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help compression at 60

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miller97tsi

15+ Year Contributor
221
1
Jan 5, 2008
jacksonville, Florida
read a few posts didnt really help out that much as far as my concern. i believe my timing is dead on. the cams move and rotate so i believe the valve train maybe ok. my compression is 60 psi. what else can it possibly be.
 
There are 3 basic areas where air can escape: the valves, headgasket and past the rings. Just because your cams rotate doesn't really tell you much, it could be any of those three. What is the compression on the other cylinders? If I were to take a blind guess, I would say that you cracked a ringland. Friend did that and he had 70 psi on that cylinder. Regardless, if you performed the test correctly and 60 psi is true, you are going to need to tear down the motor and figure out what is wrong, as I wouldn't suggest driving it until you figure out what is (for the risk of further damage). What are the symptoms that prompted you to do the compression test in the first place?
 
i installed the cams it wont start so i started with the basic things to check and i cant seem to figure out why it wouldnt start. i got fuel and spark just no detonation. so the compression check was the next step for me. and it was 60 across the board.
 
I have that same problem also. mine is at 90 psi on all 4. i was wondering what would need to be done to fix it. and how long it would take.
 
All of them...wow. Are you absolutely sure your cam timing is right? If the car ran perfectly before the cam install, then it definitely has something to do with that. If you installed the cams out of time, it is possible that the pistons bent the valves, although I guess then compression wouldn't be so uniform. What cams?

I have that same problem also. mine is at 90 psi on all 4. i was wondering what would need to be done to fix it. and how long it would take.

If the top end is fine, cam timing correct, no problem with the springs, rockers, lifters, etc., you probably need to tear it down. Bent valves (or valves with holes) and headgaskets need the head taken off. Replacing the rings and possibly the piston necessitates a rebuild, or at the very least pulling the head and oil pan off.
 
they were comp cams 101-100 it ran a few weeks ago with the cams now it just wont start and it was 60 in all cylinders. and suggestions bent valves possibly
 
before this happened it ran but it started to make a clicking noise then dumped oil like crazy ( 3 out of 4 quarts in a half mile) oil was all over my engine compartment. I stopped driving it and had it towed. have not driven it since but really want to. any help would be great
thank you
 
they were comp cams 101-100 it ran a few weeks ago with the cams now it just wont start and it was 60 in all cylinders. and suggestions bent valves possibly

Ok man, you aren't making this very easy. You need to give as much info as you can in your posts, or we are all just shooting in the dark. So, you installed the cams, drove the car for a while, it ran great, then one day you go out and it won't start? Then you did a compression test, and it was 60 psi across the board?

Please, take some time to write your posts. Every post is like one run on sentence and it's impossible to read. If you want help you're going to need to give more info and write neater.

before this happened it ran but it started to make a clicking noise then dumped oil like crazy ( 3 out of 4 quarts in a half mile) oil was all over my engine compartment. I stopped driving it and had it towed. have not driven it since but really want to. any help would be great
thank you

First thing you should do is figure out where all that oil came from, I imagine it won't be very hard.
 
ok a few weeks ago i was running on stock cams car ran outstanding no problems. then i installed the cams wouldnt start. come to find out the cas was broke fixed it. then the car started fine idled between 800-1000 rpm sounded fine. after the warm up i turned it off and let it sit. didnt touch it for a couple of days thinking it was ok. then a few days ago i tried to restart it nothing. checked and double checked everything under the hood that i could possibly check. i have fuel and spark. timing marks seem to me to be dead on. then i decided to do a comp test got 60 in all cylinders. should i put the stock cams back in or you think that my valves are done? i have beat my head against the wall on this one for a few weeks now.
 
ok a few weeks ago i was running on stock cams car ran outstanding no problems. then i installed the cams wouldnt start. come to find out the cas was broke fixed it. then the car started fine idled between 800-1000 rpm sounded fine. after the warm up i turned it off and let it sit. didnt touch it for a couple of days thinking it was ok. then a few days ago i tried to restart it nothing. checked and double checked everything under the hood that i could possibly check. i have fuel and spark. timing marks seem to me to be dead on. then i decided to do a comp test got 60 in all cylinders. should i put the stock cams back in or you think that my valves are done? i have beat my head against the wall on this one for a few weeks now.

The stock cams shouldn't make a difference. Do a cylinder leak test or take off the head.

How did you do the compression test exactly?

If you did it correctly and have 60psi across the board then most likely you had to have done some damage.

Another thign is when you put in the cams did you start it right after putting them in? If so did you bleed down the lifters when you were installing the new cams?
 
Did you remove all of the spark plugs and hold the throttle open when doing the test? How did the needle move? Did it jump up on the first stroke or did it gradually build ? that can tell you alot too. You need to do a leakdown test. 60 across the board is strange to me.
 
when i did it i didnt hold the gas to the floor. i took al plugs out installed the checker and started. it pumped three times and held at 60-63 psi. first pump was at 15 second was at 30 and third was at 60. is there another way of doing this. also i didnt bleed the lifters down if i didnt what would that have done. what kind of damage are we talking about.
 
Another thign is when you put in the cams did you start it right after putting them in? If so did you bleed down the lifters when you were installing the new cams?

Theres your problem, your valves bent on start-up, whether they were timed or not, im sure your lifters are probably rock hard right now causing your valves to bend.

Only thing you can do to tell, is do a wet compression test with oil, if theres no difference, its your valves or timing. If your timings right, your valves are done.

Theres a lifter bleeding tutorial online, I bled mine with a paperclip.
 
ok let me check a few more things i hope thats the case i will post when i figure the problem out
 
is there a way of checking to see if i have bad lifters or would i just be shooting from the hip just looking at them? if my car was running fine would this really have caused my car not to fire? without taking the head is there a way to check for bent valves? i hope this is the problem thanks.
 
Again.... Do a cylinder leak test and see what you come up with.
 
i turned it off and let it sit. didnt touch it for a couple of days thinking it was ok. then a few days ago i tried to restart it nothing. checked and double checked everything under the hood that i could possibly check. i have fuel and spark. timing marks seem to me to be dead on. then i decided to do a comp test got 60 in all cylinders

Surpised no one mentioned this but if the car won't fire, then it wasn't warmed up when you did the compression test. And in that case, the readings probably won't mean much depending on the ring and bore tolerances your motor was built to. (But it should still be higher than 60...)

But it does sound like bent valves. As mentioned, do a proper leak down test, and you should find air leaking into the intake and or exhaust.
 
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