is my head shot or rings

[John DeCampli]

so i know a decent amount about cars and the new dsm i bought did not run when i first got it i rewired all the bare wires and then checked the timing, it was 10 teeth off so id go ahead and say the valves are bent but i set it in time and it will start. so i decided to compression test it and it was low and wouldn't hold compression in 2 cylinders but with a cap of oil added the compression increased a decent amount, also the oil smells like gas. so i am just trying to figure out if i need a head or a whole block. i am pulling the head as we speak.

 

[StarFawkes]

checked the timing, it was 10 teeth off

i decided to compression test it and it was low and wouldn't hold compression in 2 cylinders but with a cap of oil added the compression increased a decent amount, also the oil smells like gas

Definitely rings.

 

[slickers111]

Do a leak down test on the head if the valves arent noticeably bent. then look at the rings. If the rings arent sealing properly, drop a little oil around the piston and see if it leaks.

When my valves bent, is couuldnt build any pressure, so Id be leaning towards the rings also.

 

[John DeCampli]

the thing that's been bothering me is it seems to run okay when all i did was put it into time, i thought being over 10 teeth off the head would have to have bent valves like the compression is was building in the low cylinders instantly went away and did not hold the good cylinders held there numbers, also the car before i bought it off my friend, had a compression test done by myself about a week before it jumped timing and it had very good numbers in all the cylinders so id almost say the rings wouldn't be bad just weird to me how everything is acting

 

[Calan]

1). What do you mean by "timing was 10 teeth off"? If the timing belt jumped ten teeth, you either have valve/head damage, or a problem that is liable to cause valve/head damage at any time.

2). If you ever suspect valvetrain damage, do not do a compression test. The only thing cranking the motor over with valve damage will do is cause more damage. Do a leak-down test instead as slickers111 said.

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

 

[John DeCampli]

i mean that the belt jumped 10 teeth at the crank supposedly when the car died on my friend he wasn't beating on it but i know that many teeth it shouldn't have a chance, but when i would put the crank in time the cam marks would be up and down from each other rather then lined up 10 teeth, id do a leak down test but don't have access to one and have never taken a car to anyone to be fixed and not trying to now im betting on its the head but i was just trying to see what people would think and im not to sure how to check the valves when its off.

 

[Calan]

All you technically need for a leak-down test is an air compressor. You can rent a tester for free at most Auto Zone stores, or buy one new for $30 at Harbor Freight. Even without a tester, you can still inject air into the cylinders using a compression tester hose to find out if you have obvious air leaks and/or bent valves.

Regardless....if it jumped time that much, you need to find out why and fix it. That would include a complete timing job with new belt and possibly a new tensioner, pulleys, etc.

FWIW, if it truly jumped 10 teeth at the crank and continued running for more than a couple of revolutions with the t-belt still intact, you are most likely going to be pulling the head.

 

[John DeCampli]

okay i wasn't sure of how expensive they are but that is not to much how would you tell if the valves are bad or not from it though, i have read up on it some but still not to sure, and i was planning on pulling the head but i was just trying to see if i could find out if i need a whole block or just a head because i havent had alot of time lately to get the head off and because a friend just totaled his dsm with a brand new engine he just built in it and is now selling it but i don't have the money to be buying a motor i don't need

also i know it jumped timing because the belt was soaked in oil from a cracked valve cover and the tension er did not seem to be as strong as others that i have removed while doing timing belts on these cars

 

[Calan]

how would you tell if the valves are bad or not from it though

Trust me.... if the valves are bent (especially the intakes), you'll know. Turn the motor CW by hand to where all intake valves should be completely closed and hold it there with a wrench, break-over bar, etc.... and then inject about 50psi into each cylinder. You'll hear air rushing out of the intake piping, and you can open and close the throttle blade and hear it changing. In fact, even valves that aren't bent but just not seating properly can be found this way.

i have read up on it some but still not to sure

Read some more.

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

the belt was soaked in oil...

Any t-belt that has been exposed to more than a splash or two of oil is a ticking time bomb. That belt will need to be replaced, and it is well worth the few extra $$$ to replace the other timing components and water pump while you are at it, especially if they are factory original or unknown.

For me personally... if I'm gonna fight with that damn front cover while the engine is in the car, I'm replacing everything behind it that I can afford to.

 

[John DeCampli]

Okay thank you for the info I'll deffinitly check it for a leak down tomorrow and read up on it more , I'll let you know what I find out. And I'm deffinitly not going to put used parts on with a new head I have done plenty of rempairs before just never had a car Jump time because I usually replace the belts right away if needed and this thing was absolutely soaked in oil the whole hood and engine bay was soaked even , but thanks for the feedback and the much needed info