# Tom - 65 GTO 389 3/2’s



## TominSC (Dec 26, 2021)

Still dealing with running hot here in SC. Looking for anyone that has success with electric cooling fans.
What brand and model number do you recommend?


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## Baaad65 (Aug 29, 2019)

I used Americanvolt on my '65 wih a 461, they're cheap I know but so far so good. I have a 16" puller on one switch and two 13" pushers on another switch, but there are a lot of other things that can cause overheating, many threads here if you do a search 👍


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## lust4speed (Jul 5, 2019)

Have a friend in the GTO club that spent over $1,200 for a beautiful dual electric fan setup from BeCool with an aluminum shroud. He Is very happy that his temps stay in the 190-195 range with the AC on. Meanwhile there are several of us that simply followed all the guidelines for setting up the same as what originally came on AC cars and we stay in the 165-170 range with the AC running. Twice I kept him company waiting for the auto club to show up to tow him home. Once was a melted fuse holder and the second was a melted relay.

If I were to abandon the mechanical fan, I would choose the setup I had on two drag cars - a Mark VIII fan coupled with a variable speed controller that can vary fan speeds from 30% to 100%. The electric fan and electric water pump has advantages on a drag car such as allowing the fan to continue to run after the engine is off allowing the engine to completely cool between rounds.

Again, the electric fan introduces additional complexity on the street and introduces more areas of failure than the old mechanical system. An additional failure point would include the alternator. If my alternator goes out on a hot day I can shut off any power robbing accessories and drive for over an hour to get back home. If I'm running a large electric fan pulling 40 amps, I might have 15 minutes run time.


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## armyadarkness (Dec 7, 2020)

lust4speed said:


> Have a friend in the GTO club that spent over $1,200 for a beautiful dual electric fan setup from BeCool with an aluminum shroud. He Is very happy that his temps stay in the 190-195 range with the AC on. Meanwhile there are several of us that simply followed all the guidelines for setting up the same as what originally came on AC cars and we stay in the 165-170 range with the AC running. Twice I kept him company waiting for the auto club to show up to tow him home. Once was a melted fuse holder and the second was a melted relay.
> 
> If I were to abandon the mechanical fan, I would choose the setup I had on two drag cars - a Mark VIII fan coupled with a variable speed controller that can vary fan speeds from 30% to 100%. The electric fan and electric water pump has advantages on a drag car such as allowing the fan to continue to run after the engine is off allowing the engine to completely cool between rounds.
> 
> Again, the electric fan introduces additional complexity on the street and introduces more areas of failure than the old mechanical system. An additional failure point would include the alternator. If my alternator goes out on a hot day I can shut off any power robbing accessories and drive for over an hour to get back home. If I'm running a large electric fan pulling 40 amps, I might have 15 minutes run time.


I agree.

OP, if you're looking for "trick" setup on an infrequent driver, then electric can add a nice touch. BUT if overheating is the issue, an electric fan is definitely not the cure. It's merely a bandaid... and not a good mesh one, either! One of those shitty plastic ones that doesnt stick well.

As @Baaad65 mentioned, there many threads about all of the requirements for a healthy cooling system, and as I ALWAYS mention, if everything in the system is right, then there are no problems.

I have a 17 (undersized) flex fan, no shroud, no water wetter, no radiator gaskets, and no inner fender flaps, and I run at 160, all day, in Jersey Shore temps, traffic, and humidity.

No doubt that I could replace my flex fan with an electric one, and (arguably) get the same results, but that's when adding an electric fan to an already working system.

If you put a flow cooler pump on your car, with properly clearanced plates, a be-cool or cold case radiator, and you give it a good acid bath with a thorough flush, you will run cool.

However... prior to any component replacement... I'd like to see you do a flow check and some cleaning and backwashing. Maybe bypass the heater core and see what the temps do.

How old is this engine? Have you verified the coolant flow?


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## armyadarkness (Dec 7, 2020)

Please list all of you cooling system parts, engine build specs and dates (last rebuild), and timing specs. I don't recall your specifics.


