still HOT
Thread Starter
Pro
Joined: Jan 2003
Posts: 528
Likes: 5
From: Templeton Ca
still HOT
Well - I couldnt get an IR gun to check the temp but it's running HOT enough to boil out the overflow tube when I shut it off .
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
Melting Slicks
Joined: Jan 2005
Posts: 3,022
Likes: 94
From: Texas
..did you get a "new" radiator cap also?
...checkfunction of new fan clutch. I've seen a couple that we're defective when new.
...slow timing will make one overheat quickly. Make sure the harmonic balancer timing mark is accurate. Outside of the balancer could have slipped on the hub.
Do you have an aluminum or copper radiator?
...checkfunction of new fan clutch. I've seen a couple that we're defective when new.
...slow timing will make one overheat quickly. Make sure the harmonic balancer timing mark is accurate. Outside of the balancer could have slipped on the hub.
Do you have an aluminum or copper radiator?
Drifting
Joined: Jun 2005
Posts: 1,974
Likes: 2
From: Crownsville Md.
My car also ran hot. Did you fill the radiator to the top? I found that my car also puked coolant to a certain level then it would stop. It seemed to find it's own level of coolant needed.
Shemp
Shemp
Le Mans Master
Joined: Nov 2008
Posts: 5,691
Likes: 12
From: columbus oh
Well - I couldnt get an IR gun to check the temp but it's running HOT enough to boil out the overflow tube when I shut it off .
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
CF Community Team
Joined: Oct 2004
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Likes: 5,249
From: Cape Cod, Mass.
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Flushing out an old radiator that had a leak is a red flag to me. Look into a Dewitt's aluminum radiator and your problem may be solved.
Burning Brakes
Joined: Dec 2006
Posts: 768
Likes: 1
From: Round Rock Texas
Make sure your using a "correct" GM fan clutch, not just a replacement from your auto parts store. They are expensive but solved my overheating problem. Also make sure your seals are installed on the fan shroud. LOTS of posts about overheating...do a search and start reading and you will find tons of info.
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Melting Slicks
Joined: Jul 2004
Posts: 2,869
Likes: 196
From: Maryland
You still need to ascertain the actual temperature. If you have a kitchen meat thermometer you could tape the probe to the underside of the upper hose. As Shemp says you could have overfill the system and its just finding its level. If the temp is accurate then I would suspect the radiator especially if its original or copper. Also are you running a correct and functioning VAC?
Race Director
Joined: Apr 2005
Posts: 11,284
Likes: 2,146
From: Bowling Green, Kentucky
I would check both inlet and outlet temperatures at idle and at around 2000 RPM. Also make certain all radiator and shroud seals are in place.
Do you overheat at idle only or while driving??
You can also install pieces for factory AC car to help in cooling, especially at idle.
Radiator caps can be checked at various parts stores and shops, but if radiator hose feels solid when warm/hot, cap is probably ok.
Use 180 F thermostat, and check operation before installing (using hot water).
Larry
Burning Brakes
Joined: Jan 2005
Posts: 768
Likes: 0
From: Leavenworth Washington
I would check both inlet and outlet temperatures at idle and at around 2000 RPM. Also make certain all radiator and shroud seals are in place.
Do you overheat at idle only or while driving??
You can also install pieces for factory AC car to help in cooling, especially at idle.
Radiator caps can be checked at various parts stores and shops, but if radiator hose feels solid when warm/hot, cap is probably ok.
Use 180 F thermostat, and check operation before installing (using hot water).
Larry
That's my 2 cents.
Geek
Pro
Joined: Feb 1999
Posts: 735
Likes: 174
From: Myrtle Beach South Carolina
Well - I couldnt get an IR gun to check the temp but it's running HOT enough to boil out the overflow tube when I shut it off .
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
327/300 just rebuilt by reputable shop
I redid the timing and it's running GREAT at 10*
The fan clutch is new
The water pump is freshly rebuilt
The radiator was just flushed out when a leak was plugged/welded
The shroud is in great shape .
plenty of coolant .
