Thermostat housing to frnt hose leak

[smcdermott326]

On a 89 ix, the coolant hose attaching to the front of the Thermostat housing (part #11531730470) going towards cooling fan keeps leaking past the clamp no matter how tight the clamp is. I've tried several different hoses both aftermarket and OEM, replaced the housing itself with OEM, tried several different clamps including OEM and aftermarket and it still leaks past. This has been going on a couple of years now and my last attempt at coating with some high temp black sealer (permatex 501?) also failed to stop the flow. It's not pissing out strong or anything...more like weeping out, but annoyingly giving some small puddles, and so I have to add every now and then.

Any tips or techniques to share or someone with similar experiences?
Thanks!

[jlevie]

While it isn't uncommon for corrosion of the housing the make it nearly impossible to obtain a leak free connection, a new housing will fix that. Since you have replaced the housing and the hose I have to wonder if the leak is really from that connection. The water pump is just below that point and could be leaking.

[smcdermott326]

yeah it's from that connection. I know what you mean about the corrosion, which is why I replaced the friggin thing, hoping to solve things. I'm using a telescoping mirror to see it and have done leak detection dye's with black lights too. I've had a lot of practice over time, both from above and below the car.

[jlevie]

The only things I can think of that could cause a leak there would be a bad casting on the tstat housing or excessive pressure in the cooling system from a small head gasket leak. Of those I'm more inclined to suspect the housing as a head gasket leak would be causing other symptoms.

[smcdermott326]

Ok. Makes sense. Maybe it's time to swap for a used casting that was used tried and true on another vehicle. Thanks for the feedback!

[jlevie]

That or get a new housing from your dealer. If that is where you got this one and examination shows porosity, take it back and they'll swap it for a good one.

[smcdermott326]

ok. I got it from BavAuto who I think does a 1 year warranty of some sort. I'll check into it, thanks!

[Alpinweiße30]

get coem clampco t-bolt clamps. Click here. If you don't know about McMaster-Carr you should. you can get just about ANYTHING here. I use it a lot at work.

[smcdermott326]

thanks for the tip!