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## TominSC (Dec 26, 2021)

thank you for the feedback guys…..\The car runs cool at 160 170 while driving normal. At a light or slow traffic it bumps up quickly to 200-210. I used the infrared temp gauge at the top and bottom of the radiator as suggested. Readings were the same as the gauge. Radiator is aluminum with in and out on the same side. I installed a new 160 degree thermostat. New hoses and Evans cooling fluid. Timing is spot on. Water pump is stock. New fan clutch. Stock fan. I’d like it to stay around 170 180 when in slower traffic.


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## armyadarkness (Dec 7, 2020)

TominSC said:


> thank you for the feedback guys…..\The car runs cool at 160 170 while driving normal. At a light or slow traffic it bumps up quickly to 200-210. I used the infrared temp gauge at the top and bottom of the radiator as suggested. Readings were the same as the gauge. Radiator is aluminum with in and out on the same side. I installed a new 160 degree thermostat. New hoses and Evans cooling fluid. Timing is spot on. Water pump is stock. New fan clutch. Stock fan. I’d like it to stay around 170 180 when in slower traffic.


Okay, so assuming that your radiator is a good one... is it? Be Cool and Cold Case are not just aluminum, they are engineered high quality parts. As the saying goes, you get what you pay for.

You can buy a $200, four core, aluminum radiator off Amazon, but it's not going to cool even half as well as a two core Cold Case.

However... assuming that you have a good one, then I would focus on your water pump. If you have a stamped impeller or poorly clearanced plates, it has to go!


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## Jim K (Nov 17, 2020)

I agree with Army. If you run 160-170 while moving, then heat up when stopped or slow traffic, I'd look at your water pump and possibly your fan size/shape. The factory put muechanical fans on all their vehicles back in the day and they worked well.


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## AV68 (Aug 18, 2021)

Jim K said:


> I agree with Army. If you run 160-170 while moving, then heat up when stopped or slow traffic, I'd look at your water pump and possibly your fan size/shape. The factory put muechanical fans on all their vehicles back in the day and they worked well.


X2 water pump and pulley sizes !


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## Baaad65 (Aug 29, 2019)

Not to high jack the thread but I'm in the same boat sorta of as the OP, it's pretty good now but I'm not going to be in any parades with my car if it's over 75*. Timing is good but curved a little different than most with more initial but still 36* total 10* vacuum limiter, idle mixture good, large two core aluminum rad but not name brand with a 15*-20* difference top to bottom, 160* drilled stat, new Flowkooler pump, plates set up by Butler in 2014, slightly under driven pump pulley with a serpentine belt, a 16" 2600cfm puller fan and two 13" 2000cfm pusher fans, running distilled water with two bottles of Waterwetter and did a chemical flush this spring and a new heater core . My only flaw I can see is I'm running just a finger saving shroud which does nothing but look good and hide the puller fan. Some days I don't need any fan while moving but if it's 80* or above I'm ok until I'm stopped for a while then I've crept up to 200* with three fans running and I think it was only 80* out that time, I haven't had it out in 90* temps yet so we'll see when I get in traffic. Idk if having no shroud is the whole key or if there's something else?


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## Baaad65 (Aug 29, 2019)

....just to add it is a 461 with 9:36.1 compression and about 500hp.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Not to high jack the thread but I'm in the same boat sorta of as the OP, it's pretty good now but I'm not going to be in any parades with my car if it's over 75*. Timing is good but curved a little different than most with more initial but still 36* total 10* vacuum limiter, idle mixture good, large two core aluminum rad but not name brand with a 15*-20* difference top to bottom, 160* drilled stat, new Flowkooler pump, plates set up by Butler in 2014, slightly under driven pump pulley with a serpentine belt, a 16" 2600cfm puller fan and two 13" 2000cfm pusher fans, running distilled water with two bottles of Waterwetter and did a chemical flush this spring and a new heater core . My only flaw I can see is I'm running just a finger saving shroud which does nothing but look good and hide the puller fan. Some days I don't need any fan while moving but if it's 80* or above I'm ok until I'm stopped for a while then I've crept up to 200* with three fans running and I think it was only 80* out that time, I haven't had it out in 90* temps yet so we'll see when I get in traffic. Idk if having no shroud is the whole key or if there's something else?


It's a shame that you have underdrive pulleys. You sure don't need the few extra horse power, and it wouldve definitely improved cooling.

