Leaky Thermostat Housing - Solved

Drove my 96 v6 from MD to AZ because I finished up my contract in the Marines and moved to AZ. About a week after arrival I noticed something leaking. Upon closer inspection its definitely coolant mixed with a little bit of oil.

The weird thing is that there are literally no other symptoms. If it wasn't for the leak I wouldn't have known anything was wrong. It's a very slow deliberate leak and there are no lights on or a change in the power.

Also I'm at 226k miles. If it is the head gasket would it even be worth it to fix?

 

if its leaking outside the engine then it might just be a water pump, freeze plug, or heater hose connection leak mixing with oil leaks from the engine.

look at dip stick, is there water mixed with the oil or is it milky?

look inside radiator, do you see oil mixed with the coolant or is it milky?

where is this leak dripping from?

 

It's hard to see but it looks like its leaking from right under where the dipstick is or from that general area. I didn't notice any milkiness in the oil when I changed it the other day. I'll take a picture to try to better explain it.

 

Couldn't get a good picture but that's right under the dipstick

 

im not that familiar with these engines to know whats in this area but others will be able to help with that im sure.

change your misleading thread title so you get more help, call it "help needed finding coolant leak from engine" and you should be getting more replies soon.

im guessing it "might" be the water pump or thermostat area that's leaking

also, fill in your account details (the blue box down there under your name) to say the engine your truck has. see how mine is done? it leaves no doubt about what I have when im asking for help with anything

 

Good idea

 

at top of page there is a link on the right (thread tools) that lets you edit the thread title

 

OK I was looking for that lol

 

That be the t-stat housing. It bolts to the water pump so technically it could be the pump gasket or the t-stat gasket (more of an o-ring) or both.
If it's the original pump (not likely) it uses RTV instead of a gasket. They always leaked and the pumps were changed to use a gasket around 00-01. They interchange and I doubt they even still make the old style.

 

Before you do anything.......CLEAN THAT ENGINE. LOL! Gunkmania.

 

X2 it's very unlikely that coolant and oil is leaking out of the head. Most of the time its internal and will cause a overheat condition. Use a pressures tester to see where the coolant is leaking from.
If oil and coolant are not mixed together it's most likely not a head gasket. Good luck

 

What do you recommend for cleaning it? I've been wondering about that since I bought it but I've had much more pressing issues to attend to.

 

Go to a car wash and pressure wash it. 5 minutes of your time. Try not to spray the alternator just the real grimy spots.

 

Use a pressure washer first to get the big stuff off. You can then spray on a degreaser and let it sit a while to break through the grease, oil and grime; then pressure wash again. Try not to blast electronics, plastic or rubber with the direct stream

 

Thanks for all the tips, you guys are always a huge help.

So if it is something other than the head gasket like an o ring or something besides the water pump, is that something I'd be able to do myself? Replacing a water pump is outside of my skill level as I don't trust myself with doing the timing belt.

 

Car wash pressure wash to get the big gunk off and then spray it down with Simple Green and let it soak for about 5 minutes and rinse off. You will probably need to wipe some areas off, but that should get it looking pretty good.

That does not look like a head gasket. Probably water pump and/or thermostat housing. Once you get it cleaned up, you should be able to see better where the leak is coming from. Good luck!

 

that looks like the thermostat housing

 

The thermostat and housing is not too big of a job, but I would say that if you are not comfortable with any job - don't start it. If you have a family member or friend that is mechanically inclined, see if they would be willing to work on it with you. If not, find a reputable shop.

That being said, there is a wealth of information here on TW and you can grab a Chilton's or Haynes manual for your truck and have step by step instructions on how to change a water pump, timing belt, etc. First things first, be sure your truck has a timing belt. IIRC, the 96 4 cyl had a chain, and if it has a 6 cyl it is a belt. Maybe some of the other 1st gen folks can chime in and correct me if I am wrong.

 

You are correct, for 1st gens at least:
4-cyl - timing CHAIN
6-cyl - timing BELT

 

Just wanted to follow up, you guys were right (per usual) and it was in fact the thermostat that was leaking. I replaced the one that was in there with an OEM one and new O ring as well as scraped the part that connects it to the hose because there was some sort of residue or something on it. The leak has stopped and all is well. Also flushed my radiator while I was at it and found out that there there is a metric shit ton of rust sediment floating around in there.