I read on here these are prone to leaking but this one was milled flat by the speed shop when I bought it and it's leaking pretty good. I snugged it up initially and still leaked, then snugged it some more, still leaked. Can someone make a suggestion on what'd work best to stop the leak...new gasket and some silicone, gascacinch, or ?? What is considered "overtightened" on a thermostat housing? Certain torque spec? Motor is 302. TIA, John
I wouldn't tighten it too much. The ears on the housing break easily. Ask me how I know! I'd take it off and get a new gasket and liberally use some silicone on it. Also lube up the bolts with the stuff. Then tighten the housing only about half way, let it set up for half an hr. or so, then tighten the rest of the way. It's worked for me before.
I finaly JB welded mine. leave the o ring on it. permatex 2 on the bolts. If I need to remove it a sharp whack will shear it off Right?? Sparky
Don't buy those chinese pieces of shit! The way to go, if you want quality, is to buy a cast iron replacement part, and have it chromed. Besides the leaks, they also rot out very quickly from the acidity of the anti freeze. had quite a few develop pinshole leaks after a year or so.
Bet they coppered it. That is generally the problem. The inside is the area shaded the rack so it doesn't plate as evenly. Differences can be as much a 3 thousands and more if it had a lot of copper. The best thing to get over it is a quality gasket with sealer on both sides. Allow it to dry for at least 30 minutes before you fit the part. Trim excess sealer just before you fit it. Torque it down and run motor enough to get hot. Torque her down again. Should be set for life. Normally for small bolts 30 to 35 ftlbs is enough.
This was a very comon problem until they started making them with the O ring. I was the only one without the problem and then I realized my cooling system was not pressurized. The O ring seems to have solved most of the problems.
I had that problem with one. I heard they were no good but I had one on my sbf anyway. Lasted a year or two, and one day it started pouring water out. I found '60's fords used aluminum ones, so I got one of those. It matches the aluminum intake anyway. I would use one painted before I used another chrome one. It was warped pretty bad, and it was flat when I put it on.
everyone i know that has used one of those O-ringed POSs has had them leak. myself included. Permatex usually does the trick. on the motor i just built for my daily i went to the parts store and bought a cast iron replacement. did'nt know they even had them available. it was pretty cheap too. the casting was quite rough but i'm no stranger to the grinder so thats no biggie. i'll smooth it out and paint it. you could have it polished and plated if you wanted chrome that bad but that'd end up costing alot unless you happened to have a bunch of stuf getting chromed anyway.
Any time you have to pull something apart to find out why it's leaking, it's a good idea to throw a glance down the bolt holes. Or maybe do it before you put it together the first time. One of those lessons that we all learn about 50 times, I suppose. Threads themselves never require sealant; it's the stuff behind the hole that's trying to spooge out that needs the sealant. If the hole goes through to coolant land, sealant will do the trick.
Throw it away...if it's a cheap Taiwanese version....it'll never stop. I put a factory waterneck back on mine and the leak went away....
Just wanted to relate an experience I had. I replaced a leaking thermostat housing that had corroded from the inside out and started to leak. After the install, I had similar symptoms, only I battled it for about year. First the new thermostat housing was warped - got another one. Then questioned the type of RTV I used (blue vs. red). Then questioned the type of gasket I was using (Auto Zone vs. Ford). Then tried varying combos of RTV plus gasket or just gasket or just RTV. You get the picture. In all scenarios, the leak would come back, as detected by my wife who can smell coolant from a mile away. The problem I had was the mounting bolts were bottoming out in the intake manifold (Edelbrock). I was using the same bolts/washers/gasket/type of thermostat housing, and figured it should all go back together just fine. And it looked/felt like I did. Each time I buttoned up the install, warmed up engine and then retightened everything, I never saw a leak. But the fact that the bolts bottomed out and lacked the last 1/2 turn needed to really tighten things up, caused the leak to return. The original install of the thermostat housing had a TON of some sort of clear RTV... which must have kept the bolts from bottoming out. So... before you apply RTV to your clearn parts, trial fit the housing with the gasket. Snug things down and make sure your bolts are engaging the intake threads sufficiently and not bottoming out. You can use washers to "fine tune" the depth of the bolts. I put a thin layer of blue RTV on both sides of the gasket and haven't sprung a leak yet. Most folks are gun shy of overtorqueing these bolts (with good reason), and with a new gasket and fresh RTV, it's easy for things to look and feel tight, and not be questioned. Even "rocking" the thermostat housing back and forth won't show any movement. I know this might seem like an obvious thing to check, but didn't see it listed here yet. -murph
The best thing is to use studs,especially in an aluminum manifold. Seal them up with permatex#2.use a thin paper gasket,to avoid warping the housing. Use perm#2 on the gasket also.IF all else fails(and most likley it will) use JB weld,like I did Spark-O
I made studs (I have an aluimnum manifold) and used the O ring, the gasket, and black permatex. No leak. More is more, right?
Y'know, I wouldn't be too frightened of Chinese or taiwanese aftermarket products. You'll find the engineering is upto snuff if it carries a respectable brand name. Unfortunately it is a fact that the chinese are now building bearings, bushings, electric motors as well as the best, if not better. Sad to admit it, but it's true. I still try to buy local or american when I can. If big industry still did the same we might even be able to compete. But evidently the biggest employer in the american auto industry is now toyota. I'm going to open another beer before I depress myself and start crying about how it used to be.
Get an 80 grit stickey back sanding dick and stick it onto something flat, like the garage floor or work bench. then sand the bottom of the housing till the whole thing is covered in sanding marks. you'll be able to see the high and low spots really easiy, and you'll have it flat in no time.
I had similar problems on a couple of SBF's a few years ago. Tried all the different sealers and gaskets; checked bolt length and trued up the mounting surface to no avail. Final answer for both engines was to throw away the chrome housing and put a new cast-iron replacement on. No more leaks.
my chrome "boca del agua" got the viking funeral... the one way flight over the hill into the old dump. leaked constantly, read a few posts on here about it, tossed it and bought a cast iron one. i'd have rathered an american one, as i prefer on everything i get, this one was chinese (didn't have a choice at the parts stores, this was a special order item for a freakin SBC in a 65 impala!!! belice that shit??) but it works. no leaks.
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