Actually for a 3.4... but they're the same right? Been having cooling problems with my 91 Trooper w/3.4. Decided to check compression. Front right cylinder 100 pounds short of the other 5... check head bolts, 3 from left facing head spins like a top. Broken off 1/8 in down into the block. Grr. So, working on removing the stub with various drills and Dremel tools, but can't quite determine what the metric thread size is. I think it's a 12 x 1.75, but I can't be sure. Plus, I don't even know what those numbers mean! LOL!

But, if any NW Trooper have a short or long block for the 3.4, I'm listening! And while this is down, I'm walking...

Thanks,
Jim Sorenson
Seattle, WA

You can go to any NAPA store and tell them you want a head bolt for a Chevy 2.8 or 3.4 or even 3.1.

Jim,

Already have the head bolts. I'd been planning on the eventuality of replacing head gaskets so there's a new set just sitting around. No, it's to retap the block after removing the remnants of the broken headbolt... I tried to match a headbolt to metric threads at the local (and well-stocked) hardware store, and nothing seemed JUST right.

But until I get the remnant of that ex-headbolt out, the point's kinda moot.

Thanks,
Jim

Sorry, I didn't communicate very well. I was suggesting that any decent NAPA store should be able to look up the info that you need.

Jim, you might try Tacoma Screw for a tap, if anyone can match up metric stuff they can. G'luck.......ed

Ahh...I get it now. I'll give that a shot. And I'd rather gnaw my leg off than go to Tacoma Screw...which sucks since they're a half mile away from me. But their service and attitude sucks. But, I might have to brave it.

That 2.8 sitting in my shop looks better and better...

Maybe it's just that particular store. They've always been pretty good across the water here in Bremerton.

A quick update for those that are following this escapade...lol.

The 2.8 (3.1, 3.4) engine family takes a M11 x 1.5 pitch thread. Kind of an oddball, M10 and M12 are all over, but not M11. And yes, I had to go to Tacoma Screw to find a tap. But it was right there out in front of God and everybody! And less than 6 bucks.

Unfortunately, Mr. Impatient (me) did a lousy job with the initial drilling out of the broken stub, and got a bit off center and off angle and scraped some threads off one side. I did find out that some K & S brass tubing and an old head make a pretty good drill jig, though, just too late.

Will be installing a Time-Sert Perma-Coil thread insert next week. Glad the v-6 is a cast iron block, I can use a less expensive kit... it's only a hundred bucks give or take. All the other kits start at $250 and go up. Eeek.

I'll report back with the results. I hate it when posters never get back with how things worked out...
<img src="/forums/images/graemlins/confused.gif" alt="" />

Well, the block is fixed...the Timesert insert kit worked great, and the threads look like brand new. Head bolted back on with new head bolts, and it's just bolting all the little bits back on. Not enough time in the day... If you're wondering, the thread insert kit came from Mechanics Tools and Bits, and Neil there was exceptionally helpful. You do need a special Loctite that almost no one carries, #266, but MTB does have it.
I wonder how this 3.4 will feel running on all 6 cylinders?