Thrust washer Sizes

[Richard Crawley]

Hi Chaps,

I dont say a lot these days but feel I must respond to the post above of a recommended clearance of 8 to 12 thou on the big end bearings. Maybe things have changed but, if I had a 12 thou clearance on my big ends I would be looking for a regrind and/or a new set of bearings. 5 thou is what I regard as a maximum despite the recommendations given in the ref above .. Oil will literrally P""S out at 12 thou clearance. Plasitigauge is the correct way to go and ref the idea above .. what do you do if its too tight ... you scrape the bearings in until its correct with an engineers scraper if you know how to use one,... so it is worth the effort. You cannot just take a packet of bearings and stick them in and hope they work, I was taught to load, tighten and rotate a few turns dismantle, and scrape the high spots. Once an even bed was seen then the whole was washed and clearance measured . Did not have plasigauge in the 60's but the rods were closed with bearings in place and a blued precision plug gauge inserted to test roundness and clearnace against the crank pin (or main for that matter). Engines have changed but I dont believe 12 thou will give you a whole lot of oil pressure.

 

Its just my opinion and in the current parlence FWIW but no doubt SWFVD I suspect.

 

Kind regards

 

Well spotted Ian, must admit I missed that one. Your absolutely right, a running clearance of 8-12 thou would make it sound like some grotty old diesel; it’s total bo**ocks. First thought was someone got the decimal point in the wrong place but that puts the running clearance a bit low so I had a dig around.

 

I was unable to find data on bearing clearances specifically for the 6 (I’m sure its there but I’m probably looking in the wrong place) but I did find some data for the TR4;

 

Mains @ 0.001 – 0.0025;

B/ends @ 0.0016 - 0.0035,

 

Maximum wear/ovality measured on the crankpins & mains @ 0.001; this seems to be fairly typical data for a number of engines.

 

Your suggestion of scraping the bearings, however, is incorrect for metal backed shell bearings. Although scraping was the standard method for old white metal bearings (good old E93A & even the early 100E’s I seem to remember), you should never attempt to scrape fit metal backed shell bearing shells; if they are too tight, someone’s messed up on the machining!

Edited November 17, 2007 by Richard Crawley

[Guest ron]

Richard/Ian

The only data I can find is clearances for the Lotus Twincam crankshaft and it gives;

 

Mains .0015" to .0030"

Big End ..0005" to .0022"

 

Which agrees reasonably with the TR4 ones so 8 to 12 thou is wrong.

Ron

Edited November 17, 2007 by ron

[Richard Crawley]

Guy

It occurred to me this morning that I should have mentioned this before; don’t let the crank hang unsupported, i.e. with all the mains caps & B/end caps removed at the same time. This could lead to permanent distortion of the front & rear oil seal lips & give oil leaks after you bolt it all back up.

 

With the B/end caps still in place, the friction in the piston rings/bores will be enough to hold the crank in place while you remove the mains but I wouldn’t leave it like this, say, overnight.

[Jersey Royal]

Guy

It occurred to me this morning that I should have mentioned this before; don’t let the crank hang unsupported, i.e. with all the mains caps & B/end caps removed at the same time. This could lead to permanent distortion of the front & rear oil seal lips & give oil leaks after you bolt it all back up.

 

With the B/end caps still in place, the friction in the piston rings/bores will be enough to hold the crank in place while you remove the mains but I wouldn’t leave it like this, say, overnight.

 

Thanks Richard.

 

I now have the thrusts out and here they are.

 

Main bearing which is .020

 

 

 

Marked on the rear with a G S2021S HX

 

Would tht make it a Glacier make does not appear to have any bronze on it.

 

Have put new Vandervall washers in and check with feeler gauges all within tolerance .

 

 

 

When i come to put sump back on i have a problem with is thread sticking out should i cut it flush with my dremel ? Or better todrill it with oversize sharp bit.

 

 

Regards

 

Guy

Edited November 18, 2007 by Jersey Royal

[Richard Crawley]

It’s not ideal assessing from the photo but I’m 200% certain that that brown tinge is not the bronze backing poking through, it’s carbon stain from the oil! The bearing surface also looks untouched (no scoring) & if it had worn back to the bronze there would be nothing left of the oil grooves, which clearly still look fine!

 

So, let’s rewind here; the thrust that’s marked FRONT has no wear on it at all! Guy (sorry) but considering the previous post about the front taking all the wear, are you sure you haven’t got it the wrong way around? (or was that a blue kipper!). The one marked rear looks OK but has obviously been doing it’s job as it is showing some initial signs of wear.

 

That aside;

The journal & shell look OK but the wear pattern on the shell is not as even as I would like to see & there is a bit of a score on the far left of the shell. This may not be significant as it could be the result of **** left in the oil way (not cleaned thoroughly after regrinding) before the engine was rebuilt. There is also a mark on the journal (bottom) but it seems to be outside the edge of the bearing shell so I’ve no idea what could have caused it! Overall though I think it all looks OK.

 

Can you advise how many miles has the engine done since being rebuilt?

 

The threads look suspiciously like a Helicoil thread inserts; probably because some ham fisted idiot has previously stripped the original thread in the alloy; just dress it flush & it should be fine.

Edited November 18, 2007 by Richard Crawley

[Jersey Royal]

Thanks Richard,

 

Briefly as am in a rush, sorry, without checking the records i think all i have done in the car is about thirty thousand miles in ten years.

 

In that time i have had no internal work done to the engine. And unfortunately i dont know the service history of the engine, apart from the block numbers are correct and have some mots.

 

Oh rear is rear and front is front, strange there is ware to both but the rear seems to have more. I was suprised to see that they were not in the same condition as Maurices. I think possibly this proves that using a dial gauge on the front of pulley with everything else in tact is by no means as accurate as using feeler gauges at the thrusts.