Why arent you bumping the initial base timing? That's what will help with being stopped. Im at almost 29 degrees with the vacuum can. Curious as to why youre being conservative... Running hotter than you need to is not good.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> ....just to add it is a 461 with 9:36.1 compression and about 500hp.


Yes, I have it tattooed on my ass cheeks, but maybe he's in Wisconsin and didnt know it.


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## ponchonlefty (8 mo ago)

TominSC said:


> thank you for the feedback guys…..\The car runs cool at 160 170 while driving normal. At a light or slow traffic it bumps up quickly to 200-210. I used the infrared temp gauge at the top and bottom of the radiator as suggested. Readings were the same as the gauge. Radiator is aluminum with in and out on the same side. I installed a new 160 degree thermostat. New hoses and Evans cooling fluid. Timing is spot on. Water pump is stock. New fan clutch. Stock fan. I’d like it to stay around 170 180 when in slower traffic.


maybe try a fan without the clutch. had a firebird that would heat up. i changed to a straight fan never had the problem again. but a new clutch on the fan should have fixed it. your stock fan should keep it cool.take a piece of paper put it in front of the radiator see if it pulls the paper toward the radiator. hope you get it fixed.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> It's a shame that you have underdrive pulleys. You sure don't need the few extra horse power, and it wouldve definitely improved cooling.
> 
> Why arent you bumping the initial base timing? That's what will help with being stopped. Im at almost 29 degrees with the vacuum can. Curious as to why youre being conservative... Running hotter than you need to is not good.


Sorry I meant slightly overdriven so faster and it's the only pulley available for that setup from CFV, I am advanced with 22* initial 14* bushing and 10* vac advance.


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## lust4speed (Jul 5, 2019)

Baaad65, we are close on specs so don't think your timing or compression can be part of the problem. My 462 with the 670 heads is 9.34:1 compression and timing is 14 initial, 38 total, and 12 degrees ported vacuum. Rear wheel horsepower is 451. Here's some areas that could be contributing to the low speed heat:

(Paragraphs removed since corrections were made below).

3. You didn't mention whether internal plates were hammered forward to tighten up the impeller/plate clearance. It's amazing how much coolant can bypass the impeller blades and just stay inside the pump.


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## armyadarkness (Dec 7, 2020)

ponchonlefty said:


> maybe try a fan without the clutch. had a firebird that would heat up. i changed to a straight fan never had the problem again. but a new clutch on the fan should have fixed it. your stock fan should keep it cool.take a piece of paper put it in front of the radiator see if it pulls the paper toward the radiator. hope you get it fixed.


There will always be ways to improve any kind of system, but I hate to see a guy spend money on improvements, when the foundation is suspect. In his case, he has a parts house water pump, and they're notoriously crappy.


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> Yes, I have it tattooed on my ass cheeks, but maybe he's in Wisconsin and didnt know it.


I knew that but it was for others missing that tattoo


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> Sorry I meant slightly overdriven so faster and it's the only pulley available for that setup from CFV, I am advanced with 22* initial 14* bushing and 10* vac advance.


Well then I wouldnt suspect any of that. Maybe get yourself a Cold Case or Bee Cool.


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## AV68 (Aug 18, 2021)

Baaad65 said:


> Sorry I meant slightly overdriven so faster and it's the only pulley available for that setup from CFV, I am advanced with 22* initial 14* bushing and 10* vac advance.


If your fine at average speeds and just low rpm slow speed issues it sounds like you need to speed up your water and air flow, I had custom pulleys made from Motor Mission Radiators in Vegas to get the most low rpm water flow I could for a Bronco, but I'm sure any machine shop could do it

I have the CVF serpentine set up on my GTO and it rarely creeps over 195 in extreme heat, gonna be 106 here today and if i leave it idling for about 20 minutes it will start to creep up to that 195 range normal driving and cruise nights pretty well parked at 185


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## armyadarkness (Dec 7, 2020)

ponchonlefty said:


> maybe try a fan without the clutch. had a firebird that would heat up. i changed to a straight fan never had the problem again. but a new clutch on the fan should have fixed it. your stock fan should keep it cool.take a piece of paper put it in front of the radiator see if it pulls the paper toward the radiator. hope you get it fixed.


