Club Cobra

Club Cobra (http://www.clubcobra.com/forums/)
-   Texas Cobra Club (http://www.clubcobra.com/forums/texas-cobra-club/)
-   -   Leaking Woes (http://www.clubcobra.com/forums/texas-cobra-club/90737-leaking-woes.html)

BlueCobra 08-28-2008 04:27 PM

Leaking Woes
 
Help!!

I have a Superformance with a 351 Ford Racing crate engine that has developed a leak in the thermostat housing gasket that connects to the manifold. It has the reservoir tank on top of the elbow connector and I have replaced the gaskets with Felpro gaskets that were recommended, but that soaked up the coolant and began to drip again. I then pulled that back off and used a silicone gasket seal from a tube and that didn't work.

Anyone out there got any suggestions :(.

This should be a simple fix, but has turned into a nightmare.:CRY:

Any help would be appreciated.

Dan

scootter 08-28-2008 05:21 PM

Does it have an O ring grove or just a gasket? I used the gray RTV sealer on everything, and it worked good.
Scott

SSSammy 08-28-2008 05:23 PM

Dan, assuming there is not a hairline crack somewhere, try one more time with a new FelPro gasket. Clean the gasket surfaces on both the water neck and the manifold with a razor blade. Wipe down with lacquer thinner. Use a waterpump and thermostat specific silicone gasket sealer.

http://ec-images.acehardwareoutlet.c...092107i_pk.jpg

Smear it uniformly all over both sides of the FelPro, just thick enough to cover. Give it 10 min to get a little tacky before you bolt the water neck back on the manifold. Just snug the bolts up overnight, then the next day run them up to around 25 ft-lb, so you don't squeeze the sealant out while it is wet. Good luck!

Sam

Bob Taulbee 08-28-2008 05:58 PM

Dan,

A common thing wiht those T-stat housings are, they tend to bend if they are over tightened. When you remove it, use a straight edge to see if it has a bow in it. If so, you can use a block and some sandpaper to work it out.

BlueCobra 08-28-2008 06:33 PM

Thanks for the help.

It does not have an O ring; It actually takes the the gaskets from a 302 1968 mustang (and other models).

I will try to use the gaskets again with the silicone sealer and see if that work.

Dan

MacGyver 08-28-2008 07:04 PM

If sealer was not applied to the the bolt threads it could be leaking from there giving the appearance the housing is leaking...

BlueCobra 08-28-2008 07:42 PM

Thanks Macgyver

I did not try that; maybe that is why it keeps leaking. I'll try that when I put it back together.

MacGyver 08-28-2008 09:23 PM

I have fought that battle before only to discover the leak was around the bolt threads. This can happen on t-stat housings as well as front cover and water pump bolts. Be very carefull and check front cover and water pump bolt threads as they can be a bottom casting for the bolt hole causing a hydrolock of sorts breaking the casting when bolts are coated in areas when the hole bottoms out instead of penetrating a hollow. A friend of mine recently broke a chunk of his block off using too much sealer in an area where it wasn't needed. i recommend probing the casting with a pick first. If the hole bottoms out you shouldn't need sealer. If it penetrates into into a water jacket you should definatily seal the threads. A thin coat on all bolts should ensure a good seal regardless.

STL Mark 08-28-2008 10:08 PM

I may have your best answer. I had this same problem this week. I called two different auto parts stores - they had the same question for me, and the same answer for the solution - which has worked. Check this out -

They asked - is you water outlet chrome? I said - why yes it is.
They said it's warped.

I said - it has only 4000 miles on the new engine.
They said - no mater - it's warped.

In disbelief, I removed it and put it on the counter - yep warped.
I installed a plain old cast iron water outlet - and all is fine.

Don't bother with fancy gaskets, or messy glue/sealer - just get a plain cast iron water outlet (paint it if you want) and problem solved - forever.

Rick Parker 08-28-2008 10:41 PM

Just a thought, be sure that either the manifold or the thermostat housing has a machined recess for the thermostat to register into, one of them must have this. Put a light coat of gasket sealer on the suface of the part that has the recess, install the themostat, the gasket and let it set up for a few minutes, THEN install the neck & tank assembly onto the engine. Be careful that the thermostat does not become disloged and fall down while attaching the neck. This assumes the surfaces are flat as mentioned previously. 12-15 lb torque is plenty. All the Windsor manifolds I have seen have blind holes for attaching the neck and do not require sealant on the threads.

xlr8or 08-28-2008 11:02 PM

The chrome housings can be used but you need to sand off the chrome on the sealing surface first. I've done that a couple of times with no leaks.

BlueCobra 08-29-2008 12:43 PM

Well thanks for all of the tips.

It is a chrome housing, but evidentally it is not warped enough, because I put a fair amount of blue sealer on it and let it set for 15 minutes and cranked it down pretty tight; let that cure overnight and it seems to be working.

Time will tell.:)

scootter 08-29-2008 12:50 PM

Make sure to recheck the bolt a few times. Mine seemed to loosen for some reason.
Scott

BlueCobra 08-29-2008 04:42 PM

Thanks Scott, I'll be sure and check. I am still a little bit leary.

bigstew 08-29-2008 06:32 PM

I had the same problem with a Ford Racing water inlet housing. The leak was at the bypass hose connection. Ford did not machine the threads so they seal when tightened. It appears the leak is at the gasket, but it you have a heater hose it may be coming from the screwed in bypass hose fitting.

madmaxx 08-29-2008 07:32 PM

I vote for the warped housing. Next time it leaks put it on a flat surface and you will be amazed. Buy a new one use the gasket sealer and just snug up.

tomh440 08-31-2008 05:51 PM

One more thing
 
If it does leak in the future.

Run a flat file over the housing AND manifold area. Sometimes there is a 'raised' area around the bolt holes.
I agree with the chrome housings too, use a cast iron or steel if possible.

Tom


All times are GMT -7. The time now is 01:51 AM.

Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: