any way to stop overheating problem on this van it is a 318 cid the doghouse set between the seats 2 feet back from the dash it has a new stat, rad, splash pan is in place. any info will be helpful
Is water circulating through the radiator? Twice, 318 engines with strange cooking problems turned out to be the water pump impellers free wheeling on the shaft. They would bind enough to pump a minimal amount at idle but the engines overheated badly when driven even at moderate speeds.
When I was a youth our family bought a new Dodge A100 Sport Van as a family vehicle to tow a trailer. This was the first year that Dodge offered the 318 in place of the 273 ci V8 or slant 6 engines. On the first outing the engine overheated and had to be towed back to the dealership for warranty repair.
After that it was a constant search for a way to keep the engine from overheating. It was okey in town and on the highway unloaded but in the mountains pulling a trailer it would over heat. Things done to attempt a cure for the overheat were to remove the tunnel pan and go to expanded metal grate; move the A/C condensor up on top of the roof; go to a 7 blade fan; add a better radiator shroud; go to a 3 row radiator; and finally add a water invection system ahead of the radiator. In the end it worked quite satisfacorily. I think one of the problems was the tight shrouding of the engine by the covers which did not allow air from the radiator a place to exit except down in front of the engine.
One thing to consider is that this was the 318 LA engine that was designed for smog reduction. The distributor was timed for 4 degrees After Top Dead Center at curb idle. At about 1000 RPM the timing advanced to 6 degrees BTDC after which the regular advance continued. The distributor had a vacuum advance designed as cruise economizer so it was not become involved in hard pulling. If you had an ear for it you could hear the engine pinging under hard load. At a late date we installed a manifold pressure gauge (vacuum gauge) that allowed the driver to gauge when the engine was overloaded and thus to slow down or shift down.
The only other chronic problems we had with this van was need of constatnt attention to the U-joints. Even with regular lubrication the U-joints would start squeeking and need replacement. Also the alternator seemed to need feplacement often. It is placed down low on the right side next to the side cover.
I have a 1989 Dodge B250 extended camper van with a heavy fiiberglass top…all pulled by a 318 engine. Have not had any overheating problems. i suspect Rod Knox is correct that you have a circulation problem and should try replacing the water pump.