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HunterXL565

Compression?

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Hi all,

 

I was hoping you might be able to point me in the right direction re. Bombardier 250 Military Motorbike.

 

Its a two stroke rotary valve 250cc engine, and I have recently had it running, however I can't get the rev's any lower that 3000rpm (supposed to idle at 1000rpm).

The first couple of times it started it would start easily on the second kick, however now I can't get it started unless I push start it. There is a trickle of oil coming out of the head, it looks like its coming out where the head meets the block, around where the gasket fits. Its a thick oily substance with some petrol in it. I know for a fact that the spark is good, and the plug usually comes out wet with fuel after trying to start.

 

I thought that the gasket may have gone, which would also cause the leak. Just wondering if there were any other suggestions before I remove the head and put in a new gasket which I will have to order.

 

Thanks,

 

Tom

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is the idle screw wound right out?

 

It's 1 1/2 turns out from fully in, as recommened in the manual. It sometimes starts if it is left for a while which indicates to me that it will only cut out if warmed up and expanded (gasket again?)

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Checked that as well (Y)

I've had the filter off and I can see the slide is shut, and I beleive the right amount of petrol is being delivered

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hi , two strokes :cry: , said I'd never have another one then bought the Munga :) Is the slide a flat or cylindrical one ,, because I've had the cylindrical ones where the slide pin has worn letting the cylinder to turn so the tick over adjuster pin ends up on the bottom of cylinder slide :-( just checked back your slide is shut ,, next two stroke problem air leaks in crank case IE case gaskets head gasket ,, and the best one that every one overlooks crank bearing seals , just helped a neighbor rebuild a voskod because he was having a job to get it going , He said he'd tried all sorts I said strait away crank seals ,, runs well now there replaced

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Thanks everyone, I'll start by replacing the head gasket when the replacement arrives as there is that suspicious

leak :undecided:

I somehow don't fancy taking it all to bits again to replace the crankcase seals, so i'll start with the easiest first :cheesy:

 

Cheers,

 

Tom

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