My flex fan got trashed and it was discontinued by Flexalight. During my research, I screwed up and ordered a 17" fan instead of an 18". It made no difference in cooling at all... still stays firm at 160 degrees. Im sure it save a few HP by shrinking the fan diameter... would be cool to test these things.


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## Baaad65 (Aug 29, 2019)

lust4speed said:


> Baaad65, we are close on specs so don't think your timing or compression can be part of the problem. My 462 with the 670 heads is 9.34:1 compression and timing is 14 initial, 38 total, and 12 degrees ported vacuum. Rear wheel horsepower is 451. Here's some areas that could be contributing to the low speed heat:
> 
> (Paragraphs removed since corrections were made below).
> 
> 3. You didn't mention whether internal plates were hammered forward to tighten up the impeller/plate clearance. It's amazing how much coolant can bypass the impeller blades and just stay inside the pump.


I


AV68 said:


> If your fine at average speeds and just low rpm slow speed issues it sounds like you need to speed up your water and air flow, I had custom pulleys made from Motor Mission Radiators in Vegas to get the most low rpm water flow I could for a Bronco, but I'm sure any machine shop could do it
> 
> I have the CVF serpentine set up on my GTO and it rarely creeps over 195 in extreme heat, gonna be 106 here today and if i leave it idling for about 20 minutes it will start to creep up to that 195 range normal driving and cruise nights pretty well parked at 185


I'll have to measure the pulley but CFV said it's slightly overdriven and looks to have good flow with the cap off, I run about 800 rpm at idle.


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## lust4speed (Jul 5, 2019)

TominSC said:


> The car runs cool at 160 170 while driving normal. At a light or slow traffic it bumps up quickly to 200-210. I used the infrared temp gauge at the top and bottom of the radiator as suggested. Readings were the same as the gauge. Radiator is aluminum with in and out on the same side. I installed a new 160 degree thermostat. New hoses and Evans cooling fluid. Timing is spot on. Water pump is stock. New fan clutch. Stock fan. I’d like it to stay around 170 180 when in slower traffic.


Not all fan clutches leave the manufacturer at spec. I've returned several after they failed to firm up as coolant temps increased. If a clutch is defective it can't be fixed. If it is good and coming in late, you can tweak the thermal spring since most end up increasing about 200° and slightly altering it can get it to come on 20° to 30° sooner.

I like stock cast iron water pumps. After testing and being around many of the trick and very trick aluminum pumps I've found that we can't tell any cooling difference solely from the type of pump. They don't do any harm, but not much good either. Just purchased the cheapest 8-bolt cast iron water pump Butler had on their page and it is now installed and doing a great job. The main point on this is the proper clearancing of the plate(s) to the water pump impeller. Nothing else makes as much difference is getting the plates nice and close to the impeller.

Many of our club guys have went with Champion radiators. The plant is close to us and the radiators can be ordered and picked up in a few days. and seem to actually work pretty good for the cheaper cost. If I had one I'd keep it, but my radiator of choice is the Cold Case.


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## Baaad65 (Aug 29, 2019)

lust4speed said:


> Baaad65, we are close on specs so don't think your timing or compression can be part of the problem. My 462 with the 670 heads is 9.34:1 compression and timing is 14 initial, 38 total, and 12 degrees ported vacuum. Rear wheel horsepower is 451. Here's some areas that could be contributing to the low speed heat:
> 
> (Paragraphs removed since corrections were made below).
> 
> 3. You didn't mention whether internal plates were hammered forward to tighten up the impeller/plate clearance. It's amazing how much coolant can bypass the impeller blades and just stay inside the pump.


I gave up the mechanical fan because of to much drag on the belt causing it to screech, then I tightened it to much blowing out the bearings on the pump. I don't know anything about the plates as Butler assembled it and I never removed the timing cover, all I did when the pump went bad was replace the pump with the same one.


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## AV68 (Aug 18, 2021)

Baaad65 said:


> I
> 
> I'll have to measure the pulley but CFV said it's slightly overdriven and looks to have good flow with the cap off, I run about 800 rpm at idle.


