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Discussion Starter · #1 ·
so after 8 yrs I decided it was time to go ressurect my 84 and have developed an overheating issue

heres what I can check off

radiator clean. No rats nest behind it

radiator has been flushed twice as has whole cooling system

new water pump (correct pump as well)

new hoses upper and lower

180 degree failsafe thermostat

fan works as it should

radiator cap is new

at idle from start car runs between 180 then comes up to 200 and will stay they at idle for 10 to 15min unchanged. That said if I drive it after a few miles it come up to 220 then 225 and slowly starts creeping up to 235 to 240. Driving 55mph does not lower it and when I go to parked the fan does not touch it either.

I originally was thinking this was the notorious rats nest scenario but the radiator is clean on both sides and unobstructed and I have pulled it and checked for build up between the fins. its clean. Radiator was a new oem unit installed shortly before I parked the car. System was filled with distilled water.

Motor is modified. 30 over. flat tops, .488 /.488 lift cam 106/110 lsa. dart heads. normal operating temp was around 200 to 205

Temp isnt shooting right up it will idle in the drive and maintain proper temp but when driven it starts creeping up
 

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so after 8 yrs I decided it was time to go ressurect my 84 and have developed an overheating issue

heres what I can check off

radiator clean. No rats nest behind it

radiator has been flushed twice as has whole cooling system

new water pump (correct pump as well)

new hoses upper and lower

180 degree failsafe thermostat

fan works as it should

radiator cap is new

at idle from start car runs between 180 then comes up to 200 and will stay they at idle for 10 to 15min unchanged. That said if I drive it after a few miles it come up to 220 then 225 and slowly starts creeping up to 235 to 240. Driving 55mph does not lower it and when I go to parked the fan does not touch it either.

I originally was thinking this was the notorious rats nest scenario but the radiator is clean on both sides and unobstructed and I have pulled it and checked for build up between the fins. its clean. Radiator was a new oem unit installed shortly before I parked the car. System was filled with distilled water.

Motor is modified. 30 over. flat tops, .488 /.488 lift cam 106/110 lsa. dart heads. normal operating temp was around 200 to 205

Temp isnt shooting right up it will idle in the drive and maintain proper temp but when driven it starts creeping up
Air in the system , put the front wheels up on ramps to get the cap higher than the thermostat and check level
 

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Discussion Starter · #7 ·
unfortunately been there done that same results. Pulling the heads off going to disassemble them clean and magnaflux them to check for cracks and obstructions. Im thinking its either a slightly blown head gasket, obstruction or a crack. No big deal for me really just time as I do the majority of work myself will just have to pay $10 a head for the magnaflux check pretty much the only thing I cant do at home Im a retired toolmaker and have my own homeshop and can do most of it like valve grind. seat grind at home
 

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sounds like the water pump impellers defective, why not just replace the water pump and see if that helps
be aware there are standard and reverse rotation and long and short water pumps, for both bbc and sbc. anything but the correct pump will cause heat issues

 
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