Some of you may remember that I've had issues in the past with my Ram running hot. Here's a recap of everything I've done:
- Engine rebuild and installed a 2-core radiator
- Replaced the 2-core with a 1-core stock aluminum radiator
- Replaced the rebuilt water pump with a new water pump
- Double checked the 195º thermostat to insure it opens properly (it has a bleed hole)
- Replace the radiator cap with a properly fitting 19lb cap
- Replaced the heater core which was riddled with pin holes and was leaky
- Replaced the defective fan clutch

I have tried to bleed the air from that thing until I'm blue in the face and it will still run at over 200º if the outside air temp is over 75º. This past weekend I haul home a VW on my trailer, and it was running about 230º and blowing coolant. I had to pull over in a traffic back-up so I wouldn't overheat as the needle was approaching 250º. So long as I'm moving I am OK, but when I stop is when she gets hot.

There is no coolant in my oil and I'm not getting a sweet smell nor any moisture in my exhaust, so I can rule out a head gasket leak. I've pressure tested the radiator and no issues. Also, I've noticed that when the truck cools down it is not sucking coolant back into the radiator from the reservoir. When I stop and pop the hood, there's air burping into the reservoir.

I have a theory that my transmission is running so hot that the transference to the radiator isn't enough to cool it off. I am planning to get the transmission rebuilt this fall and will install an external cooler, but as for now I am completely baffled.

 

Can you see coolant flowing in the radiator with the cap off? Have you checked the hoses for any blockage? You've replaced everything on it but did not mention any hose replacement.Rad and over hoses could be blocked.Long shot,but i've seen it happen.

I also remember reading something about 97 Ram having a TSB about installing a new Viscous fan drive.I think it was for vehicles with snowplows though.But it couldn't hurt to look into it.

 

The hoses were brand new after the rebuild. I've had them both off and they are clear. I double checked with the engine shop that tanked the block, and they assured me that the coolant passages would be clear. I know that I have the correct intake and head gaskets installed, so I've ruled out a gasket blocking a coolant port. If my garage were freed up and I had an extra vehicle I'd be yanking the engine for a complete teardown. This has been driving me batshiat for almost two years.

 

Here's the part number on the Vicous fan drive I was telling you about.

REPAIR PROCEDURE:

This bulletin involves replacing the viscous fan drive with an improved part for snowplow applications.
NOTE : INSTALLATION OF THE IMPROVED VISCOUS FAN DRIVE WILL CAUSE THE ENGINE COOLING FAN TO OPERATE MORE OFTEN.

1. Replace the fan drive with p/n 52028837AA. Follow the applicable procedures in the service manual for the vehicle you are working on.

2. After installing the new fan drive, start the engine and operate it at 2000 rpm for 2 minutes to pump fluid into the new drive assembly.

It may be worth looking into.

 

going backwards arent you? your reducing the cooling capacity... my jeep had a 2 core which barely kept up IMO, should have been a 3 core. never any problems in the ram but it had a 180* t-stat

 

I remember seeing that TSB, but honestly I don't think it applies to my situation. Then again, I didn't install a high dollar viscous unit either when I'd normally have gone towards heavier duty parts.

 

It couldn't hurt.If this has been going on for the past 2 yrs,you really have nothing to lose at this point.

Try it out and see if it helps.

 

I missed your post. I went from a 2-core brass to the 1-core aluminum because a radiator guy told me to go with what's stock because aluminum transfers heat better than brass. He also bet me that the cores are not the correct size, which cause constriction. I'm going to talk to another radiator guy I met and have him inspect the 2-core radiator. I wanted the 2-core for increased cooling while I tow.

I refuse to run a 180º T-stat because these things did not overheat off of the showroom floor. There's definitely another issue that's causing the truck to run hot.

Oh, I forgot to mention that the oil impregnated board that's on either side of the shroud has been torn, with the piece on the driver's side gone. I'm thinking this set-up is like the old Air Cooled Volkswagens in that if any of the cooling tin is missing then the engine will run hot.

 

I took those side thingy's (technical term of the day) off on the 2000 ram I had.

What I was getting at with the Rad is that the stock rad is a 2 core, going to a 1 core regardless of the material will decrease the cooling capacity, meaning the cooling system as a whole cannot keep up with the heat generated by the motor. I'll bet you have what I'm talking about in the 2 core rad... and we're just not on the same page.

 

Mmmmmmmm, the stock radiator for a 1997 1500 is a 1-core aluminum. Either way, the truck's been running hot with both the 2-core and the 1-core.