HELP ASAP, Just finished head gasket swap, did compression test,

[BlueOvalStangGT]

Hey guys I just finished swapping my head gaskets(thanks for the help BTW) and I did a compression test in the number 7 and 8 cylinders. I got 120 in #8 and 130 in #7. Is something still wrong? Its better then before but still not as good as my other cylinders. What could be wrong?

 

[RIO5.0]

That test is supposed to be done with a warm motor...cold, you may not get the seal you need for an accurate reading??

what are the other readings?? w/in 10% of those 2 cyls???

are the valves set-up??? hanging open a tad could skew the numbers???

did you test 7/8 before teardown and they were lower than the others???

bad rings in those cylinders if still low after the install???

 

[1105]

what he said...

 

[BlueOvalStangGT]

OK, before, I dont remember but passenger side was between 135-142 and #8 was 100. #7 was 110 and 5&6 were 125. Now here are the new results

4--142 8--120
3--142 7--130
2--140 6--120
1--140 5--130

 

[AznStanger3v]

are you cranking each cylinder the same amount of times?

 

[BlueOvalStangGT]

No I am not, I just crank it until it stops climbing

 

[DARK-5.0]

what he said...

Comments like this explain to me how your post count is so high. Haha, I'm just playin around Zach. But your right, what he said.

Jeremy

 

[1105]

Comments like this explain to me how your post count is so high. Haha, I'm just playin around Zach. But your right, what he said.

Jeremy

Comments like this explain to me how YOUR post count it to high too haha not really

He sent me an IM asking me what I thought, so I answered cause he was outside with his car.

 

[RacerRick]

did you check the head surface and block deck with a straight edge to see if its flat? head could by warped some. since its back together run it a while,heat cycle a few times(hot then cold) then re-torque the head and retest the compresion. good luck!

 

[Joes95GT]

OK, before, I dont remember but passenger side was between 135-142 and #8 was 100. #7 was 110 and 5&6 were 125. Now here are the new results

4--142 8--120
3--142 7--130
2--140 6--120
1--140 5--130

It's fine.

Joe

 

[BlueOvalStangGT]

OK NEW PROBLEM! Put all the plugs back in and tryed to start it. It cranks over but makes a funny noise. Its hard to explain but its like a 55gallon drum when you knock on it. It was pretty loud the last time I tried it before I turned it off. Any ideas?

 

[Joes95GT]

OK NEW PROBLEM! Put all the plugs back in and tryed to start it. It cranks over but makes a funny noise. Its hard to explain but its like a 55gallon drum when you knock on it. It was pretty loud the last time I tried it before I turned it off. Any ideas?

I'm assuming it's coming from the engine? Will the car start and you aren't letting it, or it won't start and makes that noise?

I'd have someone go under the hood (assuming it's from the engine) and try to see exactly where it's coming from. Once you hear where it's coming from, the problem can (probably) be fixed quite easily.

Joe

 

[BlueOvalStangGT]

It wont start and everyone is sleeping around here. Its a really weird kinda "hollow" sound.

 

[1105]

this one has me stumped... I've never heard that kind of noise from any car ever.

 

[BlueOvalStangGT]

Ok tried again, kept doing it and kept making that sound. Then my mommy came out cause i woke her up so i made her try, and it did it one more time and no it doesnt do it anymore. I only heard it once but I think it may have came from where my airfilter is

 

[wytstang]

Maybe you have a valve handing open. That would be the only way your air filter or general area would make a sound like that. The air is escaping your cylinders and being forced back up to your intake and out the air inlet. I hope I am dead wrong on that and I seriously doubt that is the problem. Check your spark plugs and make sure they or one of them is not loose.

 

[mo_dingo]

Ok tried again, kept doing it and kept making that sound. Then my mommy came out cause i woke her up so i made her try, and it did it one more time and no it doesnt do it anymore. I only heard it once but I think it may have came from where my airfilter is

You need to go back and check everything again. Start with the MAF, and go from there. Make sure every injector is in the right spot & make sure every vacuum line is attached. Then, if you still can't start the motor, recheck the rockers & make sure they aren't smacking the valve covers. Also, verify that the cam timing is correct.

Scott

 

[DARK-5.0]

Funny you should have sound like that. I tried starting my car the other night with the dizzy 180 out and of course ir wouldn't start, but i noticed a soft drum noise too. You might as well check that too.

Jeremy

 

[DARK-5.0]

Comments like this explain to me how YOUR post count it to high too haha not really

He sent me an IM asking me what I thought, so I answered cause he was outside with his car.

Hey, just because I don't post in all the thread I read doesn't mean I need to be ridculed as I was. HAHA, just playing. Its all in good fun.

Jeremy

 

[BlueOvalStangGT]

TTT for me! Heres a sound clip

http://s2.yousendit.com/d.aspx?id=A2B890E375DBFBBFE86FF61B45D03561