Fan belt slips

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geoberni
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Re: Fan belt slips

Post by geoberni »

philthehill wrote: Thu Oct 28, 2021 9:05 pm
I would advise that you check the fore and aft float of the crankshaft in the block. The end float should not be more than 0.004".
The reason I advise you check the end float is that the noise of the timing marks against the pulley was not continuous so the crankshaft was moving fore and aft. It may be perfectly ok but I would check anyway.
That's a very good point Phil, the noise wasn't consistent so there must presumably be some slight movement on the crank.
0.004" is only a little over 0.1mm. :-?

With a bit of luck it's not too bad and the problem was more that the timing mark metal had been bent in.
Basil the 1955 series II

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Gerard1234
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Re: Fan belt slips

Post by Gerard1234 »

Thanks for the advice but I have a moggy from 1965
Thats a 1000 cc I believe
philthehill wrote: Thu Oct 28, 2021 9:05 pm If your engine is a 948cc unit I would recommend that instead of just fitting a new timing mark to the old cover you fit the later timing chain cover with neoprene crankshaft pulley seal. The 1098cc engine was fitted with a timing cover with neoprene seal as standard.
Some timing covers have the neoprene fitted from the inside of the timing chain cover and some have the neoprene seal fitted from the outside of the cover. Both types are acceptable and both do the job. When fitting the neoprene sealed timing chain cover you will need to fit the flat oil thrower washer and discard the cupped/concave oil thrower washer. The flat oil thrower washer is marked 'F' for front.
I would advise that you check the fore and aft float of the crankshaft in the block. The end float should not be more than 0.004".
The reason I advise you check the end float is that the noise of the timing marks against the pulley was not continuous so the crankshaft was moving fore and aft. It may be perfectly ok but I would check anyway.
philthehill
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Re: Fan belt slips

Post by philthehill »

If your engine number is prefixed with a 9 then it is a 948cc engine. If the engine number is prefixed by a 10 then it is a 1098cc engine.
The crankshaft end float is the same whether the engine is a 948cc or 1098cc unit.
If your engine is a 948cc unit it will have in all probability a felt crankshaft seal which is not very efficient.

Gerard1234
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Re: Fan belt slips

Post by Gerard1234 »

philthehill wrote: Fri Oct 29, 2021 1:53 pm If your engine number is prefixed with a 9 then it is a 948cc engine. If the engine number is prefixed by a 10 then it is a 1098cc engine.
The crankshaft end float is the same whether the engine is a 948cc or 1098cc unit.
If your engine is a 948cc unit it will have in all probability a felt crankshaft seal which is not very efficient.
The Aluminium plate on the engine has the number 10303
So i think its a 1098
philthehill
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Re: Fan belt slips

Post by philthehill »

It is the engine number prefix that will tell you the size of engine not the numbers.
Look in the wksp manual for the breakdown of the complete engine number.

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