Possible t-stat housing or water pump leaking... can’t get a good view angle

[3xowner]

2000 rwd with 4.0 soho with ac.

i have a coolant leak which appears to be coming from the right side (pass) of the pump. I just can’t get a good look at it to really verify it. I am thinking to pull off the alternator, alt bracket, and tensioner just to verify it. May put everything back on after verifying and then do the job maybe a week or two later. Thinking to verify it this way may take me about 2-3 hrs totals.

Thinking if I do verify pump is the leak (gasket) that I would want to replace fan as well.

Thoughts?

 

[koda2000]

While it might be the w/p, on a SOHC it might be a crack in the plastic t-stat housing, which is very common. If you have to replace the t-stat housing you should consider an all metal replacement (around $150).

 

[J_C]

I too would look closely at the thermostat housing first, but if I were going to pull parts for 2 hours to look at the water pump, I'd go ahead and replace it while I'm that far in, considering that it's 18 y/o, unless you were going to leave it disassembled until the pump can be installed.

However I doubt that it'll take 2 hours, maybe not need disassembly? Do you have a telescoping inspection mirror and a strong LED light?

 

[3xowner]

Doubt it’s the housing, did that 2 years ago. It’s just seems that the location of the leak on it is such a tucked away spot, that even a mirror may not help bc of alt mount bracket.

I prefer to use motorcraft parts, have one vehicle at the moment, so taking it apart and waiting on parts is not preferred. Also I hate buying things ahead of time from say rockauto without proving them bad.

I may try again harder with a mirror, just have to find where mine is.

 

[XLTrunner]

You can have that alternator, tensioner, idler pulley and bracket off in 30 mins tops. And, you'll have a very clear view of the pump...as well as the t-stat housing. Very easy to access it all. Don't forget to check the water control valve that's down in that vicinty. They will leak, also.

 

[3xowner]

Well I’ve got the alternator bracket off and sure enough the leak is around the thermostat housing unit again. Seems the heater hose had a slight leak at the clamp and seems possibly that the base of housing’s gasket must be seeping too. Shall see what I will do after lightly tightening housing bolts to block...

 

[koda2000]

Well I’ve got the alternator bracket off and sure enough the leak is around the thermostat housing unit again. Seems the heater hose had a slight leak at the clamp and seems possibly that the base of housing’s gasket must be seeping too. Shall see what I will do after lightly tightening housing bolts to block...

You're probably going to end up replacing the t-stat housing. They seem to all leak at some point. Bad design. I wouldn't bother installing another Motorcraft plastic part when there are now metal one's available for a few dollars more.

 

[allmyEXes]

Last September I thought that I had a water pump leak. I removed the upper intake to get a better look. The thermostat housing was rotten (222,222 miles on it). I'm a penny pincher and purchased this one and it is still working. Comes with new sensors
New Thermostat Housing W/Sensors for 1997-2001 Ford Explorer Mountaineer 4.0L | eBay
I know it is cheap, but at that price, i'm willing to put another one on in 2 years if I have to

 

[J_C]

^ That is a crazy low price for that, to even include sensors.

 

[3xowner]

thats is a cheap price.. almost cant believe it.

Koda2000, do you have a link or source for the metal ones?

last year I replaced mine with one I got at junk yard, looked real good and no coolant leak scaring on the junked unit.
Right now, i had been adding about a pint every 100 miles while I have the radiator cap half turned (8-10 lbs maybe). Hopefully and 1/8 turn on the 3 main housing bolts will slow it down for awhile.

Motorcraft had these for like 500 or 700 bucks. Guess my design for the 2000 explorer 4.0 SOHC is that one the the sensors are not removable, blah blah...

i had the original housing leaking for 4 years... back t-stat housing bolt sleeve was damaged, probably from dealer doing 60k service and owner requested t-stat replacement. I may pause a bit to see severity (coolant cost) going forward vs cost (of quality part) and the effort. looking to get another 47k over 2.5 years to get me to 225k then I am done with it and need to move on.

