1991 vanagon overheating

[AZ Landshaper]

This clearly not a solution to rely upon. If you lend the vehicle ( ) to anyone, they run the risk of cooking the engine?
You need to keep on the automated fan option. This thing with the switches is risky business.
Have you tested the thermo switch using a multimeter?
Have you moved through the system finally ending up at the fan?

Seems as though it would require more work to set up a switch than strategically testing the entire radiator cooling design. Isnt there a relay involved? Ive heard those are close to bulletproof but maybe not.
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85 Weekender w/ EJ22
Previously
64, 71, 72, 73, 76, 81, 84, 85 & 87 Campmobiles and Westfalias
and a 67 bug.

[jimf909]

[Burr85]

My worry is that the fans never come on by them selves . And my gauge is right at the top with red light blinking . At this point I used a laser gun to see the temp and at the right side top of the radiator above the thermoswitch it is at 199-200 Fahrenheit and at the thermoswitch is is at 150-175 and I worry about risking an overheat or head gasket.

[Burr85]

So far I have replaced the thermoswitch with a 185-193 degree one and a new resistor as it was bad when I tested it. Now if I jump the terminate at the thermoswitch all speeds work. But now no fan speed will come on by itself well besides when I turn on the a/c. So I tapped into the wires at the plug of the thermoswitch and hooked up a manual switch in the van so I can turn on low or high speed manually. Witch works with low or high. But when the gauge gets to 3/4-7/8 I have to turn the manual switch on then immediately off and the fan will stay on until it doesn’t need it and turns off by itself. And when I turn the switch on then off immediately I usally switch low speed but the van does highspeed until it turns off by it self . And I have done the click test and power and resistance test to both low speed and high speed relays I’m just confused why doesn’t it kick on by it self and never a low speed even though it works while jumping it.

[Wildthings]

[AZ Landshaper]

Do you have a blockage in the rad?
with the top at 199 and the bottom at 170 I think there is a problem. Im going to look back at the route.

https://www.flickr.com/photos/14602120@N03/3114668260/

So given this route shouldnt your radiator be hot near the thermo and cooler elsewhere? Are your hoses routed correctly?

The temps sound correct but not for the locations you describe.
_________________
Support Small Business.

-------------------------------------------------------
85 Weekender w/ EJ22
Previously
64, 71, 72, 73, 76, 81, 84, 85 & 87 Campmobiles and Westfalias
and a 67 bug.

[Burr85]

I doubt it I just replaced the radiator as the old one was clogged. Now the cooling system is all new besides the exspansion tank. Maybe because it has SS hoses? I am going to try the lower temp switch

[Wildthings]

Sure you have the two radiator hoses on correctly? If switched you could have an airlock in the radiator that would be hard to eliminate.

[crazyvwvanman]

I would make sure there is zero air in the radiator and make sure the radiator is getting warm at the bottom way before it gets just as warm at the top.

I'd replace the temp switch with a new Behr or Wahler stock one for 2.1 vans. The current switch sounds like it isn't working right.

Why is the fan apparently running via the temp switch but only after you first start it manually? Odd behavior. If the switch is hot enough for high speed it should have first come on low speed. Once high speed cools things enough the fan switch should switch to low speed until even that isn't needed. Hope you figure it out.


Mark

[Burr85]

Thank you everyone I have got the westy cooling as it should fans come on and off by them selves. Installing the new thermoswitch Wildthings suggested worked like a charm and radiator heats up bottom to top and all is great . Thanks everyone now my family can enjoy without that worry.