SOHC Thermostat Housing...

[Robman]

I keep a 2000 4L SOHC sport 4x4 on the back burner as a spare vehicle, it's got 194 000kms on it and of course has the start up rattle.

I took it for a short warm up drive today which I do with all my vehicles that don't see regular road use and after a short time started to smell antifreeze and belt started to slip causing my voltage gauge to read very low.

I haven't looked into it very far yet as I've just popped the hood and there's coolant everywhere but I remember something about the thermostat housing on these things being crappy, can anybody elaborate on what likely went wrong with the housing? Thanks and btw: I now have another reason to hate the SOHC.

 

[swshawaii]

Lower t-stat housings usually split at the sonically welded seams. IF you have threaded sensors, here's an upgrade.

4.0 SOHC plastic thermostat housing | Ford Explorer and Ford Ranger Forums

 

[Robman]

Thankyou for the input, however I just found the problem, originally I couldn't see where it was leaking out because all the coolant had already drained.

There's a very short hose, maybe 3 inches long that connects the lower part of the thermostat housing to the water pump and it bulged and blew a hole. It's in a very inconvenient spot too, lol.
I'll grab a new thermostat while I'm at it.

The OHV design even just for this part seems to be much more reliably designed.

 

[swshawaii]

Oh yeah, that EVIL and short water pump bypass hose. Knuckle scraper, constant tension OE hose clamps are no fun.
Use a bent needle nose plier if you have one. Take your time, many have replaced it with a "few" four letter words. GL

 

[Robman]

Well, after taking the intake/airbox tube and idler pully/belt off I managed to get the old hose out(in pieces) so there's job 1 complete. When I get the new hose I think it's going to be a pain still as there's very little clearance between the water pump outlet and the lower thermostat housing, maybe 3/4 of an inch to get the hose in and on.

 

[RandomNerd2000]

You might as well plan on replacing the housing too, they don't approve of being taken off and put back in old age and when mine failed I had to remove the housing, and then replace it 200 miles later.