Blown Head Gasket

[tsunari]

Did some headwork about 24k miles ago (Engine now has 156k on it) . . . 3-angle valve job, new belts, mits. head gasket, etc . . .

Just did a compression test & leak down test and got the following:

1, 2, 3, 4 [Cylinder]

140, 180, 180, 180 [psi Compression]

60, 6, 9, 5 [% leakage]

From the sound of it, I have a blown head gasket between cylinder 1 & 2 (sounds like air is coming out #2 spark plug hole). Questions are:

1) What would've caused the head gasket to blow with only 24k miles on it?
2) What should I replace when I get everything apart? (Arp head bolts, aftermarket head gasket, PT Cruiser HLAs, etc. . . )

Any and all SANE suggestions/ideas are greatly appreciated.

 

[unlikely hero]

ARP head studs are 14mm or 9/16 same thing but it has to be a 12POINT socket.
So is the composite headgasket that bad??? Reason being is that I just ordered one. I thought it is fairly decent. Another question is copper spray on the intake gasket? Its a paper gasket. Will the copper spray help?

=Jason-

 

[1990CherryTSI]

run your fingers up and down them around those weird spots. Feel anything? Any type of change in wall? If not, I'd say it's nothing to be concerned with. I pulled my motor apart, pistons had broken rings but the walls still have the perfect hatch marks on them so i'm going to hone, new pistons & rods, arp, 4 layer and go with it. As for the intake/exhaust gaskets? Look at them, if they're worn then replace them so no leaks occur. Looks like you found the route of your problem, at least it should only cost you around $175-200 to fix, plus the extra stuff you're throw'n in. Did you not have the valves checked when it was apart last time?

 

[jer28]

I don't wanna hijack the thread here but i'm in the same boat as well. I'll be bringing in the entire head to the machine shop and letting them have at it. Theres too much that I could screw up! As far as the block is concerned I can probally handle that much of it. Have you done any cylinder walls before? I have the attachment for a drill and I think you use a medium speed and keep moving it up and down to achieve the cross hatch pattern?
Also before you put in the rings maybe someone could tell us the best way to stagger them (you probally already know but I have no idea). I usually stick to 90 degrees apart, they will probally move once the engine runs anyways. Good luck with your project, looks like we've got a few hours ahead of us....

 

[BUCK]

My 2 cents worth...

1. - Note the Oil Stains on the Head Gasket around the "wet" cylinder.

http://www2.msstate.edu/~msa8/PiX/DCP_3293.JPG

I think the Head gasket was improperly Torqued the last time it was installed OR indeed the Felpro gasket is just crap as everyone says it is. IMO one of those 2 is the reason for this failure. Use the Mitsu Multi - Layer with new fasteners being it's a 2G.

2. - As far as the Head I would at a minimum put new Valve Guide Seals in & clean hell out of it.

3. - I would certainly consider replacing the Piston Rings as they are caked in carbon like a BBQ grill at the moment. Might as well do Rod Bearings too - & BTW - You could check your Thrust bearings while you are down there too...

4. - If you re-Ring the Pistons you might as well disable the Front Balance Shaft, & Remove the Rear Shaft while you are in there.

5. - Replace all Front case Oil Seals & Water Pump while doing the above.

 

[tsunari]

>>So is the composite headgasket that bad???

My friends and I believe the Mitsu composite was not torqued down properly when it was put together last. I had just put everything together and torqued it down. I never re-torqued the bolts after the engine had been run for a while . . .

>> Did you not have the valves checked when it was apart last time?

Actually, reason I had it apart the 1st was was because of a burned valve. Had a 3-angle valve job done, mild porting, and new valve guide seals put in.

>>Head gasket was improperly Torqued the last time it was installed OR indeed the Felpro gasket is just crap as everyone says it is

I agree . . . I neglected to re-torque the head bolts after letting the engine get up to operating temp and let everything expand. This time I have ARP head studs. I've done some research and looks like most ppl are torquing to 80lbs with the ARP lube. Is that correct?

>>As far as the Head I would at a minimum put new Valve Guide Seals

I'm thinking that if I get all of that carbon in the combusiton chamber cleaned up, the valves will seat properly once again. Would I still need to change out the valve guide seals even though there are only roughly 30k miles on em? Or is it a 'while it's off . . . ' type of thing? As well as titanium retainers, etc . . .

>> disable the Front Balance Shaft, & Remove the Rear Shaft while you are in there

Plan on doing that today or possibly tomorrow- just depends on if the weather wants to cooperate. :thumbs:

>>Replace all Front case Oil Seals & Water Pump
Gonna do this one too

>>I would certainly consider replacing the Piston Rings & Rod Bearings
Any idea how much that would run? I haven't done much research in that area . . .

 

[BUCK]

>>I would certainly consider replacing the Piston Rings & Rod Bearings

My concern is that even though your Compression numbers were'nt that bad IMO from what I see in the Bores & Head I think the Rings are completey "coked up". If you don't re-Ring it at least flush the HELL out of each bore with kerosene till it runs clean out of the Oil pan.

Rings about $150 a set (all 4) from Mitsu.

Rod Bearings about $112 a set (all 4) from Mitsu.

The valve Seals should be OK with only 30K on them.

Excellent move on the BSE, I personally think can help avoid CW.

Check out your EGR of course - it can make this kinda mess too.

 

[tsunari]

Originally posted by BUCK

Check out your EGR of course - it can make this kinda mess too.

Hey . . . I actually spent about an hour last night researching this . . . pros / cons of blocking it off etc . . . Right now I'm not sure if I should just clean it up and put it back on, or just block it off and forget it.

As for Rings & Bearings, sounds like I'm just a few hundred $$ away from a complete rebuild. If I decide to go that route, should I just go ahead and get 1G rods and ARP bolts?

 

[BUCK]

1G Rods - about $117 a piece - PLUS the macine work for your 2G Pistons - getting expensive here really QUICK... & the Compression numbers were pretty damn good actually... I'm leaning toward $10 worth of KEROSENE...

If you elect to keep the EGR - Just make sure the damn thing is sealing, personally - I tapped the hole in the Head while I had the Intake off & threw a brass Pipe Plug in the little Exhaust Port that mates with the Intake tract for the EGR.

 

[tsunari]

Originally posted by BUCK
1G Rods - about $117 a piece - PLUS the macine work for your 2G Pistons - getting expensive here really QUICK... & the Compression numbers were pretty damn good actually... I'm leaning toward $10 worth of KEROSENE...

If you elect to keep the EGR - Just make sure the damn thing is sealing, personally - I tapped the hole in the Head while I had the Intake off & threw a brass Pipe Plug in the little Exhaust Port that mates with the Intake tract for the EGR.

I've never done the kerosene trick . . . How would I go about doing it? Would a few cans of MCCC do the same thing?

 

[BUCK]

How would I go about doing it? Would a few cans of MCCC do the same thing?

That may even be better.

 

[tsunari]

Originally posted by unlikely hero
ARP head studs are 14mm or 9/16 same thing but it has to be a 12POINT socket.
So is the composite headgasket that bad??? Reason being is that I just ordered one. I thought it is fairly decent. Another question is copper spray on the intake gasket? Its a paper gasket. Will the copper spray help?

=Jason-

Both my intake manifold and exhaust mani gaskets are made of metal . . .

As for the studs . . . I know the bolts are 14mm, but what size tap do i need to clean the threads out on my block? is it an 11mm x 1.5 tap?