Increased Cooling with Electric Fan and Electric Water Pump

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drumvirt

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I have an '85 454 Dually w/granny gear and Quadrajet that I occasionally have a problem cooling when I've been driving at highway speeds and outside temp hits about 95 or more. I'm lookin for suggestions and here's what I've learned so far: First, the consensus seems to be that a good electric fan is better than mechanical. Do you agree?
Second, can I wire the fan to continue running for a set time period after the engine shuts off, or, until a temp sensor tells the fan to shut off?
Third, will an electric water pump cool the big 454 better than a mechanical one?
Fourth, can I wire the pump to continue running for a set time period after the engine shuts off, or, until a temp sensor tells the pump to shut off?
Lastly, I don't want to buy a new hood with a scoop to allow the underhood hot air to escape. I'm hoping the other ideas will work.

What do y'all think and what have you tried?
 
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MarineOne

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So an electric fan and waterpump will provide you more cooling at idle and low engine speeds (under 1500rpm) a good flex fan and waterpump is far superior cooling power at engine speed. That's why modern 3/4 ton and 1 ton trucks still use mechanical fans and water pumps.

Also on that note at highway speed an electric or mechanical fan is prettymuch doing nothing as air flow purely from driving is enough airflow.

What is your current setup for radiator,shroud,fan,waterpump,hoses and is your grill factory or aftermarket. Also are pulleys original?

What is ignition setup?
Do you know what base timing is, mechanical max advance and what it is for vaccum advance?

Is q jet properly adjusted ?

If ignition is properly set and carb is properly adjusted my recommendation would be flush entire cooling system
If radiator is original I'd get a good 3 or 4 row aluminum rad. A proper shroud to fit the largest flex fan possible. A good high quality waterpump.

If you did go electric fan/waterpump route (probably would make issue worse) yes they can be wired to run after shutdown flexalite has a controller that runs after shutdown and you can also wire it to a second temp sensor that is preset as an on off only sensor and it would force fans/pump on until it drops bellow point temperature switch is set for. (I run this setup on my drag car)
 

SirRobyn0

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@drumvirt I'm not saying this is your problem, but before you dive into making major cooling system changes let me pop some ideas past you.

1st, if this is occurring on the highway no amount of fan is going to help, the air speed at 55+ (maybe even 45+) is going to be cooling the radiator not any fan and since you don't have over drive that mechanical pump is already rolling the coolant though. I doubt an electric pump and fan will help.

So I had a 1977 Dodge class C motorhome that constantly wanted to run hot in 80+ degree weather. It would never really overheat it just would get a bit hotter than normal on the flats and I'd have to take it easy on the hills or it would actually overheat. I spent a lot of money on the cooling system and nothing helped. Eventually I came to discover the parts store reman'd carb the PO installed, had leaner jet (I think 2 steps leaner) than was called for. Correcting that corrected the running hot. So in that case the engine was running hot, because it was lean and therefore making to much heat.

Clogged radiator. I've seen this before BB engine turning 2,500 - 3K on the highway and the radiator is 1/2 clogged, so it can't expel the heat like it should.

If you have a problems with it percolating, or vapor locking as well, the heat riser might not be opening all the way and putting to much heat into the manifold some of that heat ends up transferred in to the cooling system as well.

A few years back we had a late 70's Dodge van in the shop. Customer was complaining of it running hot in the summer and hard starting when warmed up. In his case, he had dual exhaust with no H-pipe or X-pipe so each side was independent. For some reason the passenger side muffler had more flow resistance than the drivers side, therefore on the highway that excess resistance resulted in exhaust gas going though the manifold cross over all the time.

Remember your truck when it was new had a mechanical fan and water pump and stayed cool. I think something is wrong, hopefully I gave you some ideas.
 

Frankenchevy

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The best dual e-fans money can buy properly shrouded might pull 5000cfm. Many mechanical fans pull 10,000cfm. In other words, I wouldn’t look to an e-fan to solve cooling issues.
 

rusted nuts

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If every thing is right stock part should keep it in the right temp. zone,, Oil cooler help keep them cooler too
 

drumvirt

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So an electric fan and waterpump will provide you more cooling at idle and low engine speeds (under 1500rpm) a good flex fan and waterpump is far superior cooling power at engine speed. That's why modern 3/4 ton and 1 ton trucks still use mechanical fans and water pumps.

Also on that note at highway speed an electric or mechanical fan is prettymuch doing nothing as air flow purely from driving is enough airflow.

What is your current setup for radiator,shroud,fan,waterpump,hoses and is your grill factory or aftermarket. Also are pulleys original?

What is ignition setup?
Do you know what base timing is, mechanical max advance and what it is for vaccum advance?

Is q jet properly adjusted ?

