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Rapide backfires/splutters when engine braking.

danno

Well Known and Active Forum Website User
VOC Member
Hi
My Series C Rapide tends to backfire and splutter on de-acceleration/engine braking.
Acceleration is smooth with no problems and plugs are normal brown colour.
It's fitted with Lucas Rita ignition which I don't know much about hence I tend to
leave that as is.
Maybe a fuel related problem.
Any ideas/help appreciated.
Dan
 

danno

Well Known and Active Forum Website User
VOC Member
Thanks for the replies.
I had the carb's off for cleaning a while back so will check those and also the exhaust nuts.
Dan
 

Bazlerker

Well Known and Active Forum Website User
VOC Member
Spray around the intake joint area with a water bottle with the engine at a fast idle..if you hear any changes in the exhaust note - you've located the leak..You can also use WD-40, but its a lot messier...
 

Shanghai

Well Known and Active Forum Website User
VOC Member
Further to this topic.
Can anyone let me know whether using Mark 2 cams with a baffled silencer would contribute to "popping/backfiring" on the over run?
Thanks
 

timetraveller

Well Known and Active Forum Website User
VOC Member
Reference Shangai's question re. MkII cams and a baffled silence; that combination does not cause your problems but it does cause blow back from the carburettor until about 4,000 rpm due to the amount of overlap.
 

Howard

Well Known and Active Forum Website User
VOC Member
Reference Shangai's question re. MkII cams and a baffled silence; that combination does not cause your problems but it does cause blow back from the carburettor until about 4,000 rpm due to the amount of overlap.

Yep. Strange combination MkIIs and baffles. I'd suspect that was a valve timing problem
if the carburation's right.

H

Not sure that reads right. What I meant was, if you've eliminated the usual suspects of carbs, air leaks etc, and traced the problem to silencer or cams, the valve timing is the most likely cause - removing baffles is more likely to cause backfires.

H
 
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