Topic: Water Neck
in Forum: C3 Cooling and Heating Systems
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Last summer and again now I have a problem with the chrome water neck (thermostat housing) leaking antifreeze on to my Edelbrock aluminum intake manifold after the motor cools down.
I changed it from a chrome swivel type to a 45 degree stationery unit. The second unit worked fairly well until this weekend. More leaks after the motor cools down.
I tightened it with no improvement. I don't want to tighten it too much and strip out the threads on the softer aluminum intake manifold.
I'm considering going back to the stock type water neck with a standard type gasket. The "O" Ring gaskets just don't work.
Any advice & opinions are appreciated.
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Mounds View, MN - USA
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I can't see any reason not to go back to the correct housing. I always use the O ring gaskets, and put a little silicone sealer on the housing side. I can't remember the last time one leaked.
Larry
Larry
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The leak you have seems to be common with the chrome water necks. A buddy of mine went through 2 of them on his 76 before giving up and getting a cast aluminum one, that solved the leak problem. You may try sliding the mating part of the housing against a fairly course piece of abrasive paper laying flat on the workbench to true and roughen the mating surface a bit to see if that helps. Are you using any silicone on the neck?
Hey guys,
I'm looking ahead to Wednesday.
I'll try replacing the O Ring and using the silicone.
If'n it don't werk, in the garbage it goze & I'll try the cast aluminum.
Thanks for the advice & I'll let you know how I do.
Kevin
I have about 5 of those in my shop from DNV and Fireboss. Thye have not been able to keep them from leaking. Mine, on the other hand, is tight as can be.
Well, I'm back to work on this.
I went to a swap meet and bought a 45 degree aluminum water neck with the "O" Ring gasket. (No one had aluminum that takes a standard type gasket.)
So, I'll be giving this a try.
When I use the silicone sealer with the "O" Ring, how thick should I go with the silicone?
Could I create a problem if the silicone comes into contact with the "O" Ring when its snugged down & tightened?
Thanks in advance.
Kevin
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I have an aluminum adjustable o ring housing. No leaks and no silicone...
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The trick to using the chrome housing is to completely grind off the chrome on the sealing surface, preferably with a belt sander, so it will still be flat. The chrome will NOT allow a tight seal because it's so "slick"...fluids will seep right past a gasket, or even silicon. If you remove the chrome, it becomes regular aluminuminum(or steel), and a normal gasket will seal. Another neat trick is to use a little wheel bearing grease on a regular paper-type gasket...works like a champ, but even that will not seal against chrome...
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Kevin, don't use silicone adhesive with an o-ring, use a silicone grease on the o-ring itself, & in the groove, not on the metal to metal surfaces. O-rings need a good tolerance on the fit and chrome plating is thick and not always flat, so doing what Joel suggests would only help.
Dave
Lifetime Member #116
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in Forum: C3 Cooling and Heating Systems
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