High Compression!!
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Joined: Jul 2004
Posts: 97
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From: St Paul MN
High Compression!!
So I checked the compression on all 8 cylinders today to get to the bottom of my intake bakfire, and I found that cylinder 7 has compression 60 psi above the rest! 
The compressions test manual said it could be carbon build up. Is this accurate? Any other ideas? How do I go about fixing carbon build up?
Thanks
- Colin
The compressions test manual said it could be carbon build up. Is this accurate? Any other ideas? How do I go about fixing carbon build up?Thanks
- Colin
Burning Brakes
Joined: Feb 2001
Posts: 866
Likes: 1
From: Peabody,MA,USA
The way people get rid of carbon is to pour water down the carb. You will need to get the engine real hot. Try blocking the radiator with cardboard. With the engine hot , just trickle water into the carb and keep it running with the throttle. Just be careful not to spill too much water in at one time, it could destroy your engine.
Safety Car
Joined: Jul 2001
Posts: 3,921
Likes: 2
From: York PA
Originally Posted by 73Ken73
The way people get rid of carbon is to pour water down the carb. You will need to get the engine real hot. Try blocking the radiator with cardboard. With the engine hot , just trickle water into the carb and keep it running with the throttle. Just be careful not to spill too much water in at one time, it could destroy your engine.
Run the engine at about 2000 RPMs and use a spray bottle to spray water down the carb. If you hear the engine start to bog down more than 100 RPMs or so you are spraying too much water. Once you get it clean you need to figure out how that carbon got there.
Team Owner
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Originally Posted by stickboy
Run the engine at about 2000 RPMs and use a spray bottle to spray water down the carb. If you hear the engine start to bog down more than 100 RPMs or so you are spraying too much water. Once you get it clean you need to figure out how that carbon got there. Don't get it TO HOT normal temp is safer.... what are the PSIreadings????
Safety Car
Joined: Feb 1999
Posts: 3,630
Likes: 14
From: Fountain Hills AZ
Originally Posted by 74Thrasher
The thing is, I'm not 100% sure that it is carbon build up. All I know is that I have an intake backfire and cylinder 7 is 60 psi above the rest. Is there anything else it could be?
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Thread Starter
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Joined: Jul 2004
Posts: 97
Likes: 0
From: St Paul MN
Originally Posted by comp
Don't get it TO HOT normal temp is safer.... what are the PSIreadings????
Don't know what the normal operating specs are...
Le Mans Master
Joined: Mar 2004
Posts: 7,423
Likes: 1,458
From: Little Rock AR
Probably backfires on load, not on coast but it has been getting worse as time goes by. 
"Carknack" says: A cam lobe going down for the count, sorry!
Time for that upgrade you were wishing you could justify.
-Mark.
"Carknack" says: A cam lobe going down for the count, sorry!
Time for that upgrade you were wishing you could justify.
-Mark.
