My #4 cylinder has no compresion, the other 5 cylinders tested inbetween 85% to 100%.<br />What could cause this, how hard is it to diy fix, and is it worth fixing?
First step is a factory manual. Next thing is to remove the head and check the condition of the head gasket (I hope it's that simple). Many things can cause this and the gasket is common and easy to replace. If it is not the gasket, rotate the motor manually and check for complete stroke and cylinder wall condition. Post back and we can give better help with the reported info.<br />Good luck
Before you do anything, remove the spark plug from the affected cylinder. Using a pen light, look through the spark plug hole. If you see a hole in the top of the piston, or a great deal of pitting, you can assume a rebuild is in order. If the piston crown appears ok, pull the head and start your investigation from there.
If the compression reading is ZERO, pull the head now. The items that would cause the result of zero compression are going to require the head pulled anyway.
Walley -- Your certainly right. -- But detecting a hole or piston crown damage may influence ones decision whether or not to spend any time or money on the power head. (Sort of like taking the engine cover off and seeing a rod or two sticking through the side of the block.) If a person isn't up to the task of rebuilding, why bother expending the engergy -- unless of course its curiosity. If that person has the time, skills, and desire to investigate further by all means go for it. "Money Saved is Money Earned".
You're right as well....I look at it as the guy that will be doing the repairs insted of the guy that may have it done at a shop or replace powerhead.<br />Either way is fine, I just thought as a learning experience, it would be a good place to start as there isn't much to go wrong with removing a head even if someone else does the work.
