Hey guys my grand cherokee usually runs right under 210 an just recently if I'm sitting for a few minutes it goes up to about 220-230! My electric fan I have a switch made for so I keep that running and I can cancel that out! The thermostat is only a few months old also. But when the engine was warm i got out popped the hood and spun the mechanical fan, I could spin it very easily! Is that normal when the engine is warm? Could that be my problem any help guys thanks!
When you changed the thermostat did you "burp" the system? any air in the system will cause an overheat issue like you describe. Especially on a 4.0.
2004 Freedom 4.0, tow package, 3.73s, leather, rear seat removal mod, 2.5" springs, 3/4" spacers, zone shocks, IRO short arms all around, 2 inch A-arm spacer, zone extended sway bar links, JKS adjustable track bar, K&N drop in. 255/70-17 Falken Wild Peak A/T. Final lift height H/F 20 3/4" front, 21 3/4" rear.
Yep. Even without your mechanical fan and just the electric fan, since the mechnical was for extra cooling with towing, you should have heating issues at all.
The only thing a secondary switch is good for is in an emergency if it's not cooling, as in, the electric fan is not coming on. I've left mine inand working on permanently putting it in by way of a relay. You don't want it to backfeed power into the electrical.
The beatings will continue until attitudes improve!
When you connected the switch to your fan what did you connect it to?
The original relay or just direct to the switch and battery?
Do you have enough power to the fan for propper cooling?
I would guess it was a switch to the battery. It runs it at full speed when switch on. The draw back is it requires driver to watch the temperature gauge like a hawk and switch it on before temperature rises.
Its common to see this done when the relay has gone faulty. The draw back is we are human, sooner or later we will forget and by time we notice engine is already too hot and damage done.
Some users will justify the switch saying electronic relay keeps blowing and ignore the problem of a faulty fan drawing too much current because its worn out.
If the engine runs cooler with the heater on then you are not cooling enough at the radiator. Check your clutch fan, spin it with the engine off. If it spins freely then its bad.
Check the speed of your electric fan.
Remember the fans will not provide cooling while driving above 30. If it gets hot above 30 then your radiator needs flushed, replaced or the thermostat is stuck.
The best solution is to remove the switch and put all the wires back where they were (by the factory). The fan switch will NOT solve your problem. The fan relay is controlled by PCM (computer). The PCM makes the decision when to turn on the fan and when to turn it off. Get a Mopar relay (don't get non-Mopar parts). Check your mechanical (water pump) fan, the clutch should function in normal operation, if not replace it.. Check all leaks - water pump, radiator, hoses, etc. The water pump should be in good condition. If the coolant is old (more than 2 years), flush it and add Zerex G-05 antifreeze and distilled water (50/50 mix). If you bought a thermostat from someplace else, replace it with Mopar-brand thermostat. I've read many stories from this forum saying that non-Mopar thermostat, especially these "fail-safe" thermostat, is causing problems (overheating, etc). It's best to stick with Mopar parts only.
Last month my radiator leaked, I replaced with many Mopar parts (hoses, clamps, radiator, fan relay, etc). Now, it runs at 205-208 degrees, even during the 100+ degree days, while sitting at idle at red-light traffic. I don't use worm-type clamps for the radiator hoses because they will not "expand" when it becomes hot. I use Mopar clamps, they always expand when it's hot, and shrinks when it's cool. Not a drop of leak using the tension-type clamps.
2000 WJ 4.0L, drop-in K&N filter, Addco rear antisway bar, Bridgestone Revos, Overhead DVD monitor w/ wireless headsets.
2007 BMW 335i, Montego Blue with Lemon seats, premium & sport package.