Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
I have 454ci big block Chevy overheating. Tried new pump, timing, 3 row aluminum radiator, electric fan pulling 3300cfm of air. Can’t figure out the issue. Keeps climbing past the setting of the thermostat, which is 180. This is for my personal vehicle. 1986 Buick Regal, weekend car. Thanks for any help. By the way any recommendations on a racing shop near me, Brooksville and Spring Hill area of Florida. Thanks
Tyler, it’s gone over 200 degrees if I don’t shut it off.
I have not checked both hoses. Thanks for that one. I will follow up.
It keeps getting hot at lights and while driving.
Keep asking questions Tyler because I’m at my witts end. I’m not enjoying my car. If I cannot figure out this problem then I have no choice but to put another motor that I have in my garage a small block Chevy 355
I watched someone using a laser thermometer on all the coolant hoses, I started doing the same and found one of my hoses to the throttle body was 60 degree F cooler, so I know thats partially blocked or something, the fast idle valve outlet.
Id check all the hoses like the heater matrix ones. My car was getting hot, the clip around the lower radiator hose was pressing against my subframe, so it was a slight leak, but it was enough to lose half my coolant
The engine looks great, I know what its like when you have the temperatures going over, its difficult to enjoy the new engine, as you have to go short distances till you find out whats wrong
Thanks Crombie. I will check the hoses to see if any one of them are cold as suggested. But if I can’t figure it out, then I’m going to replace it with my small block Chevy. Stress stress stress. You know the deal.
Have you got the by-pass plumbing for the heater connected up ? The by-pass flow is needed for the thermostat to work.
One trick that works with special build cooling systems is to drill a couple of 1/8" holes in the thermostat valve plate to allow some coolant flow around the thermostat.
A common cause of overheating at idle speed in the old days of distributer ignitions was the ignition timing to much retarded .
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Last edit: 6 years 10 months ago by Andy.MacFadyen.
I checked the timing and is at 12 degrees btdc.
The bypass cooling, I don’t have any cooling hoses to the water pump except the upper and lower hoses Andy. Can you send me a picture of that bypass hookup. Can’t picture it in my mind.
Bypass hose is just the 5/8" borevhose that normally goes to the heater all the that is needed is a hose from the engine side of the thermostat back to either the water pump or T into the lower hose, it lets coolant circulate through the cylinder block past the thermostat back to the water pump when the thermostat is closed.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
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