Question on the cooling system...

[muleskinner]

I have replaced everything I know to replace. The fan, switch in the thermostat housing, thermostat, and now the relay ... with a used one.

The problem I was having was the fan was staying on all the time. I replaced the relay and now it stays off. I tested it by disconnecting the switch and the fan came on. So I plugged it in and ran the car & the temp. gauge got to 3/4 and the fan would not come on. Rad fluid started coming out of the reservoir so I stopped the motor.
My question is how far high does the temp gauge get before the fan comes on? I didn't want to blow a head gasket.
Also is there another part I might need to replace?

Thanks in advance
Mike

[bravekozak]

I have replaced everything I know to replace. Also is there another part I might need to replace?

It says the temperature on the fan wiring diagram.

Check the grounding of the coolant temperature switch.
I trust you did not use any teflon tape.

[Movin]

Using the stock gauge my fan comes on about one needle past center on my auto, my 4 speed and my 5 speed but if the cooling system has a lot of build up the coolant gets hotter before the switch does. All of these are stock except the good metal radiator started leaking a couple years ago, now they all have plastic tanks. The ignition switch went bad in my red one and I put an Aspire rad in to get out of the mountains from camp. Towing a heavy trailer it never got warm enough to run the fan. Even with the lower hose in a pretzel to make it under the hood. Heck the hood won't even fit over that thing. Going to get one of the chinese metal ones if anyone recommends one.

[bravekozak]

The thin tubes between the upper and lower brass reservoirs are made out of steel instead of brass. The steel will slowly rust and spring a leak which is exactly why it was designed that way. I was at a rad rebuilder and saw how it was resoldered. I asked why the tubes weren't brass. Patent.

[muleskinner]

It says the temperature on the fan wiring diagram.

Check the grounding of the coolant temperature switch.
I trust you did not use any teflon tape.

I replaced the temperature switch (that's in the thermostat housing).
No, I didn't use Teflon tape.

[muleskinner]

if the cooling system has a lot of build up the coolant gets hotter before the switch does. .

So I may have to flush out the cooling system to make it work properly?

[Movin]

You just replaced the switch, it should be exposed to fresh coolant to turn the fan on at the right temp. If there is a coating on the rest of the cooling system you may not be conducting heat out of the metal as well, in other words the combustion chamber can be hotter than normal with normal water temp. Not the problem you are chasing. If you unplug that switch does the fan turn on ?

[muleskinner]

If you unplug that switch does the fan turn on ?

Yes.

[Movin]

Idle after your next return home and watch the gauge. Feel the upper hose it should start to get tight as the pressure comes up. It should be uncomfortable to touch for very long but okay for a moment. The gauge should be up to a half . A little bit more and the fan should kick on.

If the overflow starts working before the hose gets tight and the gauge is up then the cap is not able to seal the radiator neck. The surface in the bottom of the neck might be rough or uneven.

[muleskinner]

Idle after your next return home and watch the gauge. Feel the upper hose it should start to get tight as the pressure comes up. It should be uncomfortable to touch for very long but okay for a moment. The gauge should be up to a half . A little bit more and the fan should kick on.

If the overflow starts working before the hose gets tight and the gauge is up then the cap is not able to seal the radiator neck. The surface in the bottom of the neck might be rough or uneven.

Cap is rough on the bottom. I would say that is it. Unfortunately my fiancés son who drives the festy was forced off the road today by someone coming the other way and slammed the side of the festy in a pole & snapped the pole in half. Thank goodness he's ok but the festy is totaled. He is so depressed that the festy is totaled. Now he has no ride. I will post pictures in another thread....

[Movin]

I can't believe how strong the body shell is, Having a festy lover okay is most important, He can start over with another car.