i would like to test my maximas engine compression... i already have the gauge for it but i need to know how to use it!

does anyone know how? if so, please explain..

or

does anyone have any links? like that online chiltons guide (that i cannot find anymore)

thanks

 

Anybody??????

 

Take out a spark plug putt the thing in there and crank the engine its kinda two person opperation. Dont quote me on this though

 

unplug ingnition coils, take out fuse for fuel pump take out the spark plugs, inserts guage crank the engine 4 times .... this will be your final reading. repeat to all other cylinders. this is a dry test. for a wet test before you put on the guage squirt some oil in the cylinder and you will ahve a complete sealed cylinder.

 

Yeah if you have the low compresion on the dry test, do the wet test which will tell you if it's your piston rings (you will get good compression) or something in the head. But if after doing a dry test you discover that you got a low compresion I would just get a used maxima motor (much cheaper then rebuild), unless you are planning on building it.

 

thanks for the replys...

so you need to remove all spark plugs at once, or one at a time?

then crank the engine 4 times and the final time is your reading right?

i've heard something about blocking the air intake or throttle body - is there any truth to this?

and my last question, when replacing the spark plugs do i need to torque them to a certain specification (17lb)?

 

If you plug the TB, then your compression would be 0 right? Since it cant suck air, it would be a vacuum and when the piston moves up, its just releasing the vacuum, right?

 

You should go out and buy yourself a haynes manual ($15 Autozone)
it's the best investment in bridging the gap between you and your maxima.
i learned how to do all my mods from it and of course the .org

It outlines the complete steps for a compression test as well as other very useful info. i.e. torque specifications for most engine bolts and tightening sequences.

-Vadim

 

make sure the engine is at operating temp and throttle is wide open , otherwise results won"t be accurate

Nick.

 

Why do you want to do this test? Are you noticing drastic drops on your engine's performance? Wouldn't that send an obvious sign prompting for a compression check providing that you've checked out everything else leading up to that? Otherwise, why go thru the hassles of testing? Another reason I could think of why one would want to do a compression test is if one is contemplating on supercharging.