Increased Cooling with Electric Fan and Electric Water Pump

[Camar068]

If it's the original radiator, I'd try to have that radiator repaired if it's minor and you have a shop close to you. I'm lucky and minor repairs/mods are under $50. Old radiators are typically better than the new aluminum/plastic tank ones. Or you can pay more for all aluminum new.

 

[MarineOne]

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!

That be cool 2 row is equivalent to a 4 row as the cores in there rads are thicker

Electronic waterpump willnot help your issue as at engine speed they flow significantly less water

If it were me I'd get a flex fan with proper spacing a new water pump and put a bottle of water wetter in with coolant (dropped coolant temp 10 degrees in my trans am)

I'd also flush block while I'm in there because why not

 

[drumvirt]

That be cool 2 row is equivalent to a 4 row as the cores in there rads are thicker

Electronic waterpump willnot help your issue as at engine speed they flow significantly less water

If it were me I'd get a flex fan with proper spacing a new water pump and put a bottle of water wetter in with coolant (dropped coolant temp 10 degrees in my trans am)

I'd also flush block while I'm in there because why not

Thanks for the info, David. I'll stick with my be cool then.

I'm researching the electric water pump. A good one pumps 35 real world gpm and an average 454 cruisin at 65 mph runs between 2200 and 3000 rpm with the aftermarket "mechanical" pump averaging 38 to 51 gpm. You're right, less gpm, but it's not too much different. I'm mainly lookin for high flow at low rpm when the BBC starts warmin up, plus the advantage of having it run with engine off for a bit to cool internal hotspots 454's are known to have, until the pump's thermostat shuts it off. Of course, only an electric fan on the same thermostat will pull air through the radiator to lower the coolant temp. Probably higher power alternator and battery also needed for that.

I've kicked around water wetter but without a bonafide recommendation I hadn't used it. Thanks! I'll get some next trip past the parts store and use it! Also, yep, why not block flush when it hasn't been done since 5 to 6 years ago when I put the new rad. in.

 

[rusted nuts]

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.

You want a diesel to run at least 180 to burn the fuel like it should. Maybe 190

 

[oldretiredafguy]

You want a diesel to run at least 180 to burn the fuel like it should. Maybe 190

Disagree.

 

[CatRacer]

The EMP/Stewart stage 2 mechanical waterpumps are among the very best waterpumps you can buy.
Pair it with a high flow thermostat and you have a combination for a very effective cooling setup.

 

[73cheyenne]

From my experience with engines running hot, have you checked or replaced the thermostat? Put it in a pan of water on the stove with a thermometer next to it and make sure it opens all the way at the proper temp. If the thermostat is good, the radiator may be partially plugged. If so I'd replace it with the biggest and thickest one that will fit.
I replaced the stock fan on my '73 with a clutch fan years ago, and a 4 row radiator to replace the old 3 row that came in it. After almost 50 years it was leaking.

 

[Bextreme04]

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.

This is not true. The problem most vehicles have is staying cool at idle or low speed. A mechanical fan is usually going to have a very small window where it is flowing well. An electric fan is always at 100% efficiency and airflow. Once above about 40mph, you are pushing more than 20,000cfm through the grill just from driving through the air mass. So at idle an electric fan is flowing far more than a mechanical fan unless you have it in neutral and the engine at several thousand rpm and at highways speed you just need the fans to get out of the way. A dual electric fan on a broad radiator like the stock GMT-400 454 radiators has a ton of surface area to let the air through at highway speed and a low/high speed that flows plenty to keep the engine cool at idle. I never have mine come on for more than about 15-20 seconds on low in the summer at 95 degrees or so. They never come on when at highway speed.

 

[SquareRoot]

Avoid the widow maker flex fans. Inefficient and make a lot of noise. If you are gonna use mechanical, use a fixed blade and fan clutch like the factory does. Through much trial and error my setup consists of Dual Spal electric fans with a blow thru shroud. They're controlled via the EFI and fully programmable. A two core all aluminum radiator with 195 stat. Engines are more efficient and make less emissions at higher temps WHEN the air inlet temp is kept cool (relatively). I can sit idle with my AC on here in the Arizona desert in the summer when it's 120 and the temp stays at 205 at the cylinder heads. Carry on.