If ignition is properly set and carb is properly adjusted my recommendation would be flush entire cooling system
If radiator is original I'd get a good 3 or 4 row aluminum rad. A proper shroud to fit the largest flex fan possible. A good high quality waterpump.

If you did go electric fan/waterpump route (probably would make issue worse) yes they can be wired to run after shutdown flexalite has a controller that runs after shutdown and you can also wire it to a second temp sensor that is preset as an on off only sensor and it would force fans/pump on until it drops bellow point temperature switch is set for. (I run this setup on my drag car)
 

drumvirt

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@drumvirt I'm not saying this is your problem, but before you dive into making major cooling system changes let me pop some ideas past you.

1st, if this is occurring on the highway no amount of fan is going to help, the air speed at 55+ (maybe even 45+) is going to be cooling the radiator not any fan and since you don't have over drive that mechanical pump is already rolling the coolant though. I doubt an electric pump and fan will help.

So I had a 1977 Dodge class C motorhome that constantly wanted to run hot in 80+ degree weather. It would never really overheat it just would get a bit hotter than normal on the flats and I'd have to take it easy on the hills or it would actually overheat. I spent a lot of money on the cooling system and nothing helped. Eventually I came to discover the parts store reman'd carb the PO installed, had leaner jet (I think 2 steps leaner) than was called for. Correcting that corrected the running hot. So in that case the engine was running hot, because it was lean and therefore making to much heat.

Clogged radiator. I've seen this before BB engine turning 2,500 - 3K on the highway and the radiator is 1/2 clogged, so it can't expel the heat like it should.

If you have a problems with it percolating, or vapor locking as well, the heat riser might not be opening all the way and putting to much heat into the manifold some of that heat ends up transferred in to the cooling system as well.

A few years back we had a late 70's Dodge van in the shop. Customer was complaining of it running hot in the summer and hard starting when warmed up. In his case, he had dual exhaust with no H-pipe or X-pipe so each side was independent. For some reason the passenger side muffler had more flow resistance than the drivers side, therefore on the highway that excess resistance resulted in exhaust gas going though the manifold cross over all the time.

Remember your truck when it was new had a mechanical fan and water pump and stayed cool. I think something is wrong, hopefully I gave you some ideas.

@drumvirt I'm not saying this is your problem, but before you dive into making major cooling system changes let me pop some ideas past you.

1st, if this is occurring on the highway no amount of fan is going to help, the air speed at 55+ (maybe even 45+) is going to be cooling the radiator not any fan and since you don't have over drive that mechanical pump is already rolling the coolant though. I doubt an electric pump and fan will help.

So I had a 1977 Dodge class C motorhome that constantly wanted to run hot in 80+ degree weather. It would never really overheat it just would get a bit hotter than normal on the flats and I'd have to take it easy on the hills or it would actually overheat. I spent a lot of money on the cooling system and nothing helped. Eventually I came to discover the parts store reman'd carb the PO installed, had leaner jet (I think 2 steps leaner) than was called for. Correcting that corrected the running hot. So in that case the engine was running hot, because it was lean and therefore making to much heat.

Clogged radiator. I've seen this before BB engine turning 2,500 - 3K on the highway and the radiator is 1/2 clogged, so it can't expel the heat like it should.

If you have a problems with it percolating, or vapor locking as well, the heat riser might not be opening all the way and putting to much heat into the manifold some of that heat ends up transferred in to the cooling system as well.

A few years back we had a late 70's Dodge van in the shop. Customer was complaining of it running hot in the summer and hard starting when warmed up. In his case, he had dual exhaust with no H-pipe or X-pipe so each side was independent. For some reason the passenger side muffler had more flow resistance than the drivers side, therefore on the highway that excess resistance resulted in exhaust gas going though the manifold cross over all the time.

Remember your truck when it was new had a mechanical fan and water pump and stayed cool. I think something is wrong, hopefully I gave you some ideas.
Thanks David, somehow I screwed my reply to you right after the Quadrajet section and lost it all. Got worse as I attempted to fix it. I can't redo right now but will say the problem is after I come off highway speeds, in stopped traffic or at a light, in mid-90 degree summer days. Stalls and hard to restart. Will answer more later.
 

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Thanks David, somehow I screwed my reply to you right after the Quadrajet section and lost it all. Got worse as I attempted to fix it. I can't redo right now but will say the problem is after I come off highway speeds, in stopped traffic or at a light, in mid-90 degree summer days. Stalls and hard to restart. Will answer more later.
You quote me and I'm Rob, if that's just a name mixup do not worry about. more later is fine I'll be out for most of the rest of the day but based on this little bit my first suspect would be one of the exhaust issues I mentioned and / or fan clutch.
 

