Last time I changed out my radiator, I elected to start taking out the inoperable ac system, at that time being the condenser in front of the radiator. There have been other oddities with my cooling system as well, but I'm trying to rule out any other possibilities. The truck stays cool just fine while moving, but is hit or miss when parked or in slow moving traffic. Is it possible that the absence of this other heatsink, so to speak, is the reason for the seemingly insufficient cooling system?

"Last time I changed out my radiator"
^
Is this like a bi-annual ritual?

Fan clutch is probably roasted. Does the coolant resemble mud?

lol okay well, about the radiator... I had replaced it initially about a year ago, due to a leak. and at the beginning of this year in lieu of coolingproblems starting with the fan motor going out, it overheated to the point that I blew a hole in the side of it, so I had to replace it again. not paying attention sucks. that being said, radiator is brand new, water pump is recent and is going, fan motor is brand new and blowing hard, thermostat was removed to troubleshoot and left out, as I am in Florida anyway... the coolant visually looks okay, and most had been replaced anyway due to repairs. I suppose the cavities and plumbing could have a nasty film on it inside? how do I fix that? any way other than simply flushing the system?

Cooling fan motor replaced I gather .Is this the multi speed model ?

Possible issue.....http://www.jeepslimited.com/index.ph...=37&Itemid=127

it is the multispeed, yes. the relay is working as it should, ive actually replaced it enough times that ive made a slight modification to better accomodate an extension and socket. all the components within the system seem to be working as they should. maybe the system simply needs to be flushed that badly from way too many overtemp situations...

This may sound strange to you, but anyone who has done any racing will tell you it's true. It's possible that without the thermostat, the coolant is going thru the radiator too fast to give up it's heat. You need the thermostat to restrict flow to allow time for heat transfer to occur. The PCM also needs normal temps to function properly for mixture control and timing.

My friends and I did some dirt track racing and ran our car without a thermostat. We had lots of overheating problems until an old driver asked if we were running a restrictor. A what? He told us to take the guts out of a thermostat and install just the ring. Quess what! No more overheating!

Give it a shot. Put a 195* thermostat in it and see if it makes a difference.

Yes, definitely run a tstat.

Okay I will try to get one in there. but these problems were present before the thermostat was removed...? all that did was lower the operating temperature while at speed...