Head Gasket Woes, Suggestions?

[ItzGenX]

Ok, lets start by pointing out that my motor is a SR20DET 90mm bored JWT sleeves with CP pistons. The block was recently surfaced along with the head. JGY had no clue as to what they were doing and looked like they milled the block with a dremel. So after going through a couple of custom cometic 90mm head gaskets before finding there was more to the problem. JGY wasn't smart enough to check clearances of piston to bore before assembling them into the motor. The pistons were 1mm too small (wow!). So I corrected all the problems myself by ordering CP 90mm pistons and a couple cometic head gaskets (.040" 90mm). While I waited, I sent the block off to the machine shop here locally which has done great work for my friends. The head was milled, so was the block. It looked way better then the JGY dremel job when I got it back. When the pistons came in, they also made sure the bore was up to spec for the pistons (they were down to the 'T').

Anyway, after I got everything together and the motor running again, the head gasket gives up again! Water gets into the oil very slowly but surely. My question is, since I KNOW my head and block are flat (almost mirror finished), how would I go about making a MLS gasket seal better? My theory is that it is leaking from between the cylinders where the water jacket slits are. Plus being 90mm I have 4mm less clearance between cylinders to seal. Is there anything I can do to a new gasket before throwing it on to help seal this puppy up? I was thinking copper spray, but I do not know much about this stuff or anyone who has used it before. Enough of my ranting, time for ideas. All replies are much appreciated.

[240SXer]

Are you running upgraded studs? How tight are you going? I've heard 60+ for ARP studs.

[180fan]

You should be using ARP's head studs. Tighten to 70ft-lbs. You can do 80 if you want but I felt no need to do that with Greddy's headgasket which alot of people seem to have leaks with. Do you know which area seems to be at fault? Most problems like that I've seen have been between cylinders 3 and 4. You can also try using a sealant.

[Silvia007]

I either use Copper spray or red silicone that I spread around the coolant holes (saw this from an SR build up in a magazine). Works great. Also, at this point in your project, ARP is a must.

[ItzGenX]

Yeah, there are plenty more upgrades I did not list as they don't pertain to the problem. I will try copper spray on the gasket along with sealing off coolant passages with RTV. I do indeed have ARP everything. Head is torqued down to 80ft/lb in 5lb increments.

[yellow_jacket]

Are you absolutely sure its the head gasket? Did you do a leak down and compression test? Did the machine shop check the block and head for cracks?

I would be tempted to pull the front cover and make sure that the coolant passages there are not leaking.

[ItzGenX]

I found the problem. Also, neither the head or block are cracked, had that checked when it was there at the machine shop too. Water is indeed entering through the cylinder via head gasket. Don't get me wrong the head gasket is doing it's job, there is just this other problem. Here is my post from FA that I have posted.

"The head and block was verified flat when I got it back from the machine shop via straight edge. It still is flat, as I've removed the head yet again today. I've now run into a new problem that means I want a new block. I do not want this block anymore, it is my new door stopper. The new problem I've found seems to be one of the problems I thought was fixed. When JGY gave me this motor (fully assembled), the sleeves seemed a bit pushed down below deck a little when I finally tore it down due to the same problems. After machining and such, I had it flat as can be with the rest of the block face. Well now, it seems all sank down again except #3. I've measured and 1+2 sank about 0.3mm. #4 sank 0.9mm (wierd it sealed the best by looking at the pistons, 1+2 were shiny as hell, 3 was muddy black, 4 was fine charcoal black with no moisture). Unless there is anything that can fix this sinking sleeve problem, I will use this block as a JGY showcase and move on to another block. I may be searching for a short block soon. I also have some CP 90mm pistons and 89mm pistons as paperweights. What a week."

[nismostate]

I've noticed that JGY has been screwing a whole lot of people over. sorry about the problem. just go with a new block.

[need2drift]

Damn man that sucks dude I just sold a spare block and head that I had for a while... I would have hooked you up

[ItzGenX]

Yeah, well now I think I am going to go with another block, just need to look for one. I think I am going to go 86.5 on stock sleeves. Looks like I am going to have another set of pistons to play with . I might take a day off work one of these days on the weekend and make a drive out to one of these sr20 vendors in FL. It is only 6hrs away I think to Jax. I can probably have a choice to pick out which SR I want to reduce problems and shipping.

[need2drift]

Yea it would be alot cheaper if you could find one close by shippin is too damn much!!!!!A trip to florida isnt a bad idea at all man, that really suck though I just shipped that block to orlando like a week ago and it was in great shape

[HybridOne]

i have a block that a piston melted in...since you will be boring it over...it shouldn't matter. There is scaring from where the piston scraped the wall, but it isn't that deep. Lemmie know if you want a pic or something.