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When thrust washers go bad

guzzul

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Thanks to a number of discussions on this forum, I thought I would check the Spit's crankshaft end-play. Not too bad, actually, at .013", but out of spec (.004"-.008"), so I pulled the oil pan and fished them out.

They were not all that badly worn, and still had some alloy on the bearing faces, but as you can see in the pic, they had started to delaminate. The rear washer is pictured on top, and it was the worst of the two.

Hopefully those little lost bits of washer got sucked up by the oil filter.
 

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Those are pretty nice, compared to some that I've seen. I've seen them half that size in the bottom of a pile of shavings in the pan. Needless to say, the crank needed work.
 
The ones I just pulled from my temp 6 engine got ya beat. My crank does need turned, but I'm just buying time with parts I have on the shelf. I'll be spending the money on the new motor.
 
Good deal.
It looks like you got to them in time.

It's an easy and cheap fix.

I have seen plenty of these cars where the thrust washers have fallen out due to wear and they are in the bottom of the oil pan.
I wish that all Triumph owners with engines from this "family" (Spitfire, Herald, GT-6, TR-6, etc.) would check their thrust washers before they do irreversible damage.
 
Has anyone documented this effort? I would like to check the thrust washers on the 4 so if a step by step is available, I sure would appreciate that.
 
The TR4 is a different engine, so I am not sure how much the thrust washer problem exists / or doesn't exist there
But, the easiest was to see what is going on with the thrust washers without taking anything apart is to push the crank pulley into the engine as hard as you can. Now have someone apply the clutch while you are watching. There should be NO visible motion. If it moves in / out, there is a problem. You could use an indicator / feelers etc if this makes you feel better, but if you can see motion you need to take more action, if you can't see any motion you are basically safe.
 
To change them, you drop the oil pan. They are very easily accessible. I used a small screw driver to push one side. Once the other side is visible, I grabbed it with needle nose pliers and pulled it out. Take note of which way each of the washers face.
While you are in there, you can inspect your bearings and oil pump and pan.
Follow your manual for proper torque settings for assembly.
 
Those are more or less what ours looked like when I replaced them. I could get a little bit of play in the crank.

Maybe it was jsut me, but it seems the how-to documentation for this job seems to be lacking... but once you actually get in there it's relatively self-explainitory...

I've seen the results of failed washers in Britsih Miles' back lot... blocks with big hoels in the side...
 
aeronca65t said:
I wish that all Triumph owners with engines from this "family" (Spitfire, Herald, GT-6, TR-6, etc.) would check their thrust washers before they do irreversible damage.
That's good advice.

As others have noted also, these weren't too bad. The reason I checked them in the first place is because of what I had heard here about tw's falling out and totalling the crank. Given the relatively small amount of play (.013") I was pretty sure they were both still in place. What surprised me is how they were deteriorating. I had just expected them to be worn down, i.e. a little thinner, not breaking apart.

As you say, this is cheap preventive maintenance.
 
TR4 said:
Has anyone documented this effort? I would like to check the thrust washers on the 4 so if a step by step is available, I sure would appreciate that.
As noted by others, it is not a difficult fix. Paul Tegler has a pretty good writeup for Spitfires, and I believe it should be pretty much the same for TR's. Check this link:
https://www.teglerizer.com/triumphstuff/thrustwashers.htm

I found getting the sump off was the worst part of it. The PO had used some kind of adhesive on the pan gasket, and it took a certain amount of cursing to get it to move. It's just a messy place to work anyway.

Once the pan is off, the rear bearing housing is easy to get at. Just take out the two bolts and give it a tug or a bit of a pry and it should come straight down. It sticks on the crank pretty tight. Try not to dislodge the bearing mounted in its housing, and make a note of which side of the housing faces the front of the car, so you can make sure the main bearing goes back in the right way round.

The manual talks about rotating the crank to get the thrust washers out and to reinstall them, but I didn't need to do that. You can see the ends of the washers clearly with the main bearing removed. I just used a spring hook to poke one side of the washer up, and it naturally rotates itself around the crank and out. To get them the last bit out, I used one of those magnets-on-a-pointer to just grab it and rotate it out off the crank.

You should use a micrometer to measure the washers that come out. If you add up these measurements, plus the measurement you got when you used the dial gauge to check end play, you should have a pretty good idea of the total possible axial movement of your crank. This will give you an idea of whether you need standard size replacement washers or oversize. Standard washers are .090", and you can get oversizes of 5-10-30 thousandths, maybe others.

My total endplay was .195" with no washers. I allowed for .005" endplay (spec is .004"-.008" for my Spit) to give me .190, so I planned to use two 5-thou oversize washers. I ordered both standard and 5-thou oversize. You need to measure these with a micrometer too, because they are not exact. I found the 'standard' size actually measured .092+" and the oversize .096+". So I wound up installing one standard and one oversize, that's all I could get in there. As it turns out, my end-play now measures .005" so go figure.

When you reinstall, some manuals show the oil grooves pointing the wrong way. Make sure you install the new ones with the oil grooves facing *away* from the crank bearing (i.e. the rear washer will have oil grooves facing the rear of the car, the front washer grooves will face the front of the car).

I installed the rear one first. Push back on the crank to give yourself maximum clearance, and it should just slip right in. Remember to lubricate it with engine oil or Lucas oil before installing. Once the back one is in, press your clutch to give you maximum clearance for the front washer and install the appropriate size. You should have just enough clearance that you can push one end in and just rotate it into place.

Lubricate the main bearing, pop it into place and torque it up. Done. Restest with a dial gauge to make sure while you still have the pan off.
 
TR4 said:
Has anyone documented this effort? I would like to check the thrust washers on the 4 so if a step by step is available, I sure would appreciate that.
The thurst washers on a TRactor motor (TR4 motor) are practically bullet-proof, so no need to worry, IMO. The design is different, with twice the bearing area of the later designs. If you just change them whenever the main bearings need changed, you'll never have a problem, IMO.

Paul's instructions are right-on, as usual. However, IMO it's not really a requirement to use a dial indicator, so I wouldn't buy on just for this. You can easily tell by eye if the thrusts are getting bad enough to fall out (except of course that the TRactor motor keeps them trapped so they can't fall out).

OTOH, a dial indicator can be a handy tool to have around, and Enco usually has them on sale for under $25.
 
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