You can try letting it idle for 1/2 an hour at 800 rpm record the temps then try letting it idle at 1100 rpm for 1/2 an hour and see if it changes anything
I did that with the bronco the stock set up would hit 225 in about 10-15 minutes had the custom pulleys made and it can idle for over an hour and doesn't break 180 only difference were the pulley sizes


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## AV68 (Aug 18, 2021)

Baaad65 said:


> I gave up the mechanical fan because of to much drag on the belt causing it to screech, then I tightened it to much blowing out the bearings on the pump. I don't know anything about the plates as Butler assembled it and I never removed the timing cover, all I did when the pump went bad was replace the pump with the same one.
> View attachment 154654
> 
> View attachment 154655


looks like your plate is too close at the ends, yo might want to reshape it some


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## Baaad65 (Aug 29, 2019)

AV68 said:


> looks like your plate is too close at the ends, yo might want to reshape it some


The ends meaning by the outside holes, can you point it out on the picture and to close to what the pump?? The impeller left marks when the bearings let go. Like I said Butler set this up so I assumed it was done right, I just RRd the pump.


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## Baaad65 (Aug 29, 2019)

AV68 said:


> You can try letting it idle for 1/2 an hour at 800 rpm record the temps then try letting it idle at 1100 rpm for 1/2 an hour and see if it changes anything
> I did that with the bronco the stock set up would hit 225 in about 10-15 minutes had the custom pulleys made and it can idle for over an hour and doesn't break 180 only difference were the pulley sizes


Thanks, worth a try.


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## Baaad65 (Aug 29, 2019)

I'm going to look up the radiator too, I know it was a larger two core and was a reputable eBay seller but it is not a name brand probably from china.


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## lust4speed (Jul 5, 2019)

I've ordered out quite a few pumps and plate combinations from Butler and have never seen them adjust the plates. Your Flowkooler pump will be pretty close out of the box but should still be checked. Basically the plate should touch or almost touch the plate with no gasket in place with the plate on the pump. Then the gasket thickness becomes the clearance from impeller to plate.


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## Baaad65 (Aug 29, 2019)

lust4speed said:


> I've ordered out quite a few pumps and plate combinations from Butler and have never seen them adjust the plates. Your Flowkooler pump will be pretty close out of the box but should still be checked. Basically the plate should touch or almost touch the plate with no gasket in place with the plate on the pump. Then the gasket thickness becomes the clearance from impeller to plate.


Thanks for the help....I couldn't tell you how close it was because I didn't take the plate off when I did the pump, didn't want take apart more than I had to and just assumed Butler checked all that. I can't remember if I tried the pump without the gasket to see if it rubbed either, but I really don't want to tear it apart again if I don't have to.


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## lust4speed (Jul 5, 2019)

With the Flowkooler you should be pretty close. I probably should put in a disclaimer while I'm at it that the Flowkooler impellers are usually pretty close out of the box, and the reason my cast iron pumps work good is that I take the time to hammer in the plate. If the cast iron was taken right out of the box I could see where it would come in a poor second to the expensive aluminum aftermarket pumps because of excessive plate clearance.

The bearing failing might not have anything to do with belt tension. Many years ago Cardone brought out their first new Pontiac water pump. I had three bearing failures in a row. Pump had a lifetime warranty but it was a pain to do the replacement and the last time the blades clipped the tubes and cost me a re-core of the desert cooler radiator. The Flowkooler might have been defective and it would have crashed with normal tension.


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## TominSC (Dec 26, 2021)

Another senior moment …… I bought this car last November from a classic car dealer in Texas. It has an after market AC unit. I’ve been going through it little by little. I’m embarrassed to say I just noticed a cooler grill about the size of the radiator grill mounted 2” in front of the radiator. the AC grill has to be restricting air flow And causing the high heat at idle Without the AC running.


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## lust4speed (Jul 5, 2019)

That's the condenser for the AC unit. While it does contribute a very marginal restriction it really isn't that much. I added Vintage Air about 5 years ago and engine still runs at thermostat with the AC running, and definitely not a problem with the AC off. The new aftermarket units are so much more efficient than the original stock units and don't put near the load on the cooling system.


