YACT: Backfires

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
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Anyone know what hte most common cause of backfiring / misfiring are on a carburated vehicle? I am tryhing to diagnose the truck.
 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
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Originally posted by: Evadman
Timing & carbon buildup

I have the timing spot on (5* advance), at least I think. I do have some old spark plugs.. think those could cause backfiring, or interferance from the coil?
 

zerocool84

Lifer
Nov 11, 2004
36,041
472
126
ok u got the timing right then check ur plugs then clean ur carb, check the jets, clean them out, adjust it......if not.......
 

NikPreviousAcct

No Lifer
Aug 15, 2000
52,763
1
0
Backfires most commonly occur because the engine is running too rich and the fuel doesn't all get burned up in the cylinders.
 

Skiguy411

Platinum Member
Dec 4, 2002
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That reminds me....

My lawn mower back fires like 4 seconds after I turn it off. Any ideas?
 

Quixfire

Diamond Member
Jul 31, 2001
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Originally posted by: Skiguy411
That reminds me....

My lawn mower back fires like 4 seconds after I turn it off. Any ideas?
I would suggest it's running too rich.

 

Toastedlightly

Diamond Member
Aug 7, 2004
7,213
6
81
Hmm... the real question is how do I gauge how rich it is running? (no O2 sensor or anything) Maybe I need to adjust the floats..