1970 cutlass supreme overheating with electric fans and aluminum radiator
April 22nd, 2024, 08:40 PM
#1
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1970 cutlass supreme overheating with electric fans and aluminum radiator
1970 Oldsmobile cutlass is overheating I install electric fans and aluminum radiator. I have a 160 thermostat also have a 195/210 top and bottom is getting hard at idle after 10 to 15 minutesof car running Can pull radiator cap off coolant is flowing through radiator. Water is going through holes as soon as thermostat opens up within 5 to 6 minute both hoses get hard can't seem to figure out the problem not too sure if it's the water pump bad or blockage motor in any ideas
April 22nd, 2024, 08:44 PM
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1970 Oldsmobile cutlass is overheating I install electric fans and aluminum radiator. I have a 160 thermostat also have a 195/210 top and bottom is getting hard at idle after 10 to 15 minutesof car running Can pull radiator cap off coolant is flowing through radiator. Water is going through holes as soon as thermostat opens up within 5 to 6 minute both hoses get hard can't seem to figure out the problem not too sure if it's the water pump bad or blockage motor in any ideas
April 23rd, 2024, 05:44 AM
#4
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The water pump won't cause overheating (despite the fact that it's the first thing everyone wants to replace). Unless the impeller has sheared off the shaft (and you're more likely to win the lottery), if the pump is turning, coolant is circulating.
At the risk of repeating myself, these cars didn't overheat when they left the factory with a mechanical fan and copper radiator. How about starting by telling us exactly what else has been done to the motor? Many overheating problems are not cooling system problems. Incorrect vacuum advance and lean mixture can also cause overheating. Are all the seals in place between the radiator and core support? And a 19" mechanical clutch fan will move more air than electrics.
At the risk of repeating myself, these cars didn't overheat when they left the factory with a mechanical fan and copper radiator. How about starting by telling us exactly what else has been done to the motor? Many overheating problems are not cooling system problems. Incorrect vacuum advance and lean mixture can also cause overheating. Are all the seals in place between the radiator and core support? And a 19" mechanical clutch fan will move more air than electrics.
April 23rd, 2024, 06:20 AM
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Stupid question, if you can take the radiator cap off after running and coolant is not boiling over are you sure it is overheating ? what to do you mean by 195 & 210 top and bottom, , do you have a hand held infrared thermostat ? My thought is to get yourself a thermostat that goes into the radiator coolant and see what that reads as to your gauge.. gauges can be off,,If the water-pump propeller fell off it would over heat real fast & keep climbing... good luck !
Last edited by zl1 camaro; April 23rd, 2024 at 06:33 AM.
April 23rd, 2024, 06:23 AM
#6
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I ***-U-ME he is talking about removing the cap right after starting a cold engine to see the flow. I've done that also. If you leave it off, it will boil over.
April 23rd, 2024, 06:30 AM
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April 23rd, 2024, 06:36 AM
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The water pump won't cause overheating (despite the fact that it's the first thing everyone wants to replace). Unless the impeller has sheared off the shaft (and you're more likely to win the lottery), if the pump is turning, coolant is circulating.
At the risk of repeating myself, these cars didn't overheat when they left the factory with a mechanical fan and copper radiator. How about starting by telling us exactly what else has been done to the motor? Many overheating problems are not cooling system problems. Incorrect vacuum advance and lean mixture can also cause overheating. Are all the seals in place between the radiator and core support? And a 19" mechanical clutch fan will move more air than electrics.
At the risk of repeating myself, these cars didn't overheat when they left the factory with a mechanical fan and copper radiator. How about starting by telling us exactly what else has been done to the motor? Many overheating problems are not cooling system problems. Incorrect vacuum advance and lean mixture can also cause overheating. Are all the seals in place between the radiator and core support? And a 19" mechanical clutch fan will move more air than electrics.
