M635CSi Chain tensioner + cutting out

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325E30
Posts: 7
Joined: Fri Apr 05, 2019 10:13 pm
Location: Holland

M635CSi Chain tensioner + cutting out

Post by 325E30 »

Hello All,

I recently bought a very nice M635CSi and I have a few issues with it;

It has the original chain tensioner with the membrane. Either one of the aluminium crush rings is leaking or something else it up, because it leaks quite a bit. Is it wise to just remove everything, clean all the parts and install it with new crush rings or would you guys advise me to put the newer style tensioner on?

Also, the engine starts fine and idles pretty good. When I hit the throttle the engine wants to cut out. I really have to feather the throttle to get it to rev up. Once it is in higher revs the engine picks up speed without a problem. What should I start with to investigate this problem?

Thanks for your help!!
marc79euro645
Posts: 56
Joined: Tue Feb 11, 2020 12:31 am
Location: pensacola

Re: M635CSi Chain tensioner + cutting out

Post by marc79euro645 »

I'd start with basics on the stumble. Is the fuel old? Try taking fuel filter off and dump gas in a jar to see. How's fuel pressure? How do the plugs look? I've had good luck with a full can of techron injector cleaner to a low tank of gas.
good luck
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