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Smokey Cota 247

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Hi All

I have a 75 Cota 247 which on the whole runs very well.but smokes excessively ( even for a 70's twostroke).

I am thinking that it could be a crankshaft oil seal? The reason I think so is because when i remove the spark plug and smell it I can

smell gearbox oil.

So...assuming it is a crankshft oil seal has anyone had first hand experience of replacing one? I assume the oil seal is on the clutch side?

Do you require any specialised tools and is it something that could be done with a bit of mechanical knowledge..

Any comments would be most welcome

Regards

Hi All

I have a 75 Cota 247 which on the whole runs very well.but smokes excessively ( even for a 70's twostroke).

I am thinking that it could be a crankshaft oil seal? The reason I think so is because when i remove the spark plug and smell it I can

smell gearbox oil.

So...assuming it is a crankshft oil seal has anyone had first hand experience of replacing one? I assume the oil seal is on the clutch side?

Do you require any specialised tools and is it something that could be done with a bit of mechanical knowledge..

Any comments would be most welcome

Regards

it does sound like it's pulling the gearbox oil through the seal. i did my 325 bulto crank seals years ago, and once you got the mag off one side and the primary drive off the other, it was just a matter of unbolting a small seal housing off the main cases and popping the new seals in. would think the monty would be a similar set up.

Monty primary drive gear is on a taper which can be very difficult to separate. There are previous postings on the ways people have got the gear off. Yes the seal holder is just like a Bultaco.

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