RetroC10Sport

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On my '89, the clutch fan was new but not adequately cooling. i installed a mid 90s Thunderbird fan and it stays at 190 on a 115 degree day with the A/C on.
 

drumvirt

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You quote me and I'm Rob, if that's just a name mixup do not worry about. more later is fine I'll be out for most of the rest of the day but based on this little bit my first suspect would be one of the exhaust issues I mentioned and / or fan clutch.
Thanks Rob. Your heat riser idea sounds very plausible so I'll check it/probably gut it, saving the main part for a spacer. Ditto for checking the fan clutch. I replaced the radiator 5 to 7 years ago with the BeCool Aluminum that Summit recommended for my 454, not realizing I shoulda gotten a 3 or 4 row and not a 2 row. I trusted their recommendation. My bad.

Carb is well adjusted by expert who was the go to guy among the local racers and operates well, except if the truck sits for 5 or 6 days I have to wait about 1.5 min. for the aftermarket Carter electric pump to bring fuel back up. I think it's evaporating because no gasoline smell in the oil ever. He said it needed epoxying, but he "retired".

I don't trust the water pump because I just noticed an almost imperceptible trace of antifreeze near the pump. If I change, why not an electric that I can set to continue running for a short time after the engine shuts off?

Finally, one known adjustment needed is the amount of fan blade showing past the open edge of the shroud. One half inch is recommended. Mine is a 1/4" or less.

Now to find the time to do it!
 

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A little history on my problems with cooling a high performance engine. Bought my 2002 Dodge 3500 dually new in Sep 2002. Equipped with a Cummins 5.9 HO engine with a NV 5600 6 spd manual trans. Used it to pull my 40' triple axle GN farm trailer, and later our 39' triple axle Carriage 5th wheel. Worked well until about 120,000 on the odometer. Then I noticed the temp gauge start to rest more on the 210 marking on the gauge rather than the 190 range. Nothing had changed except the mileage. Pea brain thinking that something has degraded to make it run warmer. The engine per say wasn't the problem, just portions of the engine at the front of it. Drained all the coolant, including the block and heater core. Pulled the radiator and had it checked/cleaned by a reputable shop.
Pulled the fan clutch and tensioner and replaced them with Haynes and Gates new units+new Gates belt. Replaced the 190 thermostat with a 160. Installed everything along with new coolant. Results were great. With the 39' 5th wheel at 17,000, the engine was running a temp of about 170-175. Which was the one defining fix? Don't know and don't care. All the items replaced were probably worn out to the point of not working as they had new. The 160 thermostat just allows the cooling system to do its trick a bit earlier than the stock 190. Once a cooling system gets behind the power curve, it will probably never catch up.
 

Camar068

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A good read on E fans would be at the link below.

GMSB E-Fans
 

SirRobyn0

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Thanks Rob. Your heat riser idea sounds very plausible so I'll check it/probably gut it, saving the main part for a spacer. Ditto for checking the fan clutch. I replaced the radiator 5 to 7 years ago with the BeCool Aluminum that Summit recommended for my 454, not realizing I shoulda gotten a 3 or 4 row and not a 2 row. I trusted their recommendation. My bad.

Carb is well adjusted by expert who was the go to guy among the local racers and operates well, except if the truck sits for 5 or 6 days I have to wait about 1.5 min. for the aftermarket Carter electric pump to bring fuel back up. I think it's evaporating because no gasoline smell in the oil ever. He said it needed epoxying, but he "retired".

I don't trust the water pump because I just noticed an almost imperceptible trace of antifreeze near the pump. If I change, why not an electric that I can set to continue running for a short time after the engine shuts off?

Finally, one known adjustment needed is the amount of fan blade showing past the open edge of the shroud. One half inch is recommended. Mine is a 1/4" or less.

Now to find the time to do it!
Some guys are happy removing the heat riser and running it, but do keep in mind there is some potential for some runability issues when the truck is cold and you need to step on the gas hard, for example going up a steep hill or towing a trailer. What can happen is instead of the fuel mixture vaporing properly it puddles on the bottom of the intake. This results in lack of power so you step on the gas harder which causes more pooling and then flooding. If your thermac works and you plan to keep it that will lessen the issue. I'm not telling you not to remove the heat riser I'm jut letting you know there is that potential.

Another concern with the electric water pump, and fan that has not been brought up is power draw. Most of these trucks are running around with alternators that are rated from somewhere between 60 - 80 amps. You'd want to figure out the draw of all the lighting, heater fan, wipers, radio and the electric water pump and fan. Next thing you know you need a larger alternator, then you have 120 amp (or possibly higher) alternator needed. Then you'd need to think about whether one single V-belt will be able to drive the alternator or if you'd be looking at needing a serp belt conversion. I'm just throwing that out there as well.
 

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