454 Getting HOT

[Mild Thunder]

I got a 1989 Dually crew cab. if i sit in traffic or idle too long, the temp creeps up to 230 ish. Once i get rolling down the road, eventually it cools back down to 210... Sometimes going down the highway its at 160....

The fan seems to be working. With the engine running its spinning, and i can hear it. I got a new T-stat, havent put it in yet though. The upper hose is hot though.

It also has a electric fan behind the grille, and what looks to be a big oil cooler. That fan never goes on. Is there a switch for it?

[beastie_3]

Only you will know if there is a switch for the electric fan, it never came stock. You should check the fan wiring to see if it is getting juice. Then trace the wires to see if it leads to a switch or a thermostat switch. You said the fan seems to be working, but later said it never comes on?

[Mild Thunder]

Sorry, what i mean to say was the clutch fan seems to be working fine. I thought i had read somewhere that some of the 1 Ton Duallies came with the auxiliary fan from the factory. The harness for it looks like a OE connector on it...

[Irish_Alley]

seams to me that it may look like its working but its not or your fluid is low ex since your not moving the fan is supposed to do all the work and pull air over the rad fins and at higher speeds the truck will push the air over the fins but in your case the fan isn't working up to full speed maybe moving just not fast enough. but check your antifreeze first see how low it is then go from there

[Mild Thunder]

Replaced T-stat today, with a stock 195 one. Same issue. Then removed stat, and still got 210-220 idling, prob woulda climbed higher if i left it run. Then did a complete flush on the radiator/engine, etc. Although the coolant was a nice green, i still got lots of rust sediment and crap in the drain bucket. Let it idle for about 25 minutes with the a/c on, and hottest it got was 160. Im guessing the radiator and block was full of crud...Clutch fan is working, and got the elec fan to work. Someone had disconnected the relay for it, and jumped it. Although before the flush, even with both fans, it would still get hot.

Should i just leave the stat out? I dont drive it in the winter, and will be towing a heavy trailer in the summer. Or go with a 160 stat....

[micahadams]

I had similar problems. Try pulling the bottom block draim plugs and see if any crud comes out. I had SO much rust that when I pulled mine no water came out. Also make sure your lower rad hose isnt colapsing. It shouldnt at idle, but check is anyway.

The bottom drains are near the motor mounts and are NPT plugs. That will at least tell you if the cooling system is clean. Also, pull the radiator and flush water in from the cap side and let it drain out the upper hose.