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Answered

Backfire

Dale
asked this on July 28, 2010 15:47

1988 MERC CRUISER - 350 - Getting a backfire thru the carb from Idle on up thru the RPMs - I removed the #6 plug wire from distributor and it stops the backfire.
I advanced the timing and it stops the back fire but then wont start.
Checked spark at plug seems good and swapped plug and wire from another cylinder still had backfire at #6.
150 compression on #6 cylinder.
Thinking distributor or timing chain issue, but why only back firing when #6 comes around.... hmmmmmmmmmmmm Will be coming to you for parts today based on your comments. Thanks, Dale

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Submitted from: http://www.crowleymarine.com/mercury-outboard/parts/1014_110.cfm
 

Comments

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steve maciosek

Check the valves make sure you do not have a tight intake also check the wire it may be bad thanks good luck steve

July 28, 2010 17:23.
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CBIRTLEY
Ajax_loader_small Answer

a backfire, whether thru the intake or exhaust

means the spark plug is firing

when a valve is open-intake or exhaust

i would suggest to double check your timing with a light,

an inspection inside the distributor cap

also make sure the spark plug wires are properly seperated

to prevent cross firing

July 31, 2010 06:26.
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Joe Mathos

You didn't say if you checked your fireing order.......18436572.......on most GM 350s.  Also check your cap for cracks or carbon tracking.......if you have a point system make sure that your points aren't Hanging open and that the distributor plate is level and free., Good Luck.

November 02, 2010 04:56.
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