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MG Midget and Sprite Technical - Felt washer behind crankshaft oil thrower.

Hi all, just putting the timing cover on and after centralising with the crank pulley I noticed that it didn't seem to be far enough onto the end of the crank. I took it apart again and behind the oil thrower between it and the crankshaft timing gear was a thick felt washer. I've never seen this before. It's not in the Moss catalogue. Anyone know anything about this? Should I leave it on as it will get compressed when I put the crank pulley nut on and tighten it up. Or should I leave it off?

I previously had trouble with the crank pulley nut undoing itself and I know part of the cause was the lock washer was made of metal too thick to key into the recess in the crank pulley. But, I'm just wondering if the cause might be compression of this felt washer. For instance, if the nut is torqued up and locked, could the felt washer, in time, compress further causeing the original torque figure to be wrong.

It's a 1275 with duplex.

Rob. Puzzled of Wilmslow.
Rob aka MG Moneypit

I thought I should provide an image and in doing so I noticed the felt washer locates on a boss on the crank timing chain gear so can't have any influence on how far onto the crank the crank pulley locates.

Any ideas?

Rob

Rob aka MG Moneypit

Not a standard fitment.

It looks like the early 948 t/cover seal. They used a felt seal rather than a lip seal.

Maybe they were both supplied in the gasket set and the engine builder thought that it needed a home?
Dave O'Neill 2

I dont have a felt seal and im not aware of 1275 ever having any

Prop
Prop and the Blackhole Midget

Btw... the crank shaft pulley nut should have a metal washer behind the nut and and that washer has a lip on one side ... the lip is bent up and flatened agianst the nut flat... that keeps the nut from loosening

Prop
Prop and the Blackhole Midget

And so had mine, but it still undid.

The reason is the replacement lock washers are too thick. There is a recess in the crank pully that you are meant to hammer the lock washer into. This locks it to the pulley. Then you are supposed to bend up and hammer onto one (or more) locknut flats. When the metal is too thick the lock washer cannot be hammered enough to lock it to the pulley. The replacements are 30% thicker than they should be.

The lock washer I have now (supplied by Moss) I can see is too thick and has a cutout for the woodruff key. This cut-out is a bit useless anyway because the woodruff key does not protrude out of its slot in the crank pulley.

I think what they do is use a blank meant for the oil-thrower (before they shape it) as a locking washer so making the part cheaper. Unfortunately, the Moss buyers are not engineers, they are accountants.

So, in future, keep the old lock washer. No matter how much the old one is bent, it's still more use than the modern replacements.

Rob
Rob aka MG Moneypit

Moss aren't the origin of that particular one, it comes through other sources - they just happen to sell it.
But yes, they aren't to spec. I'd be interested to know if anywhere does sell the right spec.

As for bending it, the recess in the crank pulley is easily done with a pin punh, even with those thick ones. But being flat, the other way (bolt head) is extremely difficult to achieve if you haven't given it a bit of pre-bend first (as did the originals).

And it is much smaller than the oil thrower.
Paul Walbran

Use thread lock instead, no lock washer required
dominic clancy

Its a 948 timing cover felt seal, somebody down the line did a rebuild and must have thought it was used as well as later oil seal . Take it off and through it away and make sure you use a metal oil thrower in there just in case that is missing.
R Mcknight

Cant the new crankshaft lockwashers just be ground down to bend that tab easier

Prop
Prop and the Blackhole Midget

The new washers are wrong in every respect. Too thick, wrong OD, useless key slot. I binned it and re-used the old one. You could make a fresh one from some thin steel in the time it would take you to get the Moss ones to work.
Moss need to seriously review their quality control because it's not just locking washers.
Bernie Higginson

My 948 (not early) didn't have a felt washer when I dismantled recently. Reassembling, I noted that Haynes recommended lubricating it thoroughly, but I could not see where it should go, and there wasn't one in the new bottom-end gasket set anyway.

I see now that Dave's right - the para in Haynes makes it clear that this is a timing cover oil seal.

Very decorative, where you put it Rob, and what a nice fit. Glad you showed us that in time for Christmas.
Nick and Cherry Scoop

According to Moss, the change point from felt to neoprene seal was at engine number 9C/U/H37646

However, they don't mention that there were two different timing covers. The early one had an extra flange on the inside to retain the felt seal.
Dave O'Neill 2

And here's an early cover. The seal is fitted from the front. I guess originally it was probably a felt seal, but this one is neoprene.

Dave probably recognises this cover. :).

Lawrence Slater

I've left it in!!! mostly because I can't be bothered taking the cover off once again. Maybe it will dampen the timing chain rattle in a few thousand miles time??????????????

Rob
Rob aka MG Moneypit

Lawrence

I hadn't noticed that, but the felt seal is fitted between two flanges to stop it falling out.
Dave O'Neill 2

Just had a look at it Dave. Yep, it's got the flange on the inside. Maybe along with the experimental breather, the outer flange was removed to allow the later seal to be fitted.

I must get around to cutting the front out of it, for my timing chain cover oil filling/engine breather/oil sucking experiments ;).
Lawrence Slater

This thread was discussed between 19/10/2014 and 22/10/2014

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