 

[allmyEXes]

And my budget one came with the thermostat too. I was hesitant but I knew that it had to be better than the original one that removed that crumbled upon removal. Also 9 months ago I installed a brand new Made in China alternator on my 5.0 Mountaineer. $96- ROCKAUTO. The local parts store wanted $170 exchange. It works well. Yesterday I purchased a brand new window regulator with motor for my relative's 2010 Crown Victoria at O one of the big 5 parts houses. I can't remember if it had made in China on it but when I took out the "factory" one, it had printed on it Made in China. On my part in my "American" made Ford ? LoL. You wouldn't believe how many American auto parts are outsourced to foreign countries. Last Saturday I was working on my '97 explorer power window motor and the big harness in the door had a made in the Philippines sticker wrapped around the harness.
Again, I took a chance on the $18 thermostat housing with the thermostat in it, and it works. I have been driving it everyday for 9 months since I installed it. Don't overtighten it or it will crack and leak.

 

[koda2000]

Link to metal t-stat housings:

This one is for a Sport Trac (not sure what the difference is, but they have them for all models of SOHC's. (simmonsautosportz.com).

2001-2006 Explorer Sport Trac (2 sensor) Metal Thermostat Housing (SA4)

 

[koda2000]

Last September I thought that I had a water pump leak. I removed the upper intake to get a better look. The thermostat housing was rotten (222,222 miles on it). I'm a penny pincher and purchased this one and it is still working. Comes with new sensors
New Thermostat Housing W/Sensors for 1997-2001 Ford Explorer Mountaineer 4.0L | eBay
I know it is cheap, but at that price, i'm willing to put another one on in 2 years if I have to

That price is nutz. I wonder how they can make them, include sensors and ship them for that low of a price, but hey if you've got a vehicle with over 200k and are on a tight budget why not try one.

 

[3xowner]

I wonder if the prices are reflecting lower demand as these SUVs are nearing end of life.

 

[koda2000]

I wonder if the prices are reflecting lower demand as these SUVs are nearing end of life.

IDK, but I was just reading the eBay description on the $18 replacement and not only does it include the two sensors, but the thermostat. The Motorcraft thermostat (which seems to be the only one that works the way its supposed to in these engines) cost me over $30 through O'Reilys.

 

[3xowner]

just to wrap things up for me on this thread, I finally replaced the housing (again). the leak started to be a little more than what I was willing to live with. I do believe that originally on this junk yard motorcraft housing that i had on for 2 years was leaking around the sensors, but i think when I attempted to snug things up months ago that perhaps a bit more torque was put on the housing's front bolt near the t-stat. From the sleeve collar at the base there was a crack and coolant was streaming out of it.

Because of when I had the opportunity to do it I went with the Murray brand from O'Reillys. With sensors coming with it and a separate t-stat out the door it was $186. Would like to perhaps saved a little more or risked value considerations with a Motorcraft OE online from distributor for $360.

I hate this replacement job. but it is getting easier each time, lol

 

[XLTrunner]

Yeah...we all become a little wiser and more proficient after changing these several times. Glad you've got it under control. My latest Motorcraft upgrade housing replacement has been holding firm for over a year now...so, holding my breath that I can finally put this behind me.

 

[koda2000]

No way I'm putting another plastic t-stat housing in my ST after the engine is rebuilt (Motorcraft or any other brand). IMO they're just a failure waiting to happen.

 

[3xowner]

i just didn't have great info on converting it to metal and the sensor considerations. then its like cost vs future mileage... blah blah blah

 

[koda2000]

Search the forum for metal t-stat housing comparisons. There are 2 different manufactures. Simmons and Austel. Simmons is a one piece design and Austekk is a 2-piece design. There is no "conversion" involved, just replacing plastic with metal. Personally I like the Simmons, but the Austekk is less expensive.