replace head gasket when installing ARP?

[54321chris]

I'm planning on installing ARP head studs on my 1.6td while I have my car out of commission, and I am wondering if I need to replace the head gasket when doing this.  I put a 1.9 metal hg on it just a few months ago.  I'm not planning on pulling the head.

[dennis]

I would.

[Vanagoner]

I didn't.  I had a HG leak.  I de-torqued the stretch bolts gradually, kept some snug tension on them once loosened, then replaced them one at a time in the sequence with ARP's.  Brought it back up gradually, no more leak.

[54321chris]

Thanks guys.  Anyone else with opinion or experience?

[Vincent Waldon]

Headgaskets are considered single-use by VW and I'd agree, since they squish a bit as they are torqued.  For 40 bucks I always replace 'em... cheap insurance and one less thing to worry about when you are roaring down the highway.

[Op-Ivy]

Headgaskets are considered single-use by VW and I'd agree, since they squish a bit as they are torqued.  For 40 bucks I always replace 'em... cheap insurance and one less thing to worry about when you are roaring down the highway.

Agreed. It's good preventative maintenance while you are already in there.

[8v-of-fury]

I heard of leaving them all torqued and completely de-torquing one at a time and replacing..

Safe or not?

[Vanagoner]

I can't speak for anyone else, just for what I did and what worked for me.
I de-torqued the stretch bolts as gradually as I could in the standard pattern, but kept the final tension to 20 ft-lbs.  I replaced them one at a time with the head being unmoved and under 20 ft-lbs tension from either the bolts or the studs, until I got all of the studs installed.  I brought them up 10 lbs at a time till I hit 80 (with the molly grease).  I ran it with coolant cap off until up to operating temp. Let it cool and re- torqued one last time to 90 and left it there.  Works fine for me.  YMMV.