Could ARP2000 Head Studs fix my coolant leak?

When I got my car it was only boosting about 15PSI because the actuator was trashed. It had presumably been run this way for a year or so. Seller advertised that it had a "new head gasket". I fixed the actuator and got the boost up to where it should be, but then I got the dreaded coolant leak. It started very slow (as soon as I fixed the actuator), and over the last few months it has gotten worse and worse. Now filling the coolant ball to the max line only lasts me a few days.

So I've been dreading having to do a head gasket job, and I was shopping for some bolts/studs, and I saw this on KermaTDI's page for the ARP2000 1.9L TDI head stud kit:

"Are you losing engine coolant because of high boost pressures lifting the head? The stretch bolts specified by the factory are not up to the task of holding down the head under these conditions."

"If you have a "leaker' head gasket, these studs could very well "heal" it, without removing the head!! Simply remove each existing head bolt, one at a time, in the torque pattern specified in the factory manual, torquing each to 80 ft lb on the first pass, then 100 ft lb, and finally to 125 ft-lb for final torque. If you use the ARP-provided lube, there is no re-torque required!"

So now it has me thinking... my head gasket probably isn't BROKEN or physically damaged, my head bolts are probably just loosening, which would explain why the leak is getting worse. He probably installed the "new" head gasket when it was underboosting and therefore didn't experience coolant issues because it was "tight enough".

So... would it be possible that I could buy these head studs and, like it says, replace them without pulling everything apart, and everything turn out fine?

And if I try it, and it still leaks, are the new studs trashed since they've been torqued or could I still perform a full HG job and use them?

If it were mine, I would buy the ARP bolts and replace one at a time to see if that fixes it. If not, pull the head and have it, along with your block, checked for flatness and machined if necessary. Problem solved. Good thing about the ARP studs is they're re-usable!

Great. I was about to ask you if they were re-usable but it looks like you edited before I could get here!

Thanks!!

BTW, I'll apparently be switching from bolts to studs. Is that as simple as screwing in the stud and then screwing the nut onto the stud?

are you sure its not a water pump leak/radiator etc? no sign of dripping underneath at all when cold?

Where is it specifically loosing coolant from? Can you see pink crusties? Is it pressurizing coolant and forcing it out of the bottle?

OP: My car was doing the same thing and I had the Cosworth ARP head bolts installed pushing 28psi. By being light on the skinny pedal and driving I wasn't losing any coolant but the bottle did have some extra pressure in it after engine cool down.

I pulled my head off this past Saturday and noticed Cyl #1 piston was a little bit cleaner than the other 3, will let you know as to what they find. I guess the bad part about using shimmed headgaskets is after removal it is hard to verify where it was leaking...

bhodgkiss, oldpoopie: It's only leaking from the coolant reservoir. It overpressurizes and pushes the coolant out, and yes, I see the pink crusties.

It does not leak if I park it and open the coolant ball cap to release the pressure, then replace it.

At first it only did it when I ran it really hard, but now it leaks out during normal driving as well, and G12 is not cheap!

rocketeer: thanks for the link!

I've found that if its been leaking for a while, you'll need to re-gasket it at a minimum.

the longer it leaks the more the gasket gets damaged/eroded away. you may get lucky though. doesn't take long to try it. we did it on pierre's car and it fixed his leak but his only blew it out once before the stud install.

Yeah, hopefully I'm in luck. But ultimately, I'd want these ARP2000 head studs if I end up having to swap the head gasket anyway, and since they're re-usable, I'm not losing anything by trying it.