete slot in them. While this may significantly aid oil supply it is my feeling that these shells might be a bit fragile and really belong in a nice stiff bearing housing, which sadly excludes the Javelin engine.

I have not seen a bearing supplied by Bill Lock so cannot comment. Can anyone come up with a photo? JCS are obtaining converted main bearings with the groove. Over the past few months I have been trying to get bearings from JCS but the first ones were loose packed and damaged on arrival. It then transpired that these were the last of their kind and further supplies would be sought from an alternative supplier. These I regret fell short of my expectations as regards quality of machining. JCS have been very patient and I hope that eventually something that matches the standard of the previous bearings might be obtained via the club.

In my original post I queried a source of bearings, not a how. As I have outlined above there is plenty of information that suggests that more than one kind bearing can be converted. My question now would be has anybody any experience or feed back on using any of the types and where did they get them?

Nick

[Srenner]

Agreed, there are no current bearing offerings that match the original Jowett bearing exactly.

Bill Lock's main and rod bearings were made by under the brand name County to the original design. Unfortunately, the rear thrust surfaces did not match the spec, requiring crank or bearing mods. I am unable to confirm who owned County at that point, but IIRC from a conversation with Bill at the time of production, they were made in India. This fits with my in period conversations with Moss Motors regarding other County produced items Moss sells, including pistons.

I bought several sets of mains and rods in std, .010 and .020. I can only speak to the sets I received, as the quality even among those sets had some variations. Coming out of the box, it was great to see modern construction of the original white bearing bearings. But they were a poor fit and inconsistent even within one bearing shell. Not too unusual for an inexpensive bearings set, but made them so much more of a hassle to use that I went back to the NZ JCC modified Perkins.

County brand bearings are now made by King Bearing in Israel. King has several levels of quality and I have used their tri-metal bearings in high rpm BMC race motors for years. Sadly, Moss sells the cheap version of these bearings, so one has to be careful. The point here is that King could produce the "correct" bearings.

The second part of the equation is the cost and what people would pay. I'm sure that was part of the math done by Mr. Lock.

Notes: 1) Tri-metal and Aluminum coated bearings have different characteristics, so in Jowett applications, we take what we can get. Ideal? Well, expedient. A good option is better than no option that requires perfection.

2) If readers are not familiar with measuring bearings shells, search how to measure bearing shells for blueprinting a motor. Surprising how much variation can be in just one shell given the tolerances.

[Srenner]

Jowett white metal bearings were babbit. This material has very good embeddebility, is quite soft and tolerant of minor misalignment. It is not capable of carrying very high loads and we know the rears had a habit of melting.

Tri-metal lining consists of sintered copper on a steel shell with a lead- indium alloy layer on top of that and finally a tin plated layer on top. These bearings have good imbeddebility, very high load carrying capacity, and are somewhat tolerant of misalignment and momentary losses of oil pressure. These are great bearings! They are rated for carrying loads of up to 10,500 psi.

Aluminum bearings consist of an aluminum bearing alloy on top of a steel back. If all conditions are perfect they work very well. They do NOT have good embeddebility, are quite hard and are very unforgiving. If anything goes wrong with the oiling system, or there is misalignment, they will fail and wipe out the crank journal. Their load carrying capacity is about 6,500 psi.

Clevite makes a trimetal bearing that is cast copper-lead and can withstand loads of 12,000 psi.

When AP Engineering who owned Glacier bought Vandervell, they started discontinuing tri-metal bearings wherever they had a Glacier substitute. They did this because the the aluminum type are much cheaper to produce.

Modern bearings are eliminating the lead content.

[PJGD]

Scott has given a good review there.

I recall that at a JCC meeting in the early 70's, Charles Grandfield recommended that we should use the Vandervell copper-lead-indium bearings rather than the Glacier equivalents where possible, based on his experience as Chief Engineer at JCL.

[Nick Webster]

Although copper lead historically solved Jowetts's bearing problems they present a problem now not least because they are being phased out! They also have corrosion problems. Although the lead was coated to protect it (nickel?) in the real world this does not last long. I recently stripped down an engine that had not been run for well over 20 years, although on the face of it there was nothing wrong. Sure enough as I expected under a magnifying glass the first signs of corrosive pitting could be seen in the shells - a sure sign they would have eventually broken up in use. Hence my looking for what's available in the modern world.

I am interested to hear information about the aluminium bearings although it seems that actually there may be no choice but to use them. It has been suggested to me that Tin alloy bearings are available but since this sounds basically like white metal, I think aluminium must have been mistaken for this. One of my concerns about the current crop of modified bearings has been the presence of burrs and high spots. This is of course difficult to deal with because normally such work would have been done on the backing before it was plated with bearing material. My concern was that these flaws could at the very least disrupt boundary layer lubrication and the bearing might wipe. Scott's informative post seems to confirm my concerns.

Nick

[PJGD]

Nick,
I think that the most comprehensive information by far on reticular tin/aluminium bearings is to be found in "Tech Notes - Part 06 - Glacier Bearings" compiled by Mike Allfrey. It can be found in the Technical Library, however having said that, I was unable to open it (or download it); not sure why not.

[Keith Clements]

Tech Notes - Part 06 - Glacier Bearings
or
HTML version

If you are a club member you will be able to view this page and then search all the (1776) pdf documents in JowettTalk.

Search for 'Glacier Bearings' produced 27 results!
This search finds the document you wanted, allows you to view it without downloading it (and so filling up your computer), and highlights the searched for terms.

[Keith Clements]

I hope I have sourced some new thrust washers for my modified blocks
Brand Glyco Manufacturer Part Number 2335638RMP, 2540203RMP, 460690RMP, A0454STD, 1212032RMP
GTIN 5010874483149
UPC 5010874483149
Reference OE/OEM Number crankshaft, FORD: 70HM6A341DA, 70HM6K302, 70HM6K302CA, 70HM6K302DA, FORD: 6018218, 6033895, 6033897, 70HM6A341A3A, 70HM6A341CA, FORD: 74TM6A341CA, A045/4STD, A045/4STD