Hello all, I'm having a problem with my bronco during initial warm up. After about 10 min. the temp gauge is on the L of normal, within a 30 seconds it drops back to the middle. Periodically it will start to creep back up but never that high and it always returns to the normal range. I replaced the thermostat, flushed cooling system, and the coolant level seems fine with no leaks. Any help would be greatly appreciated.

What degree t-stat did you put in and what kind of fan do you have and did you change / check you radiator cap

I put in a 195 thermostat, but I did not change my cap, I'll run out and get one. I have the stock fan.

Humm dunno , I always replace mine with so called performance thermostats. They will fail open instead of closed.

I didn't catch the parts store in time so no new cap yet. Do think I could have gotten a bad t-stat?

Also check the operation of your fan-clutch and look at the shaft on the back of it to see if its leaking any lubricant(dirt accumilating around it) a sign its going bad. and you did put the t-stat in the right direction right? [img]images/graemlins/blush.gif[/img]

Maybe the thermostat is sticking a little at first and then opens up completely. If it is doing this consistantly I'll bet that's it. Before I changed my last one my heat was going through the roof and then all of the sudden it would even out. Changed the thermostat and it works fine again.

the last time i changed my t-stat, i immediately began having overheating problems, so i figured i had probably put it in backwards even though i make it a point to double-check it before i put the hose back on. took it apart and nope, right direction, bad t-stat [img]images/graemlins/frown.gif[/img] so i lost trust in t-stats and put it back together without one, which is now catching up with me when it's 35° outside [img]images/graemlins/grin.gif[/img] it was a high end one too, but still failed from day 1, so it is possible to have gotten a bad t-stat [img]images/graemlins/tongue.gif[/img]

i wish Ron-Bo and the fun bunch would hurry up and make the electronic t-stat technology reliable... i figure it would be pretty easy to add a manual override to that setup so that if the electronics do go kaput, you can just crank that sucker full open like they're supposed to fail but never do [img]images/graemlins/cool.gif[/img]

Well tomorrow I'll put a new t-stat in again, cap, and check the fan clutch. Thanks for all the help and quick responses, you guys should charge for this stuff [img]images/graemlins/grin.gif[/img] I'll let you know if it works.

You can get away with no Tstat if you have a Biiig bumper the problem usually lies in that the coolant goes through the system too fast without one and thus it doesn't have enough time to let the radiator cool it down. I'd think that setup would work better in the winter than in the summer because of the cold. I think It would be a good idea to replace it anyway though. No Tstat is a good emergency fix but I wouldn't want to risk overheating. I'll bet my cousins F250 Diesel Radiator would cool it without the Tstat though! That thing is huge! I like the duel bat setup in those too. Take Care. NORM