[55Willys]

Yup new guy here. Yup made my introduction in the other forum already. So here's my issue...

I have a 55 Willys Wagon that idles at 190 degrees pretty much all day but when the RPMs get above 2k it will run 230+ regardless of vehicle speed. It will go from 230+ down to 190ish in about 45 seconds when the RPMs go back to idle. Casting numbers say it's a 1979 305. Other than an Edelbrock intake and carb it's stock. Radiator is a 4 row with a core about 16X24 and has been flushed and flow tested. Has a 190 T stat that is in correctly and functions(I've tried a different t stat with no effect no 1/8" hole drilled) I have also installed and electric fan as the mechanical fan sat too low to line up with the radiatorCenter line of fan is about 8" lower than the center of the radiator). I've tried 2 different water pumps and I think this is where I'm running into problems. Both have pushed hot coolant out of the block into the bottom of the radiator. The top radiator hose is cold and the bottom hose is hot. I have a short style water pump from a 63-67 Corvette that is supposed to be standard rotation. The pump looks identical to the pump show in post #6 of the "mild 355 overheating" thread. I run V belts and the pump spins CW. I even went so far as to fill the kitchen sink with water, hook an electric drill to the shaft and spin it CW. It drew water in through the lower raditaor hose port and pushed it out like it would push into the block. But when I put it on the engine the bottom hose gets hot and starts to fill the radiator with hot coolant as soon as the T stat opens.

Now I'm willing to admit I'm likely an idiot and this is an overly simple fix. So let the flaming and heckling begin. All I ask is that if you could possibly help me fix this issue while you have your fun please do. Thanks for the help...let the fun begin....

 

[heyjude076]

.... I've tried 2 different water pumps and I think this is where I'm running into problems. Both have pushed hot coolant out of the block into the bottom of the radiator. .....

I run V belts and the pump spins CW. I even went so far as to fill the kitchen sink with water, hook an electric drill to the shaft and spin it CW. It drew water in through the lower raditaor hose port and pushed it out like it would push into the block. But when I put it on the engine the bottom hose gets hot and starts to fill the radiator with hot coolant as soon as the T stat opens.

....

These two statements contradict each other. The first statement the pump pushes the water out of bottom and the second the pump draws the water.

Are you sure which way the pump is turning while the engine is running? Are you sure the pump is deigned to turn in that direction? There are pumps for each direction of rotation. In both tests are you looking at the face of the pump to determine the direction?

Can you look into the top of the radiator (cap off) and determine the water flow? If as you say the pump is pushing water into the bottom of the radiator then the rad is filling from the bottom up and should overflow from the cap.

 

[55Willys]

Yes I realize these statements conflict each other. Either I had the drill set to run counter clockwise and didn't notice(possible)or the enigine is spinning counter clockwise(not possible) or there is something odd going on inside the engine maybe?

Everyone that I've talked to and all that I have read on line confirms that I have a standard rotation pump(pump turns clockwise). Pump hooked to drill turned clockwise in the sink confirms this(draws water in through hose opening). Yup was looking at the front of the pump both times. With rad cap off coolant does over flow the radiator.

 

[ericnova72]

Are you running a vacuum advance set-up on your ignition??

 

[55Willys]

Yup sure am.

 

[dinger]

You may be running the water too quickly through the block. When the RPM's go up, the speed of the pump does also, if the water is running through the block too quickly it will not cool efficiently, the water will not be absorbing the heat as well as it should be, you may be over-cooling. If the pump is a high volume pump you may have to change or restrict the water flow into engine. I don't know if running a higher temp thermostat will help, some here will know this though. AND I may entirely wrong with my diagnosis...I have seen this happen though. Good luck. :thumbup: