Lister JK bearings

[flatplane8]

No other marks I can see. All 8 shells have the same number on them. I'm wondering from Alan and Bizzaeds clues of the 'G' in the circle is for Glacier. I phoned Sleeman and Hawken this morning, but they hadn't heard of those numbers. I have found that real diesels can get hold of both genuine and non-genuine bearings, which is good, just curious as to why my engine is fitted with non-lister parts (and would like to verify that they are the correct material).

[martyn 1]

Hate to be the bringer of bad news, the bearing on the left is a JK one as you know (Easily distinguishable from JP by the 45 Deg chamfer instead of the radius). The one on the right is a Lister part but the number on it is the original Lister number for a JP bearing so if you are intending to run that engine at over 1200rpm and all four of the big ends are marked 8-1 /D8 then you will need a set of four JK bearings.

 

A copy of the manual that shows the earlier number see here (This copy is pre the release of the JS/JK) click here page 85 on the control bar or 82 physically written on the page.

 

At a guess as from our previous conversations and the photos you showed me it is a JK, I would say at some point someone has fitted it with a set of the incorrect big end bearings in the past.

 

Also worth checking, I think it does from your photos but cant make it out fully, does your bottom end have the vibration damper fitted? about a 10/12 inch disc on the injector pump end of the crankshaft. The bottom end you had from us had one fitted for comparison.

Edited January 25, 2016 by martyn 1

[flatplane8]

Ah, thanks Martyn, I had a checked some other manuals I had, but didn't have one old enough. I guess it will remain a mystery as to why this engine was fitted with JP bearings, perhaps it was made on a Friday afternoon. Are there any distinguishing features of the crank to check it is in fact a JK one? The engine is stamped as a JK on the serial number plate, and has the oil fed rockers. This will perhaps also explain why one of the bearings crumbled, as even though it was a standby generator, it would have presumably been run at 1500rpm while working, and #4 cylinder is furthest from the oil pump.

 

I'll have to think what to do next, as I would want it as a 1500rpm engine.

 

Thanks all for your help!

Edited January 25, 2016 by flatplane8

[RLWP]

More likely it got fitted with JP bearings because JK ones were not available

 

Richard

[flatplane8]

Hi Richard, I would guess you are correct, possibly all they had in the parts bin, or a genuine mistake. Hi Martyn, yes it does have the vibration damper at the injector pump end, so that's positive.

[martyn 1]

Are there any distinguishing features of the crank to check it is in fact a JK one?

If your really lucky it will have the part no stamped on it,

 

13-15-608 for a JK crank

 

13-5-30 or 13-5-61 if its JP.

 

My money would be your engine has had a set of JP bearings fitted by mistake at some point in its life as the rest of it matches the JK build so I would think its fairly unlikely its not a JK crank.

[flatplane8]

Hi Martyn, I would guess so too. I'll carry on measuring everything and decide what to do, the engine isn't close to being in the boat yet as the JP3 is still working fine.

[flatplane8]

As an update, I've purchased a suitable micrometer and measured the bearing journals. I was having trouble getting the maximum diameter consistently, so hit up on the method of setting the micrometer to set measurement such as 3" exactly, and the seeing if it would pass over the journal. By stepping down small amounts at a time I determined that all the journals are 0.0015" under three inches in both planes, apart from #1 which is 0.002" under in one plane, so 0.0005" oval. From reading the data sheets I have, the journals can be up to -0.0025" of three inches and be within tolerance.

 

My next step will be to either find some JK bearings or get my current ones remetalled. I'm assuming using the second hand JK bearings from the spare bottom end is not a great idea. I did chuck them in one rod and got 0.004" clearance. :-)

 

Comments from the more experienced welcome as always.

[martyn 1]

I don't have the paperwork in from of me but I will dig out the go/no go data when I get home. max taper, ovality etc etc as the tolerances for a lot of this is not in the standard manuals. The normal maximum tolerances are in the manuals but Lister also stated in there internal documents the criteria at which they would replace when they carried out an overhaul, this is what we work to.

 

As much as I personally wouldn't reuse the old bearings from the other engine, If you give them a very detailed look over for damage and measure them up (in the rod and torqued up) and the tolerance is maintained over the full width of the journal you intend to use them on then i'm sure they would be fine.

[flatplane8]

Another update, I'm now in the job queue for JEL Bearings to get mine re-metalled, the price isn't too bad, but It'll be the end of the summer before I get them. Luckily we're not in a rush!

[flatplane8]

The bearings came back from JEL a few weeks ago, and I finally got around to checking the clearances.

 

Its fairly easy to check with the engine in bits....

 

The end result was good at 0.0025" on three of the cylinders and 0.003" on one, which I put down to my measuring....

The lead time was about 6 months, but the work itself was done quite quickly. I just sent up the old shells and one con-rod. Cost was approx. £500 for four sets. AS was mentioned earlier in the thread, quicker options were available, but the cost was about £800, so I decided to wait.

 

Don't hold your breath for the next instalment - too many projects running concurrently!

[frangar]

I shall file their details away for future use!......thanks for keeping us posted.

 

Cheers

 

Gareth