possible blown head gasket

[amctmg]

yesterday I was doing some full throttle runs and doing some adjustments with dsmlink and I heard a popping sound like a backfire and now I have no compression in 1 and 2 cyl's. I checked all the timing marks line up so the timing belt didn't jump. The car does run and there is no oil in the coolant or coolant in the oil so what I am thinking is the head gasket must have blown between the 2 cylinders and no other damage has occured. Would that be a safe asumption?

 

[hopwoodp]

A better way to figure this one out is to do a leak down test. Vfaq.com has information about this. Either way it doesn't sound too good. Unless you were running really lean. Did you get
high knock readings? Better yet, do you happen to have a log of the run?

 

[amctmg]

the vfaq link is broken, what is a leak down test and how is it performed?
I did not log run. I was doing a boost leak test the other day and I adjusted my boost controller all the way up and I forgot to lower it before driving and I did a bunch of full throttle runs without paying any attention the the boost gauge which was being pegged at 30 with a 14b, stock IC and 550's.
apparently this is what caused the damage. I guess I'll just have to tear the head off and see what is what. Hopefully its just a head gasket

 

[forcefed 95]

Here you go heres the link for you, just go to where it says engine on top and click, and then go to where it show leakdown test and click the link. hope this helps out let us know
http://vfaq.com/index-main.html

 

[amctmg]

the link for the leakdown test is broken is what I meant

 

[forcefed 95]

Oh sorry did not know that. Well here try this instead
http://www.dsmtuners.com/forums/showthread.php?t=97401

 

[Nors]

http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm


There ya go. If you can do a compression test, you are capable of a leakdown. As long as you got the right stuff.

 

[amctmg]

ok I googled it and from what I read and the rig job I did I have found that it is definately the head gasket due to air coming out of cyl 2 spark plug hole while I pressurize #1.

I'll tear it apart and maybe take a pic of it but it will be a few days I'm sure.

thanks guys

 

[nates6969]

When you get the head off, really make sure the cylinder walls and head are clean and free of any possible cracks. If you have 0 Compression Im wondering if you may have further problems. My buddy hit 20 and was way too lean, detonated, and melted a piston. Once you swap in the new head gasket, bolt it down and do another leak down before doing all the timing and what not

 

[amctmg]

finally got the head off and found as suspected a missing piece of head gasket between cyl 1 and 2. However, there also happens to be a groove 1/4 inch by 1/8 inch burned through the head where the gasket was missing. anyone know if it is weldable?

I have a spare head but it has bent valves so I could transfer these valves to that head but then I would have to buy an exspensive tool. whereas, I could get the bad head welded for free at work.

suggestions and comments welcome