 

[Grit dog]

Disagree.

Disagree with your disagreement.
If talking anything made in or near this century.

 

[Grit dog]

@drumvirt
IMO unless you’re trying to get fancy, get the entire cooling system up to OEM spec. It will be more than sufficient. Unless maybe you’re trying to pull 10klbs thru Death Valley uphill with the AC on in July.

 

[Bennyt]

@drumvirt
IMO unless you’re trying to get fancy, get the entire cooling system up to OEM spec. It will be more than sufficient. Unless maybe you’re trying to pull 10klbs thru Death Valley uphill with the AC on in July.

This!

Flush the block, hoses, radiator. I even recommend removing the plugs at the bottom of block and making sure they aren't clogged.

I like using the Mr. Gasket Rad caps that have the built in gauge as a second source of truth.

Flush the heater core as well.

Buy a good replacement water pump(preferably aluminum). I like Stewart, Edelbrock, TRW used to be good, but don't know anymore.

Make sure the pulleys and belt are good and not slipping.

Check fan clutch, fan and shroud are all good. Factory fan is fine but see if GM had a heavier duty version than what you have and upgrade if possible.

Make sure your trans is running at correct temp and not putting too much heat into radiator.

Water wetter works and drops a few degrees but doesn't cure problems. Also, Evans helps but expensive.

 

[Matt69olds]

Make sure ALL the factory baffles/shrouding is around the radiator and core support. Make sure the shroud fits tight up against the radiator. Any airflow that can go around the radiator instead of thru it is wasted air.

Before wasting too much time and money on this, make sure it’s actually overheating.

 

[drumvirt]

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.

Right, thanks. I've considered possible need for a higher capacity battery, too. I don't rush into this kinda stuff so I appreciate all these suggestions. I't will stew in my brain for a while, and I'll look up some more stuff and consider all forum cautions/suggestions. Then try not to screw anything up.

 

[Frankenchevy]

This is not true. The problem most vehicles have is staying cool at idle or low speed. A mechanical fan is usually going to have a very small window where it is flowing well. An electric fan is always at 100% efficiency and airflow. Once above about 40mph, you are pushing more than 20,000cfm through the grill just from driving through the air mass. So at idle an electric fan is flowing far more than a mechanical fan unless you have it in neutral and the engine at several thousand rpm and at highways speed you just need the fans to get out of the way. A dual electric fan on a broad radiator like the stock GMT-400 454 radiators has a ton of surface area to let the air through at highway speed and a low/high speed that flows plenty to keep the engine cool at idle. I never have mine come on for more than about 15-20 seconds on low in the summer at 95 degrees or so. They never come on when at highway speed.

Not sure anything I said is untrue. I’ve yet to see an aftermarket fan pull more than about 2500cfm each.

I called all the oem quality suppliers. I just ordered a Griffin radiator for my older Cummins. I talked to one of their tech guys who adamantly talked me out of their dual spal setup even though it would’ve turned my $1300 order into a $2000 order from them.

I stand by the premise that one should not try to solve an overheating problem on a truck being “driven at highway speeds” as the OP stated with an e-fan. There’s something else going on if the OEM setup is insufficient.

It’s hard to say a truck is pulling 20,000 cfm across its radiator above 40mph without taking into consideration all factors. I’ve yet to come across a test with an anemometer showing that. What I have seen are bench flow tests that actually show that many e-fans restrict air flow through the radiator more so than a large shroud from a single clutch fan. I’d guess it’s due to the shroud’s shape and the smaller openings of E-fans have more stuff in the way i.e. several more tightly spaced blades and a tightly spaced grill behind the fan blades.

I would agree that e-fans are capable and a viable choice for lighter duty applications, but they are not a smoking gun to solving overheating and I certainly wouldn’t tow heavy with one.