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## lust4speed (Jul 5, 2019)

This is my '67 GTO "Cruiser" that had the stock AC system. One of the changes I made was to install a Lexus 400 condenser to increase cooling capacity. While it didn't really increase AC cooling efficiency it also didn't hurt the cooling capacity for the engine coolant. Condenser was massive and basically occupied 100% of the opening.


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## Baaad65 (Aug 29, 2019)

lust4speed said:


> With the Flowkooler you should be pretty close. I probably should put in a disclaimer while I'm at it that the Flowkooler impellers are usually pretty close out of the box, and the reason my cast iron pumps work good is that I take the time to hammer in the plate. If the cast iron was taken right out of the box I could see where it would come in a poor second to the expensive aluminum aftermarket pumps because of excessive plate clearance.
> 
> The bearing failing might not have anything to do with belt tension. Many years ago Cardone brought out their first new Pontiac water pump. I had three bearing failures in a row. Pump had a lifetime warranty but it was a pain to do the replacement and the last time the blades clipped the tubes and cost me a re-core of the desert cooler radiator. The Flowkooler might have been defective and it would have crashed with normal tension.


I think mine did because I cranked it up so tight trying to get the squeal out, now I have a new RPM belt and adjusted it to be pretty loose when cold and it's perfect when hot.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> I couldn't tell you how close it was


We are friends, you can tell me anything.


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## armyadarkness (Dec 7, 2020)

Baaad65 said:


> I think mine did because I cranked it up so tight trying to get the squeal out, now I have a new RPM belt and adjusted it to be pretty loose when cold and it's perfect when hot.


I'm confused, how did you tighten it too much if it's a serpentine belt.?


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## PontiacJim (Dec 29, 2012)

TominSC said:


> Still dealing with running hot here in SC. Looking for anyone that has success with electric cooling fans.
> What brand and model number do you recommend?


Well, I think you bought a lemon with all the issues you have been having with that car.

In stop/go traffic where airflow is lower, engine temps will go up. 200-205 degrees is really OK. It seems to pull right back down once rolling. If it went more than 205 degrees, then I would be a little concerned. If you bring the RPM's up when it begins to get hot, ie push in the clutch and rev the engine up to 1,000 RPM's for a brief time, does it drop down? My '73 Fury owner manual tells to do exactly this when the water temps begin to get hot - put the car in neutral and raise the engine RPM's using the gas pedal.

BEFORE you start looking at it as a cooling issue.........

The 1965 GTO radiator comes in 2 sizes - the standard 15" high and 17.5" high for AC/Heavy Duty.

Supply us with several photos of the engine bay with the radiator/AC condensor for us to look at for review.

Give us the measurements of whatever radiator you now have in there. If too small, or wrong style, you may be wasting your money and time with electric fans. 3 & 4 cores does not mean it will cool better as depending on the maker, if the cores are too small in diameter or the spacing is too tight, the extra cores can actually cause a cooling problem as airflow can be reduced.

What is your idle speed in neutral?*_*

List your timing numbers:

What is your initial timing set at at the balancer - Vacuum advance hose disconnected and port plugged?*____*

What does your initial timing jump up to when you reconnect the Vacuum advance hose to the distributor?*___*

Revving up the engine - using a dial-back timing light OR a timing light and timing tape on the balancer, at what RPM does your balancer timing stop AND at what RPM?*___*
Example - 36 degrees on the balancer at 3,000 RPM's and the timing no longer moves.

What brand and number spark plug (heat range) do you use?*___*


DID you add all the rubber baffles required for a 1965 GTO with AC to direct the airflow through the radiator? Yes/No

Do you know what size jets are used in the center carb?*_*
What is your idle air/fuel ratio?*_*
Is your center carb running lean???*__*


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## Baaad65 (Aug 29, 2019)

armyadarkness said:


> I'm confused, how did you tighten it too much if it's a serpentine belt.?


It's got a turn buckle on the alternator...want pictures 😁


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## BearGFR (Aug 25, 2008)

I run twin electrics behind a good aluminum radiator and a good water pump with a properly clearanced plate on my '69 with a "reasonably healthy" 461. Still, "I've been told" that -nothing- cools better than the good 7-blade factory fan, properly clearanced inside the correct shroud (1/2 in and 1/2 out) driven by a good clutch.

