Thermostat housing replacement SOHC 2 wheel drive

[Skip Towne]

Hints or tips on how to replace the thermostat housing and related hoses. What do I need to look for?

 

[donalds]

4.0 SOHC Metal Thermostat Housing Comparison

 

[donalds]

How to: Replace a thermostat on a 2000 4.0L SOHC V6

Be sure to use very good parts
Be sure to burp the system very well if you think you got all the air out you don't

If you remove your upper intake ...I didn't....
The upper intake screws are basically hand tight

I used a torque wrench on my old one and stripped the holes
then I bought a new lower intake bc I just stripped my original one
used a torque wrench on the new one stripped it
So be careful and go slow

 

[XLTrunner]

Proper torque on intake screws are:
Upper - 62 in lbs
Lower 120 in lbs

Note: these are INCH lbs...not FT lbs. Don't make the mistake of thinking tighter is better on these; especially, on the upper intake screws as you probably will strip out at least one since they only screw into the plastic lower intake.

I can't emphasize enough to use either the Motorcraft upgrade parts or the aftermarket metal housing. I've been thru the Dorman/Four Seasons junk and you'll most likely end up re-doing the job in the near future (my Four Seasons housing lasted all of 10 days).

If you can do this job by not removing the upper intake, more power to you. I simply don't know how it's feasible on my '98. That t-stat housing needs to be lifted and lowered more or less straight up and down to avoid breaking off one of the three plastic tabs on the bottom of it (they can fall into the engine). And, the Crank Pos Sensor wiring runs fairly snug across the top of the housing on mine...so, it needs some slack to lift the housing. This can only be done by removing the alternator, alternator mtg bracket and tensioner to free it from two clips on the front of the block. Then, there is that p.i.t.a. short hose that connects the housing to the water pump. With the upper intake removed, it makes this job much easier IMO...plus, it gives you the opportunity to replace the upper and lower intake gaskets which are probably needed, anyway.

 

[donalds]

I agree it would be easier to just remove the upper intake I did strip the holes in the lower intake 2 times going by the torque specs
Then I got smart and just tightened by hand in a crisscross pattern

But I did change it by just removing the alternator . Fan . Belt tensioner. And the alternator bracket itself

I chose to upgrade to a metal housing because after doing the job like 5 times you live and learning guess

Fwiw I know the dif between foot pounds and inch pounds
My four seasons lasted less than a week

 

[koda2000]

Sometimes using a torque wrench (even with the specified torque) just gets you in trouble. I'd rather go by feel using a 1/4" ratchet on something as fragile as old plastic.

 

[donalds]

Sometimes using a torque wrench (even with the specified torque) just gets you in trouble. I'd rather go by feel using a 1/4" ratchet on something as fragile as old plastic.

That's exactly how I did it
Also you can see the gasket squeezing if you look from the side

The way I solved it was
the upper intake the screws thread in then they thread in to the lower
intake
I noticed that they were binding working against each other so I drilled yes drilled the upper intake screw holes just big enough so the screws could just fall to the bottom the threads on the lower intake tightened them up with a 1/4in ratchet works great no binding no buying lower intakes

 

[Jason94sport]

I put a new TS in before the summer. I didnt have any issues with anything. Ratcheting ratchets work wonders.

 

[Skip Towne]

My Explorer has heavy duty cooling. When I got it the coolant looked like chocolate milk. I flushed it with distilled water and put in a 16oz bottle of CLR. Drove it for 3 days, flushed it twice with distilled water, put a small bottle of radiator cleaner in it flushed it 2 times with distilled water, changed the thermostat, put in a 180° one, filled it with anti freeze and it worked great. I now have a small leak from the thermostat housing. So now I am changing all the hoses and replacing the housing. I think I will replace the serpentine belt because I plan on removing the alternator and anything else in the way