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2003 Suzuki ltz 400 compression problem/will not start

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One easy test would be to use compressed air to find the leak. 30 psi is way too low. Drop the piston to BDC and use your compression tester fitting to pressurise the combustion chamber with an air hose. Look for the leak. The rings will blow buy but if it's a valve seat issue you will hear it thru the carb or exhaust. If the jug or head is cracked the cooling system will start to bubble out coolant. ( remove the oil filler cap and radiator cap before doing this) If it's air cooled, forget the radiator portion.

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well my wall is fine. and i set the timing a few times and i just got new valves. and sorry for putting up so many postes

Don't get me wrong, please feel free to post as much as you want, just don't start a whole new thread when you already have one going on the subject. If you have any questions, or want a suggestion on anything that relates to your problem here, post 100 times if you want. I don't want you to think there is such a thing as posting too much, if you have a question or something to say, feel free to post it.

When you say the wall is fine, do you mean that it appears fine? or did you have the cylinder measured with a micrometer to see if it is worn. You got new valves, but did you get a valve grind? New valves in an old head with worn valve seats may not seal too well. Did you check the valve adjustment? Replacing old valves with new will most likely change the valve clearance, if they are too tight, they won't close all the way and compression will leak by. Id say that the most likely cause is that the cylinder has become too large for a standard piston or your valves aren't closing because they aren't adjusted properly.

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