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Discussion Starter #1
here are the results from the comression test of the Fire Breathing Dragons 351C.

#8 154
#7 146
#6 146
#5 137
#4 156
#3 150
#2 150
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- and the Number 1 answer on Compression test!!!!!

O did I say that right.........O. Big ZERO!!!!!!!!!!!! nothing
Nada, Not a darn thing. I Though maybe something happened to the tester, Because the #1 cylinder was the last one I did, so I tried 3 times, then I put my finger By the hole, and could barely feel it. I took the Valve cover off and I can see the rockers going up and down with the valves. I must have one Hang of a Hole in that head gasket or what else could it be??????
Thought you guys would like to know the results.
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Oh well at least the SWMBO is taking me out to dinner tonight. I will be in the chat room after 8:30pm. tonight Eastern time

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73 351C C6 3.25 T-lock
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Other possibilities include a burned valve or a hole in the piston. Looks like you will have to pull the head to know for sure. Enjoy the evening out.

68 GT500
68 1/2 CJ Coupe

MCA# 18519
 

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there are several causes, the luckiest would be a broken valve spring or rocker arm which can be replaced without removing the head. Remove the valve cover gasket and look, and even if they look good try to press them in and compair to a good cylinder. Sometimes the inner spring can brake and you don't see it right away.

Hole in piston, cracked valve are also possible.

Motor
 

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You can put the #1 cylinder @ TDC then pressurize it with 40-50psi air (if you don't have a leak down tester then a screw in type compression tester hose with the shrader valve removed (they unscrew with a simple tool available at any auto parts store often integrated into a screw on tire valve stem cover) if you have neither of these you can have an assistant hold one of the rubber tipped blow guns in the spark plug hole.) if the leak is from the intake valve you'll hear the air at the carb, from the piston or rings you'll hear the air in the crankcase through the dipstick tube, from the exhaust valve you'll hear the air in the exhaust system. This will not save you the effort of fixing the problem but will better isolate the problem area so that you can make an informed choice on your alternatives. Any questions, post here and I'm sure someone will help.

Edit #1: Of course, #1 must be at TDC of the compression stroke for a valid diagnosis.<P ID="edit"><FONT SIZE=-1>Edited by abn on 04/13/01 08:52 PM (server time).</FONT></P>
 
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Well, I would think of a burnt exhaust valve...or a cracked piston...or knackered rings...or a cracked head...need I go on?
 
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