April 23rd, 2024, 06:45 AM
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if the 19 inch mechanical fan pulled and threw more air than electric fans why would newer vehicles come with electric fans that run at a higher temperatures and cools off extremely better just wanted a modern twist for classic so it runs cooler and has more throttle responsible heat plays a major part totally understand what you're saying but if the mechanical fans were that good, they would've never opted out to electric fans on vehicles that produce more power from factory
April 23rd, 2024, 07:27 AM
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and you are 100% correct fans do not run all the time exactly how my fans run in the 1970 cutlass supreme. My fans only kick on at 210 and turn off at 195 which I feel that the temperature sensor is pretty high so I'm gonna change it to it 175 to a 185 meaning it kicks on at 185 and turns off at 175 I'm running at 160 thermostat
April 23rd, 2024, 08:03 AM
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YOU mean belt driven fans would be impossible to use with transverse mounted engines ? all transverse mounted engines require electric fans..
April 23rd, 2024, 08:21 AM
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if the 19 inch mechanical fan pulled and threw more air than electric fans why would newer vehicles come with electric fans that run at a higher temperatures and cools off extremely better just wanted a modern twist for classic so it runs cooler and has more throttle responsible heat plays a major part totally understand what you're saying but if the mechanical fans were that good, they would've never opted out to electric fans on vehicles that produce more power from factory
April 23rd, 2024, 09:29 AM
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April 23rd, 2024, 09:44 AM
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April 23rd, 2024, 10:04 AM
#18
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Other thoughts:
Honestly, I don't see a problem here. 210°F on the outlet from the engine(bottom hose) is fine.
210°F is not high.
195-210° is the optimal range for this vintage engine. 160-185° is too cold for an IC engine to run efficiently. 220-230 would be in the yellow...235°-and up is too hot.
Hard hoses at idle are normal at full operating temp & system pressure. The pressure is there for a reason, to increase the boiling point.
What PSI is the cap? Verify it is popping off at the rated PSI (with a pressure tester). You can run a lighter cap. Stationary gen-sets run 8PSI. I don't recommend that low but 12-14PSI is fine if you are losing sleep over the stiff hoses.
Honestly, I don't see a problem here. 210°F on the outlet from the engine(bottom hose) is fine.
210°F is not high.
195-210° is the optimal range for this vintage engine. 160-185° is too cold for an IC engine to run efficiently. 220-230 would be in the yellow...235°-and up is too hot.
Hard hoses at idle are normal at full operating temp & system pressure. The pressure is there for a reason, to increase the boiling point.
What PSI is the cap? Verify it is popping off at the rated PSI (with a pressure tester). You can run a lighter cap. Stationary gen-sets run 8PSI. I don't recommend that low but 12-14PSI is fine if you are losing sleep over the stiff hoses.
April 23rd, 2024, 01:37 PM
#19
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if the 19 inch mechanical fan pulled and threw more air than electric fans why would newer vehicles come with electric fans that run at a higher temperatures and cools off extremely better just wanted a modern twist for classic so it runs cooler and has more throttle responsible heat plays a major part totally understand what you're saying but if the mechanical fans were that good, they would've never opted out to electric fans on vehicles that produce more power from factory
Mechanical rams are kinda noisy when they are engaged. I’m sure the NVH engineers hated them.
The engine will warm up faster with the fans off. That’s important for meeting ever more restrictive emissions standards.
Electric fans are ever so slightly more efficient from a fuel economy perspective.
Having said all that, it’s hard to beat a good thermal fan clutch with an engine driven fan. If electric fans were more efficient, big trucks would use them.
My 06 diesel truck has the best of both worlds, it’s got a mechanical fan with an electric clutch. The fan does nothing until the pcm commands the fan on. There is no questioning when that happens!!
April 23rd, 2024, 01:40 PM
#20
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Elevate the front of the car. Remove the radiator cap, top off the cooling system. Leave the cap off and the front raised up. Gravity will naturally force coolant down, and push any air out. The next morning, slowly top off the radiator, reinstall the cap and lower the car. Problem solved.
Work smarter, not harder!!
April 23rd, 2024, 03:24 PM
#21
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Radiators without a coolant recovery system on it do not get filled to the very top, thee must be room for expansion. If you fill the radiator to the top, it will always push coolant onto the ground or into the catch can as the car warms up. This is not overheating.
April 23rd, 2024, 03:35 PM
#22
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Good point.
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