74 Cooling Issues
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Joined: Jul 2018
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74 Cooling Issues
Guys new C3 Owner here and new to the forum. Not a complete newby to forums as a member of Stovebolt Chev trucks and Ford N tractors, but nevertheless I will probably unintentionally violate a few formal and informal rules here. First violation, not searching the forum for immense discussion of the same issue before as if you're the first person to have the issue. I did a search, and found the discussion on electric fans and a few tangents but not exactly my issue. Here's my deal. 74 original 350 has been bored/stroked to 383 with aluminum heads, headers and new intake by prior owner. Appears fan shroud has been cut in 1/2 during the motor rebuild, so the fan (w/clutch) is about 1/2" behind the shroud. None of the fan is within the shroud. I AM NOT A NUMBERS MATCHING GUY ! Live in S. Texas with too many days of 100 deg weather. Took my new 74 on a 50 mile stroll yesterday, she ran fine at 200 deg until I sat idling while fiddling with my GPS,then temps started climbing. Instantly cooled back down once underway and air moving through the radiator. Has factory air BTW. I would prefer not to add electric fans, but cannot have a vehicle that runs hot in my climate. How would you guys proceed?
Last edited by dalane; Jul 14, 2018 at 08:15 PM.
Team Owner
Joined: Jun 2000
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From: Southbound
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Le Mans Master
Joined: Aug 2017
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From: Cool Northern Michigan
Unofficial Quotes:
A few degrees in timing will change a few degrees in temps.
Overheating at idle is a "air" circulation issue.
Overheating at speed is a "water" circulation issue.
With the fan outside of the shroud you are only getting 50-75% efficiency.
A few degrees in timing will change a few degrees in temps.
Overheating at idle is a "air" circulation issue.
Overheating at speed is a "water" circulation issue.
With the fan outside of the shroud you are only getting 50-75% efficiency.
Last edited by HeadsU.P.; Jul 15, 2018 at 10:04 AM.
Race Director
Joined: Mar 2016
Posts: 14,305
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From: Napa Valley California
Start with a good aluminum radiator and new shroud.
Install a good high performance, high volume water pump like the edelbrock or others.
Look at anything that you can do to pull more air through the radiator at slow speeds or stopped like removing the front license plate and bracket and installing a center grille, replacing the front air dam.
Install a good high performance, high volume water pump like the edelbrock or others.
Look at anything that you can do to pull more air through the radiator at slow speeds or stopped like removing the front license plate and bracket and installing a center grille, replacing the front air dam.
Drifting
Joined: Aug 2009
Posts: 1,346
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From: new iberia la
check the fan CLUTCH.. its probably not holding.anymore... . get a good Hayden Severe Duty Thermal Clutch and it will make a huge difference... AND only cost you about $40
Last edited by fishslayer143; Jul 15, 2018 at 11:56 AM.
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Intermediate
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