Engine backfires

[bobp]

My Cont 65 has started backfiring, it does this when I startup, if I run it up to 15 or 1600 rpm it seems to smooth out, it well do it on either mag. After running it for awhile it stops. Any help would be greatly appreciated. Bob



Bob Pollard
Member #561
Tomah Wi

[flyguy]

Re: Engine backfires

Bob, are you talking about a loud bang out the exhaust that most people call a backfire or is it a boomp back thru the intake, like the ones that can set your carb and filter on fire?
Darryl

[Ragwing nut]

Re: Engine backfires

more than likely an intake leak. check your hoses.

[crispy critter]

Re: Engine backfires

It sounds like a sticking valve or a weak lifter. It could also be as simple as a spark plug trying to short out.

[Karl Rigdon]

Re: Engine backfires

Bob,

Most "backfire" is from a lean mixture. The lean mixture burns slower and residual combustion will exist when the valve opens. Try using carb heat soon as the engine starts and leave it on through a short warmup. Carb heat will help to enrichen the mixture. With dew or high humidity I will leave the carb heat on untill I have full throttle on take off.

Karl

[bobp]

Re: Engine backfires

Thanks to all for your quick response. I replaced the hoses on the intakes today, and no more backfire. Thanks again, Bob