Thermostat housing / water neck recommendations?

[Rust-O-Matic]

I just picked up a new thermostat housing from O'Reilly's in yet another attempt to stop the small leak that I can't seem to get rid of. It appears to be a cast iron, stock type affair, that is proudly stamped China on the bottom.

I scraped all the old crap off the opening on the manifold, ran a file over it to make sure it's good and flat, put a VERY thin coat of permatex t-stat rtv on each side of a new Fel-pro gasket, dropped a new thermostat in, put the housing and gasket on, and finger tightened the bolts. Then i let it sit for an hour per the sealant instructions, before tightening to 25 ft lbs. I know torquing water neck bolts is a little anal, but I've had so much trouble with this damn thing I didn't want to leave anything to chance. I tightened one side half a turn, then the other side half a turn, then the other side, and so on. Before I even got to the the 25 lb setting, the housing cracked wide open. Now all the time I spent painting the neck, cleaning.the manifold, and making sure everything is just right was a complete waste.

So, my question is... now that I have to get another new neck and start over, what type would be of better quality? Would a cheap GM aluminum one be better, or are they cheap Asian made crap as well? I don't really wanna spend a fortune on anything fancy, I just want something comparable to the original quality. The old one had been on there 40 years, and been tightened so hard they stripped the threads out of the manifold (which I got the pleasure of drilling and putting in helicoils). I can't believe the new one broke so easy. I don't know if I can even take it back, because I'm sure the guy at the counter is gonna be like "uh, you tightened it too much, dummy".

Oh, and my truck is actually a '66, but the engine is a late '70s small block so I thought maybe this would be the best place to ask. Sorry for the long drawn out story, but I'm aggrivated and wanted to tell exactly what I've done in case I've overlooked something stupid. I've done this a number of times and never had this much trouble.

[Dead Parrot]

I am currently using a cast iron housing on mine and a matching Felpro gasket recommend via this forum. I think the gasket is the key. The housing was a China part from one of the box store parts places. Enough years ago that I don't remember which store or which part number. It doesn't have any taps in the housing. Reused the gasket when I changed thermostats. Still no leaks.

I spent several years trying versions of the chrome plated o-ring type housings. All wound up warping and leaking.

China parts and tools have very inconsistent QC. One batch can be very good, the next batch can suck.

[tucsonjwt]

I think I got mine from NAPA because the other replacement was impossible to seal. The NAPA one was aluminum and I used a lot of Right Stuff sealant to finally get it sealed. I think the mating surfaces are more porous than you might think, whether cast steel or aluminum. I find with a lot of sealant applied to the surfaces you don't need to torque it down very much. It does not look pretty but it works. I have a 454.

[cadillac_al]

Another case of the cheap clicker torque wrench strikes again. I have read many threads of bolts breaking waiting for the click. I broke a couple myself years ago and the clicker hasn't been out of the case since. I wouldn't give it to anybody I liked. I always tighten thermostat housings to wrist tight with a 3/8 ratchet; not that critical. If it did weep I would give it another 1/4 turn.

[Rust-O-Matic]

Thanks for the input, fellas. After sleeping on it I think I'm gonna go ahead and order a couple GM #10108470 housings and try again. They're super cheap, but several others on this forum and others seem to have good luck with them. Oreillys and Advance/carquest don't seem to carry anything but the same basic housing I just broke, or cheesy Asian chrome ones. I'll pass on both. I read a couple other guys recommend Napa housings, but I don't have one near me.

That's a fair point about the torque wrench. It is a cheapo, but has been used over and over on several other vehicles without a problem. I actually chucked the square drive in a vice and checked the settings by hanging various weights on the handle when I got it, and each one clicked very close to when it should have. I think I'll tighten the next one down with a standard 1/4" drive ratchet just to be on the safe side.

[tucsonjwt]

In the aerospace industry, click torques are required to be calibrated frequently - about every 3 months, as I recall. For guys like me who use a torque once every two years, I don't think recalibration is necessary.

I bought 1/4" and 3/8" drive clicker torque wrenches from Harbor Freight a few years ago because they had good reviews. They seem to work OK, but I only used them on non-critical parts, like valve cover bolts, so I could not testify to the accuracy of the torque limit. I crank the wrench very slowly before approaching the torque limit because I am nervous about over-torque.