backfiring threw the carburator

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lucus308
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backfiring threw the carburator

Post by lucus308 »

im at my wits end with this backfiring problem. since this problem has shown up i have check everything i can think of i changed spark plugs and wires put a new distributor cap and coil. had the carb rebuilt. shot the timming and checked the fuel pickup and fuel pump i also checked for leaks around the carburator and still cant find the problem. im running a 383 stroker with 550 hp and it has a holly 750 double pumper. everything has been great on this motor since i have bought it. i notice that it was taking more rpms to get my boat up on plane and thats when i found this issue and it only backfires in the front two barrels. any help with this will be greatly appreciated.

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yobee
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Re: backfiring threw the carburator

Post by yobee »

An intake valve is open when the cylinder fires. Go through your valves. Lots of info online how to adjust them.
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victorg
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Re: backfiring threw the carburator

Post by victorg »

X2 on adjusting the valves. If they are not right it will pop through the carb or worst wipe out the camshaft.

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HAMMERHEAD
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Re: backfiring threw the carburator

Post by HAMMERHEAD »

make sure you didnt get a plug wire crossed as well! dont overlook the simple suff.

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air-roberts
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Re: backfiring threw the carburator

Post by air-roberts »

could be a broken valve spring
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flying fish
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Re: backfiring threw the carburator

Post by flying fish »

Lean on the primaries? What your plugs saying?

Possibly one side of primary carb squirter plugged.-

plug fouling due to rich circuitry?
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lucus308
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Re: backfiring threw the carburator

Post by lucus308 »

All the plugs look like new and the plug wire are in the right spots going today to get the lash checked on the valves. Thanks for the help I'll let y'all know the outcome

gatorbait1989
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Re: backfiring threw the carburator

Post by gatorbait1989 »

Could be power valve in the carb

ddriver
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Re: backfiring threw the carburator

Post by ddriver »

do a comp. test. that may give you he answer.

lucus308
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Re: backfiring threw the carburator

Post by lucus308 »

Found the issue it was a bad rotor in the distributor thanks for the advice.

victorg
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Re: backfiring threw the carburator

Post by victorg »

Sounds like a few dollar fix. Thanks for posting what was wrong.

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Re: backfiring threw the carburator

Post by PoorboysAirboats »

Sounds to me it was a bad cap and two wires crossed! Glad we help get you back going.
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John Fenner
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Re: backfiring threw the carburator

Post by John Fenner »

So, how far did the backfire throw the carb anyway? Chuckle chuckle! Glad you fixed it!
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Re: backfiring threw the carburator

Post by :) »

I know he got it fixed but just to add, mine was doing simular things awhile back. I went through all that mentioned above then took it to someone.. ended up being bad gas and it had junked my edelbrock.. a holley and fresh gas.. what an idiot i felt like. I had tried a different carb when trying to solve it my self and had some improvement but it still wouldnt run right.. lucky for me there was only a few gallons left that i had to empty out.
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keebo
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Re: backfiring threw the carburator

Post by keebo »

lucus308 wrote:All the plugs look like new and the plug wire are in the right spots going today to get the lash checked on the valves. Thanks for the help I'll let y'all know the outcome
PoorboysAirboats wrote:Sounds to me it was a bad cap and two wires crossed! Glad we help get you back going.
HAMMERHEAD wrote:make sure you didnt get a plug wire crossed as well! dont overlook the simple suff.
Never forget the small stuff, check and check again. glad ya got it fixed.
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