10 replies to this topic

[mickyh]

Looking for new thrust washers, the current ones in the block measure 0.09 inch; but this seems too big??
Any ideas?

[Cooperman]

From memory the thrust bearing standard thickness is 0.092".

What you need to do is to buy a set of standard thrust bearings and do a 'trial build', measure the end float and correct with oversize bearings as necessary. The ideal end float is 0.003" to 0.005".

Bearings come in +0.003" size, but if the crankshaft centre journal has had to be machined well down in thickness there is a +.030" set available which can be machined down to get the float exactly right.

[Spider]

I'm not sure what engine this is for but looking across all the A Series Engines, the standard Thrust Washer (per side) thickness is 0.093".  I couldn't see you needing anything thinner than these unless you were fitting a 1300 type Crank in to a (60's) Cooper S Block.

[whistler]

If you look at the back of the thrusts you might find that the stamped part number is a little proud of the surface. Just flatten that off a little.

[mickyh]

OK, it sound like I just need a standard set I hope; as I have stripped the crank and when I measured the washers that were in there I was getting 0.09-0.091, so i try a standard set and that should cure my end float hopefully.

Edited by mickyh, 07 May 2020 - 10:03 AM.

[Cooperman]

If you do a trial build with standard thrusts and find that you have more than 0.005" end float, you fit one +0.003 thrust which brings the float to be within tolerance.
If you have more than 0.008" float you fit a pair of +0.003 which again brings you within tolerance.

The maximum acceptable float is 0.006", so anything over 0.012" at trial build means it is necessary to machine down a +0.030" thrust. That is normally necessary where a crank thrust face has been damaged and it has been faced back quite a bit.

[Bobbins]

Are the oversize thrust washers available for 998 engines?

[Spider]

Are the oversize thrust washers available for 998 engines?

 

I could only see a listing on Mini Spares for standard sizes, but I'm sure if you asked, you'll find they have over sizes as well.

I check one of my suppliers and there is at least Std, 0.003, 0.015 and 0.030" sizes available. I also recall + 0.005" were available too.

[Bobbins]

For now I've ordered a standard, I'll measure the endfloat once they're in :)

[The Principal]

MED have standard and 0.003 https://www.med-engi...ust-washer-sets

[Bobbins]

For now I've ordered a standard, I'll measure the endfloat once they're in :)

All assembled with standard thrust washers and there's now 0.004" of end float.

Thanks all.