I have a 1972 Buick Skylark with a stock 350 2 barrel. It starts up and runs good at around 200-210 degrees except that when I shut the car off the temperature climbs up to 240-250 and often leaks out of the overflow tank. I was told to get a new heater core, but the old one isn't leaking so I'm not sure what the problem is. I was thinking thermostat or water pump ? ? ? Thanks for any help . ..
200-210.....way to hot....you should run 180-190. Get a 4 core rad, 7 blade fan w/thermostatic fan clutch. Make sure your timing is right and you are not running lean. Torqflo 922797 from Autozone for $44 is a great thermostatic clutch.
I just had to return this fan clutch this morning because it doesn't fit. The snout on my water pump is too long for the cavity in this fan clutch. Oh and by the way it was 62.99 at AutoZone not 44.00. Any thoughts?? I bought one at Napa but car doesn't run much if at all cooler with that one and a 7 blade fan upgrade... Ron
This seems to be a problem on new water pumps...the snout is way too long. Anyways, since you installed a new clutch and fan, your problem is your radiator....get a 4 core.
Do you have A/C.....disconnect the belt from the A/C compressor. Whoa La.......Temp back down to 180-190F. My A/C never did work right! Gotta Love It!
Does it run hot on the hiway or in town or both? If your problem just started, change your thermostate or run without out it to see if it makes a difference, it could be sticking part way open and not allowing full flow, if it runs cooler without, buy a new one. Also, your fan needs a shroud, your car should have one, but just make sure its intact. Do you have bubbles happening in the Rad when the engines running? my 2 bits, Gord
Something to consider here is that, when the engine is off, no coolant flows into the radiator. The radiator dissipates the heat that is collected in the engine, and PUMPED into it. In other words, with the engine off, the coolant temp will rise as the heat collected has no exit. This temp rise is normal, especially with high underhood temps from A/C and hot weather. If, during low speed operation, the temp rises above 210, there is an issue, likely with raidator size or air flow. The temperature ise is typically not seen, as, with the key off, the temp gauge drops off to the left. Having used mechanical gauges frequently, I have seen this rise in EVERY application. The radiator has no effect on the engine temp unless the coolant is being pumped through it. Ray