I'm running those electrics because back when I was building this thing I was interested in making all the power I could, but now that I've had them for close to 10 years, let me tell you: there's a WHOLE lot to be said for the advantages of keeping things simple. With a mechanical fan, you never have to worry about losing a fan motor, losing a relay, blowing a fuse, having to upgrade the alternator to pull the load, etc. Any one of those things can leave you stranded on the side of the road with electric fans.

Bear


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## Baaad65 (Aug 29, 2019)

lust4speed said:


> With the Flowkooler you should be pretty close. I probably should put in a disclaimer while I'm at it that the Flowkooler impellers are usually pretty close out of the box, and the reason my cast iron pumps work good is that I take the time to hammer in the plate. If the cast iron was taken right out of the box I could see where it would come in a poor second to the expensive aluminum aftermarket pumps because of excessive plate clearance.
> 
> The bearing failing might not have anything to do with belt tension. Many years ago Cardone brought out their first new Pontiac water pump. I had three bearing failures in a row. Pump had a lifetime warranty but it was a pain to do the replacement and the last time the blades clipped the tubes and cost me a re-core of the desert cooler radiator. The Flowkooler might have been defective and it would have crashed with normal tension.


Measured the pump pulley and close as I can get the ruler it looks like 5 1/8- 5 1/4" so idk what the stock pulley is?


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## Baaad65 (Aug 29, 2019)

Thanks TominSC for letting me hop on, hopefully we both get things figured out 👍


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## armyadarkness (Dec 7, 2020)

BearGFR said:


> I run twin electrics behind a good aluminum radiator and a good water pump with a properly clearanced plate on my '69 with a "reasonably healthy" 461. Still, "I've been told" that -nothing- cools better than the good 7-blade factory fan, properly clearanced inside the correct shroud (1/2 in and 1/2 out) driven by a good clutch.
> 
> I'm running those electrics because back when I was building this thing I was interested in making all the power I could, but now that I've had them for close to 10 years, let me tell you: there's a WHOLE lot to be said for the advantages of keeping things simple. With a mechanical fan, you never have to worry about losing a fan motor, losing a relay, blowing a fuse, having to upgrade the alternator to pull the load, etc. Any one of those things can leave you stranded on the side of the road with electric fans.
> 
> Bear


This is a perfect example of what I was saying in the beging:

Nothing wrong with electric fans, if that's what you want, but don't expect them to solve cooling problems, resulting from inadequacy somewhere else in the system.


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## WildTom65 (Apr 21, 2014)

I went the same way your thinking, but going electric didn't cure my running hot issue. After ensuring that I had proper engine timing, a friend suggested to perform a vacuum test. What I found was that I had a intake manifold and also a tripower carb stud leak. My engine was running too lean as a result. A pro shop initially installed these items. I wound up redoing it myself with positive results.


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## Droach6498 (Nov 1, 2020)

TominSC said:


> thank you for the feedback guys…..\The car runs cool at 160 170 while driving normal. At a light or slow traffic it bumps up quickly to 200-210. I used the infrared temp gauge at the top and bottom of the radiator as suggested. Readings were the same as the gauge. Radiator is aluminum with in and out on the same side. I installed a new 160 degree thermostat. New hoses and Evans cooling fluid. Timing is spot on. Water pump is stock. New fan clutch. Stock fan. I’d like it to stay around 170 180 when in slower traffic.


Theres aguy on Utube who tests his 69 GTo with a valve between the head and heater core, very detailed, it runs cooler at 3/4 closed valve. Fast Monty on youtube. It shows you need to have your coolant in the radiator as long as possible


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## Baaad65 (Aug 29, 2019)

So what is the stock water pump pulley size, I have '65 car with a '72 motor, am I over driven slightly?


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## PontiacJim (Dec 29, 2012)

*PJ:* I did not see your conclusion on your heating issues.

*TominSC*: Heat issue solved, carbs had incorrect gaskets. spacers and fuel regulator solved hot start issue.

I bought a radiator with the inlet and outlet on opposite sides. I also installed a 14" diameter electric fan in front of the AC cooler with an on/off switch under the dash. When in traffic and temp climbs to 190 I'll engage the electric fan to keep it at or below 190 until I start moving again.


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