ok so i went to get my car tuned the other day after a rebuild head install. we used arp studs and a brand new oem headgasket...

first rip in the dyno it sounded awesome all the way until 7k...

at 7k oil started gushing outta my oil dipstick

we did a compression test... and in cylinder 2 im reading only 120... all other cylinders i have 150

the tuner claims its a blown headgasket or improper installation of the studs/headgasket

any imput fellas?

 

Not always..... Do you have the PCV from the valve cover vented or does it feed back into the intake like it is supposed to?

Did you check oil for coolant or coolant for oil?

I would have someone else check compression again. Sometimes its hard to get EVOs to evenly read yet they are in tip top condition.

 

I was the one who ran it on the dyno. During the pull, I was monitoring AFR and boost, both of which remained perfectly flat. The power curve, which I did not have displayed during the run, peaked at 200hp, then almost immediately dropped to 90hp and remained in the low 100's all the way through. I stopped the run as soon as I saw the oil splatter all over the windshield and the wall of my dyno cell. My first thought was PCV as well, which I told them to check before anything else. I did check compression, and cylinder #2 was 20% lower than the other 3. Idle was also rough and vacuum was @ -4 on his autometer gauge when it had been about -9 just before the run. After looking at the dyno graphs, I'm leaning more to an improperly installed headgasket.

 

Sounds like the HG. Who installed the HG? Was the head milled?

 

^^^ yes sir... head was milled.. and my friends and i installed it... we both know a bit about cars... and yes we use OEM specifications with the install and also a torque wrench...

 

do a leakdown test, that will tell you exacty what is happening.

somehow your crankcase is being pressurized. it does sound like a HG to me, maybe you got a defective HG

what were the torque specs that you used on the headstuds? did you use moly lube or motor oil when torquing them down?

 

any update?

 

When they pulled the head and checked, they found a channel of corrosion that led from cyl 2 to an oil port. Combustion pressure was leaking by and pressurizing the crankcase because of this. I recommended having the deck surfaced prior to reinstalling the head yet again, but I doubt my advise was taken.

 

Yes nick did not have the head checked nor did he have the block decked either. we need clean the deck as best we could and reintsalled the head. using the 40 , 60 , 85 method. 85 since we are out of arp lube so used motor oil. we got hung up when nick snapped a cam bolt off in the head so now he;s got to order a whole new set of them. He tried using the end caps to pull the cams down against the valve springs instead of doing it evenly and snapped the cam bolt off. lucky once again we got it out. This build is doomed lol.

 

apon the 2nd head install.... FINISHED.... still may be a few bugs tho.

torqued and retorqued after letting the engine warm and then cool down over night...

did a compression test the next morning ...... registering 175/175/175/175

after taking the car for a spin around the block at 1 am..... I blew antifreeze all over the windshield at the top of third gear....
I end up barely making it back to the garage and me and evan started to asses the problem....

now my first thoughts are ooooo friggen great... i blew it again

come to find out the antifreeze line to the turbo popped off and blew all over the place.... now i HOPE this is the only problem... as my dipstick actually stayed in and i didnt blow any oil anywhere.... oil level is fine...

but apon another compression test just to make sure everything was ok ..... registered 155/165/160/155

is this a compression problem or blown head gasket yet agian??

 

do a leakdown test and stop trying to cut corners

hopefully you just forgot to tighten the clamp on the turbo coolant hose and it just popped off

 

nick ur compression is good. anything above 150 is good. big we forgot a clamp on the turbo coolant line. Everything should be good to go.

 

Just curious but what was the original reason for doing a head gasket on the car...and on the dyno was the car over heating? or was the coolant full? You may have had an air pocket.

I would do a leak down on the motor reguardless just to make everything is perfect.

If you want one down i can do it for you...PM me

 

i did the headgasket because i put a built head on.... and i just took it for a spin ... all the way to 8k with no problems... no oil anywhere... dipstick stayed in this time!! lol

 

You could get away with the stock head going to 8k no problem. I used to rev out my stock head with just cams/arp headstuds to 8100 in 4th.