heat

[barmanjay]

Third one since October...I can't see going through 3 faulty units that stick open in a row. 
Ah well...I'll try a few things as suggested on the board here...and drive the OTHER vehicle when it's < -20. 

maybe give your system a flush?,.. could be some crap in there that's making your t-stat stick.

I had that issue in another vehicle once,.. soo much crap from a previous blown gasket, went through 3 t-stats, until i flushed out the rad and system with my garden hose. (tipped the rad on it's side and ran the hose through it)

side note,.. -18 the other day and I had to turn my heater fan down cause I was getting too hot.

[RedApe]

maybe give your system a flush?,.. could be some crap in there that's making your t-stat stick.

Full flush done in Aug...but great suggestion.

[Gearhead]

I have read a mod somewhere where you replace the factory fan with one from a Chev. Do a search for it on google or try to contact Tim Garton(somethingwicked). I'm pretty sure he did it on his YJ.

Oh yeah, cardboard on the rad always helps.

Some comments to add.

This mod only applies to earlier YJ's  , the 91 ?  & up has a larger fan already.

Winter front is a good idea and helps.

DO NOT    buy a "failsafe" thermostat , they are crap and will fail in a very short time period , they fail open  , , alllowing full flow of coolant , OK in the summer , hence the "safe" part. They always fail in the winter due to wide temp variations. I've been through this several times and will not waste any money on one  again . Stant makes a premium thermostat which holds up well , they're called "superstat ", a heavy duty version of a normal ( cheap ) T stat.

Bottom line ,  a  4 banger does not make a lot of heat .