SOHC 4.0 thermostat housing upgrade

[cbxer55]

I didn't have to remove the radiator outlet to get it on my Mustang. Yeah, had to finagle it a little to get it on, but it wasn't anything special to do.

My aluminum housing didn't come with a thermostat. And two of the bolts on the stock housing, the inserts spun. So I couldn't get the original stat out without having to drill out the bolts. Although I am capable of drilling out bolts, do it every day on my job, I just didn't feel like fiddling with it.

 

[DILLARD000]

I didn't have to remove the radiator outlet to get it on my Mustang. Yeah, had to finagle it a little to get it on, but it wasn't anything special to do.
My aluminum housing didn't come with a thermostat. And two of the bolts on the stock housing, the inserts spun. So I couldn't get the original stat out without having to drill out the bolts. Although I am capable of drilling out bolts, do it every day on my job, I just didn't feel like fiddling with it.

Depends on the ThrottleBody+Intake style; some have more room, others are a PITA tight space to work the TStat housing under.

 

[cbxer55]

Depends on the ThrottleBody+Intake style; some have more room, others are a PITA tight space to work the TStat housing under.

Mine is pretty close. Could've taken the throttle body off easy enough. But I manager to twist and turn it just so, and it went in. Haven't had another problem with leaks since.

 

[gw33gp]

I am going to be replacing the water pump too, so I should have plenty of room to R&R the thermostat housing without having to remove the radiator outlet. The last time I did it, I removed the intake manifold and throttle body. That gives plenty of access, but I understand taking off the idler pulley for the serpentine belt also provides good access.

I agree, it is a good idea to open the thermostat housing to make sure it is a good quality one. I always use the heating water with a thermometer method to check a new thermostat for proper function. So, opening the housing will give me the opportunity to do this.

 

[gw33gp]

It looks like I will not be using the thermostat the came with the aluminum thermostat housing. First of all, there is no brand name on it, and it has a 92C (198F) rating on it. Testing showed it began to open at almost 210F and Ford spec is 205F. Ford spec for fully open is 188-198F and this thermostat was almost fully closed (during cool) down at 198F.

I don't know why the begin to open temperature is higher than the fully open temperature but I am guessing it is due to a delay as it is coming up to temperature.

 

[sgtsandman]

I didn't get the one you got and I bought an OEM thermostat. I believe it is a 195 degree thermostat but the above 192 comment could be correct. My engine tends to stay around 195 when fully warn and running steady on the highway. It doesn't go over that unless it's a long steep hill or I'm hauling a decent load. Then, it could break 200 but doesn't go terribly high. Nothing an oil cooler couldn't fix but it isn't pressing enough for me to worry about.

 

[09 Anla'shok]

I know this is old but, has anyone had a difficult time getting hoses to seal at the heater bypass nub of the housing? Mine seeps no matter what clamp or position.

 

[DILLARD000]

I know this is old but, has anyone had a difficult time getting hoses to seal at the heater bypass nub of the housing? Mine seeps no matter what clamp or position.

Can try doubling up on the WormClamps, 2 on both ends. Not a lot of working room around that short little hose, but have it that way on all hoses here on this 2001 4.0L. Make sure to use good quality clamps and that nipples/barbs on both the housing & pump don't have any rough or chipped spots.

 

[DILLARD000]

If you've still got a plastic TStatHousing. It's always a prime suspect for a crack and leak.

 

[09 Anla'shok]

If you've still got a plastic TStatHousing. It's always a prime suspect for a crack and leak.

Thanks. Forgot to include, this is with the aluminum housing. After my second plastic housing failure I luckily found this thread to guide me

 

[Saddle Tramp]

I didn't have any trouble with mine. Wish I knew what to tell you.

 

[sgtsandman]

I know this is old but, has anyone had a difficult time getting hoses to seal at the heater bypass nub of the housing? Mine seeps no matter what clamp or position.

I didn’t have a problem. How old are your hoses? They might have lost their elasticity due to age.

Other thing is the housings have a fairly rough finish on them, It’s possible one of the seams from the molding process didn’t get smoothed out as it should have.

 

[DILLARD000]

A lite Grinding or Wire Wheel, plus quality WormClamps. Get rid of original SpringClamps.

 

[09 Anla'shok]

I didn’t have a problem. How old are your hoses? They might have lost their elasticity due to age.

Other thing is the housings have a fairly rough finish on them, It’s possible one of the seams from the molding process didn’t get smoothed out as it should have.

Thanks for the reply. I replaced the hoses with Motorcraft hoses for both heater bypass, upper and lower. I read the post about getting the bigger o-rings for the sensors as well as using the original clips. I tracked the leak down to the sealant that holds the upper bypass nipple into the housing. Also, now my sensor and plug are leaking. I think I just got a badly machined part haha! Looks like I'll be tossing this part into the recycle bin with the empty pop cans! Thanks for the replies guys.