Engine thrust washer failure

[Quart Meg Miles]

Purely for interest has anyone else suffered total thrust washer failure?

For a couple of years I had a curious clutch problem when manoeuvering; it would clear first time but if slight engagement was made it wouldn't clear again so I often had to switch off and restart. Then a piston broke up and I was into a full reline/rebore. The previous total strip was at 170,000 and we were now at 240,000.

Removing the sump I found one of the crank thrust washers in the oil residue! Removing the crank showed the other one was badly scored and, worse, so was the crankshaft face.

I wanted to keep the crankshaft, as it was otherwise in excellent original condition, and eventually found Jim Stokes near Waterlooville who pointed me at a firm in Havant. They filled the scored area with matching metal (they were aerospace approved) and Stoke's reground the face to my dimension. Jim personally gave me some Plastigauage to measure the big end gaps and just one was 0.0003" out of spec as were the rear main bearing and one other, so no reground worth doing. Total cost in 2007 was ?350 just to repair the crank. Sorry, photos too large to display. Five years and 257,000 on the clock and everything there fine.

Anyone else had a problem in this area?

[promotor]

I've not had a failure yet (touch wood) - but looking at that thrust washer that has the grooves around its' face it appears that the wrong side of the thrust washer was facing the crankshaft. I've seen this before in engines - the crank was absolutely mullered, the block was fine, and the thrust washer was in the bottom of the sump!

Good work on the repair though - it's good to know that things can be saved, despite cost! I'm a fan of recycling/repairing where possible!

Roll on another 250,000 miles!

[Chancer]

Yep, one of them fitted the wrong way round.

I used to build loads of fast road and race engines, I am ashamed to admit that I too once made this mistake and it was on an engine for a good friend as well, I dont know what I must have been thinking, drinking or on at the time!

Still but for learning from my mistakes I would still be pretty ignorant.

[cal44]

Thanks for the pictures Quart. I am learning to put my engine back together........don't want to make that mistake.
Mike

[Quart Meg Miles]

Nobody's perfect! Curiously the washer with the wear, which matched the crank's wear, appears to be the right way around. It is on the flywheel side so took the clutch load and wore so thin that the other one fell down the gap. I don't understand the molten metal pattern on the other washer which looks as though it might have been reversed. No matter, it's fixed and thank you all for your insights.

Here's the reverse of both washers just turned over L-R:

[AussieJohn]

Would it not be the thrust washer on the front of the crank which takes the clutch load and not the flywheel side?

[Baggy2]

Don't misunderstand me this forum is great but it really can provide material to keep you awake at night. I rebuilt my engine a couple of thousand miles ago - did I put the thrust washers the right way round?............ should I rush outside, Take the engine out and strip it to find out?...........

[Chancer]

Yes!

The thrust washer at the rear of the centre main bearing web is the one that does all the work resisting the clutch thrust.

[Quart Meg Miles]

AussieJ, you're probably right in the Southern Hemi where everything is upside down but in the north it is as Chancer states, the clutch pushes the crank into the middle slab of the block. (photo too big to attach).

Baggyboy, don't fret, just wait 50,000 miles unless you're in competitions.

RTFM everybody!

[AussieJohn]

I wondered why I had a bu**er of a job putting the clutch on the crank pulley!!!!!!!