 

Think i am happy though to put it all back together and revisit on the next engine rebuild, most probably when i change the head to unleaded.

 

Have to sort petrol in fuel though.

 

Regards and thanks

 

Guy

Edited November 18, 2007 by Jersey Royal

[Guest ron]

Guy

I've never been an enthusiast for using a dial gauge for end float and I use them frequently when machining, they are great for checking run out or setting something up a lathe but not so hot for end float.

The best I've found other than feelers and the sump off is using a telescoping gauge [snap gauge] between the pulley and the cross tube and either a mic or vernier caliper to measure. With practice if you are used to working with small sizes you can get a pretty good idea of the end float by pushing the crank forward with the clutch and pushing it back with a prybar, there should be a just a tiny amount of movement.

I would grind that Helicoil flush, it's OK otherwise, I think you'll find a lot of cars with these fitted there.

Ron

[Jersey Royal]

Thanks Ron ,

I used my dremel on it, great bit or kit, so usefull.

Sump is now back on and oil in engine.

 

 

I now have to deal with the petrol in the sump.

I have taken the pedistal off and its clear that they have been fitted side by side and obsure the hole. This was done by a local injection "specialist" when i had the car recommissioned after its three year layup two years ago . I have no idea when this problem started by have never noticed it before when i have done oil changes.

 

Anyway, i am having great difficulties in removing those pesky seals, anyone have any tips.

 

Regards

 

Guy

 

 

EDIT Panic over, managed it with long screw driver.

Edited November 20, 2007 by Jersey Royal

[Jersey Royal]

Hi ,

 

 

So to update, the thrust washers are completed sump is back on.

 

Sorted out and replaced pedistal seals.

 

 

Have got it all back together, and to my surprise she started and ran well in the garage, think one of the tappets needs further adjustment though.

Will try to take out for a run tomorrow, to check sump isnt leaking . And that i havent upset the timing too much.

 

Thanks to everyone for there help and advise.

 

Regards

 

Guy

Edited November 20, 2007 by Jersey Royal

[stuart]

Well done Guy. At this rate you will be taking on restorations in the Islands.

Stuart.

[Jersey Royal]

Well done Guy. At this rate you will be taking on restorations in the Islands.

Stuart.

 

 

Cheers Stuart,

 

I find it satisfying to be able to do things to the car, especially when they work out. Its only by doing that you learn.

 

However i would not of contemplated any off the jobs i have done on the car if it had not been for the help and encouragment from those on the Forum. The car would of been sent to the local garages where they would do their best and charge me loads of dosh, and still sometimes not get it spot on.

 

I hope that in the event of a breakdown i would be of some help to fellow TRers.

 

So thanks Again

 

 

Regards

 

Guy

[Richard Crawley]

Congrats Guy, may it be your first of many successes.

[Jersey Royal]

Congrats Guy, may it be your first of many successes.

 

 

Sorry i have to say

 

That, i checked the weep hole under the pedistal, this time with a mirror, ran up the engine, slight seepage, more seepage when engine is off.

 

So pedistal is now off again looks to me as if i the outer seal is not in far enough, according to the manual should be 18mm, so i will have to measure it somehow. Knew i should of checked it

 

Anyway have damaged it now trying to move it in slightly. Ordered new seals again.

 

Boo hoo b*m

 

Regards

 

Guy

Edited December 7, 2007 by Jersey Royal

[Richard Crawley]

Sorry i have to say

 

That, i checked the weep hole under the pedistal, this time with a mirror, ran up the engine, slight seepage, more seepage when engine is off.

 

So pedistal is now off again looks to me as if i the outer seal is not in far enough, according to the manual should be 18mm, so i will have to measure it somehow. Knew i should of checked it

 

Anyway have damaged it now trying to move it in slightly. Ordered new seals again.

 

Boo hoo b*m

 

Regards

 

Guy

It’s a shame as you were doing so well. It’s annoying when something goes wrong like that but making mistakes is sometimes the best way of learning as then you don’t make the same ones next time, just new ones! I’m still making them.

[Jersey Royal]

Thanks Richard,

 

I knew i should of checked it once it was in, but didnt, never mind.

In carpentary you measure twice and cut once.

 

Regards

Guy

[Richard Crawley]

Thanks Richard,

 

I knew i should of checked it once it was in, but didnt, never mind.

In carpentary you measure twice and cut once.

 

Regards

Guy

With all the renovation work I'm doing on this house, that quote is always at the front of my mind & I check again; I got an O level in carpentry but I still get it bloody wrong sometimes! I've just laid over 30 sq meters of quiet expensive oak flooring over 3 rooms but totally forgot that the door architrave (not fitted) had a radius on the edge & cut all the boards on 4 doors square! Now I'm having a hell of a job to fill the bloody gap & match it all up!

[88V8]

With all the renovation work I'm doing on this house, that quote is always at the front of my mind & I check again; I got an O level in carpentry but I still get it bloody wrong sometimes! I've just laid over 30 sq meters of quiet expensive oak flooring over 3 rooms but totally forgot that the door architrave (not fitted) had a radius on the edge & cut all the boards on 4 doors square! Now I'm having a hell of a job to fill the bloody gap & match it all up!

 

Perhaps you could cut the architraves off about an inch below the top of the skirting - whatever looks aesthetically right - and continue the line of the architrave to the floor by inserting an oblong block to coincide with the cutouts you've left in the floors. Solid bottom block not architecturally uncommon.

No need to make any joint between architrave & block, other than a pre-drilled oblique 2" pin, as meeting is end-grain to end-grain.

 

Also, what a heartwarming thread. So many knowledgeable helpful people.