headgasket install failed

[gaddis]

My headgasket blew after running my 50trim at 19 psi with less than 3 deg knock for a few weeks.

I bought ARP headstuds and the Mitsu 4layer headgasket and decided to change my 35K timing belts while I was at it. Once I had a look at my timing marks I realized that my intake cam was advanced one tooth which may have contributed to the original headgasket failure. I had my head decked by a machine shop which has done extensive work on 4g63 engines. I cleaned my block with brake parts cleaner and coated it with copper sealant. I also copper coated the head side of the gasket.

However I believe I fd up on torquing down the studs. I only applied the moly lube to the threads not the washers and nuts. Also I only torqued the nuts to 70 ft-lbs as directed by the ARP instruction So I believe I ended up wih a seriously undertorqued head.


Result massive oil and coolant leak out the overflow bottle.

Will retorquing the studs with proper lube seal it up or do I have to take the head off and clean everything and copper coat again?.
I really don't want to have to take the head off again as this is my only car and I've been renting a car the past week.

Could I just retorque the studs and do a compression test to see if the gasket is sealed correctly before I take the head off again?

 

[BoostinAWD]

70lbs ouch.

I torqued mine to 87lbs and have seen upwards of 23psi with no probs.
Yea try and retorque it.

 

[ARTSUPRA]

did you check if the head or the block were warped ?

 

[gaddis]

Yeah, the head was warped, so I had it decked. RRE, MachV, and my machinist who was a Mitsu mechanic for 15 years during the late 80's and 90's told me that I didn't need to resurface the block, just the head. Since I didn't properly lube the ARP studs and only torqued to 70 the gasket leak was huge. Pretty much 50/50 mixture of oil and water came out the overflow bottle. Since there is now oil/water around the head gasket do you think it will still seal even when I apply 90ft-lbs to the properly lubed ARP studs? I'm going to do a compression test before and after I retorque them. If the after #s are bad I guess I'll just have to pull the@#$@#$ head again.

 

[ARTSUPRA]

you can probably reuse the gasket tought

 

[DSMJim]

The lube eliminates some resistance when torquing them down, so 70ft/lbs dry is like 55ft/lbs or so with lube. Thats way loose, no wonder it went ca-ca... For the sake of taking the easy road the first time, try putting on some lube and torquing to 87ft/lbs (like boostinAWD said) and see what happens. You may seal it up and not have to worry about it if the head gasket is ok. If it doesn't work then you still have to pull it off, your no farther behind or ahead and at least you tried to make it work.

I wouldn't suggest trying to re-use the headgasket just incase though or you could be doing another re-re on the head if it's no good. It would probablly be ok, but you wanna chance it again? Another week of car rentals is more than the cost of a new HG...

 

[BUCK]

I only applied the moly lube to the threads not the washers and nuts. Also I only torqued the nuts to 70 ft-lbs as directed by the ARP instruction So I believe I ended up wih a seriously undertorqued head.

As long as some Moly got on the "bearing face" of the Nut where it bears against the Washer you were cool - You don't want the Nut "galling" on the washer.

Of course you can TRY & re-torque to 90 Ft-lb or so - but it won't work - you'll be jerking the Head - & Hell No ARTSUPRA you can't re-use the freaking Head Gasket!

 

[ARTSUPRA]

HKS and Greddy METAL head gaskets can be reused not sure about the Mitsu once.

 

[BUCK]

Originally posted by ARTSUPRA
HKS and Greddy METAL head gaskets can be reused not sure about the Mitsu once.

Well those would be the POS's that leak the FIRST time you install them anyway... so why NOT reuse them!

 

[ARTSUPRA]

They hardly ever leak if proper machining and lapping of the head and block are done.

Going by Supra experience, and I see no reason why'd they fail on DSM

 

[gaddis]

"As long as some Moly got on the "bearing face" of the Nut where it bears against the Washer you were cool"

This didn't happen.

"You don't want the Nut "galling" on the washer."

This did happen.

It's a metal heagasket. Aren't they supposed to be reusable? Anyway, I'm still going to try to take the washers and nuts off one at a time torque them to 50 which is probably equivalent to 70 w/out lube, and then retorque them all to 87-90. A compression test before and after ought to tell me if it's worth flushing the coolant and changing the oil and trying to run it again. Otherwise I'm going to have to do the whole thing over.

 

[gaddis]

Compression test before retorquing:

180, 185, 165, 175


WTF

Not what I expected.

Any thoughts???

 

[TTKarl]

Well, 165 looks slightly low. It is also possible that the oil gallery is leaking into the coolant gallery and the gasket area around the cyls is still ok. It is also possible that you have a completely differnt problem.

Here's what I would do if I were you. To a cyl. leakdown test and see if any cyl are leaking into the cooling system. You could also go to napa and get a block tester kit which tests for exhaust gases in the cooling system. Or option 3 pressure test the cooling system with the spark plugs removed and look and see if you see coolant entering any of the cyls.

Good luck

 

[gaddis]

Well I retorqued everything to 85 ft-lbs (some of the nuts could be untorqued with 50 ft-lbs ) Car idled for about 10 minutes before it started to overheat at which point I shut her down. Definitely improved though. I'm sure oil got in between the gasket which coked up and is preventing the gasket from sealing. I really hope the block isn't warped. I'm checking that this time. I talked to RRE and they said it's fine to reuse the Mitsu metal HG. Time to start tearing the damn thing apart again. Worst thing is I only got to play with the 50trim for 2 weeks before this crap. Engine sounds way smoother now that timing isn't a tooth off.