I'm going nuts trying figure this out ! I've still got some time before I take it to a car show in Las Vegas June 4th,5th and 6th. I'm gonna trailer it there but would really like to be able to drive it around some
Safety Car
Joined: Nov 2001
Posts: 4,424
Likes: 619
From: northern CA
I had this same problem in my 327-300hp, too, after a rebuild. Before the engine was rebuilt the original radiator had just enough cooling margin to keep the engine from overheating. Overheating was kept in check so long as airflow was moving through the radiator. Not more than a few minutes of engine idling got the temp gauge moving fairly quickly to the right.
After the engine rebuild there was no way to keep the engine from overheating. A newly rebuilt engine will run hotter as it wears in. A new Harrison aluminum radiator replaced the old one. No overheating problems after that.
Aluminum radiators (stacked plate) can be flushed out but it likely won't be enough to remove built up scale that forms in the tube runners. These radiators can't be rodded out.
Years later the replacement Harrison radiator eventually developed a leak....................and the overheating problem was back, also. This radiator too, was now worn out. Once a leak develops, the radiator is likely toast. Other leaks are likely to spring.
A new DeWitt's replaced that Harrison.
Pro
Joined: May 2010
Posts: 560
Likes: 2
From: North Las Vegas Nevada
Did they replace the temp sending unit as part of the rebuild? Not sure if C2's have the same issue but an over-the-counter sending unit will not work properly in a C1 - wrong resistance values and it just pegs out.
I'd also be tempted to throw in a few more degrees of advance and see if things improve.
DT
I'd also be tempted to throw in a few more degrees of advance and see if things improve.
DT
Pro
Joined: May 2010
Posts: 560
Likes: 2
From: North Las Vegas Nevada
DT
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
If the center hub/spider arms are on the engine side (vs. the radiator side) of the fan blades, the fan is installed correctly.
We still don't know what you have for a radiator.
We still don't know what your ACTUAL coolant temperature is.
We still don't know if your vacuum advance can is working, how much advance it's adding at idle, and whether it's connected to a full manifold vacuum source.
If you "fill" the expansion tank, it'll puke coolant on the ground. You fill the tank to the HALF-FULL mark with the coolant COLD; if you don't leave room for the coolant to expand, it expands on the ground.
We still don't know what you have for a radiator.
We still don't know what your ACTUAL coolant temperature is.
We still don't know if your vacuum advance can is working, how much advance it's adding at idle, and whether it's connected to a full manifold vacuum source.
If you "fill" the expansion tank, it'll puke coolant on the ground. You fill the tank to the HALF-FULL mark with the coolant COLD; if you don't leave room for the coolant to expand, it expands on the ground.
Last edited by JohnZ; May 20, 2010 at 08:12 PM.
Thread Starter
Pro
Joined: Jan 2003
Posts: 528
Likes: 5
From: Templeton Ca
hot
I have an aftermarket radiator with no marking that I can find . It's not an original that's for sure .
Coolant temp is unknown except the guage reads around 225-230 . I still dont have an IR gun .
coolant level is 1/2 of the tank when cold .
removed the thermostat today and it ran up steadly to 215* in about 30 min .
Had to go to work and left the car in that condition .
maybe a kitchen thermo will give me a better idea of how hot it's really getting .
guess I'll have to learn more about VAC'S so I can answer your questions about it .
Coolant temp is unknown except the guage reads around 225-230 . I still dont have an IR gun .
coolant level is 1/2 of the tank when cold .
removed the thermostat today and it ran up steadly to 215* in about 30 min .
Had to go to work and left the car in that condition .
maybe a kitchen thermo will give me a better idea of how hot it's really getting .
guess I'll have to learn more about VAC'S so I can answer your questions about it .
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
If you have a kitchen thermo, drop the removed thermostat in a pot of water and start to heat up. Watch the thermostat and see when/if it opens, fully, and at what temp....
RK
Last edited by RoadKing96; May 21, 2010 at 06:23 AM.