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Radiator draining from t-stat housing??

NeXJ

NAXJA Forum User
Location
Los Angeles
Hi folks...
The last few weeks I've been noticing a lot of belt squealing but was too lazy to go check it out (partly owing to the fact that my quick release handle for my hood broke off and so it's always a BIT of pain to pop the hood) - but last night I had to call triple A from the freeway since (1. I noticed that the electric fan was coming on from almost a cold start and 2. I started blowing radiator juice in the form of steam/spray out of the front of my XJ while on the freeway). so I pulled over and got it on a flatbed home. This was last night.

So today I'm looking at it - and the radiator had drained completely dry or nearly so... so I decide to start filling it up to see where the water's getting out (assuming it's not just escaping under pressure from the rad cap) and once it's nearly full, I'm seeing water just POURING out in a small but steady stream from the t-stat housing (!!!). It does not seem to come from the hose but more the underside - but not even a bad seal on the housing could possibly produce that kind of gusher (this is with the engine OFF - just filling it up)...

First I'm thinking - okay - bad water pump - but IIRC the water would be coming out of a weep hole in the WP if that were the case - NOT the t-stat housing....

Any suggestions about how to approach this??


1992 Cherokee Sport Package - 2 door, 267K miles
1999 HO Motor
3-core radiator (forgot make - it's the only one currently available IIRC)
etc
 
there are two 1/2" bolts that hold the housing on. pull those and put in a new t-stat, gasket and probably the hose too. if its the housing, go to the junk yard and get one. the waterpump is not much more difficult, just more bolts.

It really is an easy repair.
 
Well i've done my own housing and water pump replacement several times - so I'm familiar with the process - it's just that it's a new gasket and new WP (only about six months old) so I'm a little surprised and wondering if there isn't something else going on here (?). And, as mentioned - I doubt you'd be able to get that kind of flow from a t-stat housing even with NO gasket... let alone a non-pressure situation... just wondering if there isn't some kind of overflow on the t-stat housing - maybe something I'm overlooking??
 
You may be overlooking a cracked housing...

They can be quite easy to crack if the t-stat itself isn't properly seated, even just by a c-hair. If it's off kilter when it gets tightened up, the housing can crack. Sometimes it's just a hair line crack.

There is no "overflow" on the housing
 
Okay- thanks for that! It's a possibility I hadn't considered actually (!). Seems perhaps like a good idea to get a new housing and new t-stat (even though this one is less than a year old) gasket and RTV and go from there maybe...(?)
 
Can you not see where the coolant is coming out? I have a small inspection mirror for the things I can't see directly; something like that might help you here. Pay attention to the new housing if you do replace it; I bought one last week, but it wouldn't actually work. The recess for the Tstat/the radiator hose outlet was about 1/8" too shallow. The only way it would bolt up to the head, was without a thermostat. Tried three different thermostats to no avail. Compressor Works brand on the housing.
 
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Yes - well there seems to be a 'bauble' of water forming toward the base of the Tstat housing... so I assume it's coming from either the edges of, or from somewhere ON, the tstat housing... I DOUBT it's the hose connections since the rate of flow is too high...
 
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