Heater shutoff valves and overheating...

moosoMember

I installed a new aluminum lay down radiator and a couple of heater shutoff valves.
Everything has worked fine but on two occasions when the outside temperature was near 90, I have experienced overheating. Yesterday, it blew past the pressure cap on the expansion tank and just kept boiling...big time.
I either did something wrong with those shutoff valves, or I hooked up the radiator backwards. Or...something else?
The temp guage never read over about 165.
The two hoses going through the firewall are AC hoses so I left them alone. The two coolant hoses that go down under the tunnel are the ones I put the shutoff valves in. Was this wrong?
I'm sure I got the radiator installed right, but my car didn't have a vent/overflow tube from the radiator back to the expansion tank. There is no place to attach it to the expansion tank and I was told it wasn't necessary, but it was a good idea to have it. What do you think?
I think that some temp guages were hooked up at the expansion tank. Mine doesn't seem to be this way. I think the sensor is somewhere else in the system. What is the best way to get an accurate temp reading. Something is fishy here.
My new puller fans are working properly, so it is not that I don't have air flow.
Sheesh...I had less problem with the stock set-up! Haaalp!
Mooso.

6/2/056:17 AM

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roverltdMember

Could be air bubbles in the system. Looks at other posts on filling radiators. Jacking up the rear of the car so trapped air is drawn back. There is a tool from lesile that everyone seems to like that allows coolant to backfull once air is relieved. In draining the coolant system you create many chances to create trapped air. Also keep the heater shutoffs open for a few days to make sure that any trapped air is also relieved from the heater coil.

6/2/058:34 AM

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fordgtMember

It's actually a LISLE funnel here is a previous post
Try these guys, I got mine for 28 including shipping. toolcraze.com and I got it in 2 days. Their # is (818) 702-6777 and their product code is L2SRFK The cost was less than 19 but they sock on about 9.50 shipping for UPS ground.
Basically, you jack up the rear of the car about 12" and fill the funnel with coolant solution and run the car until it reaches operating temperature and then let it run for awhile occasionally "goosing" it a little. The key is to keep the funnel full. They even include a stopper so that you can remove the funnel without spilling all over your engine compartment.
Good Luck
Gary #06984

6/2/0510:49 AM

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moosoMember

Thanks guys. I got out the manual and confirmed that my radiator hoses are correct. I also found that as late as '73, there was not a vent hose from the radiator bleeder to the supply tank, so I assume this is not critical.
I found that what I was refering to as the "expansion tank" is actually the supply tank and that what I thought of as the "overflow tank" is the expansion tank. Sorry for the confusion of terms in my first post.
When I refilled the system after installing the radiator, I had the heater hoses open, the heater control open, and I unhooked the heater hose from the water pump. Then I filled the system until the coolant flowed out of the water pump. Reinstalled the hose and continued filling until the bleeder on the radiator stopped releasing air. Over the next few days I checked the bleeder before start up and refilled the supply tank as necessary. After a few days of this, the coolant stayed filled to the top in the supply tank and the bleeder flowed only water...no air bubbles.
Man, I thought I had it then! After this last boil over, I can only conclude that you're right, there is still air in the system. I'll try it all again. I'll see about getting that funnel. Heck, I'll try anything!
Thanks, Mooso.

6/2/051:17 PM

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