Electric Fan on Deuce

[Chevytruck]

From the -20 TM

Brake Horsepower:
Gross (fan belt removed; air compressor
turning but unloaded. . . . . . . . . . . . . . . . . . . . . 130 hp (min) @ 2600 rpm

Net (fan belt installed; alternator and
air compressor turning but unloaded) . . . . . . . . . . . . . 118 hp @ 2600 rpm

 

[Parker2]

I would suggest trying a fan or two from a Lincoln Mark VIII. They are great fans and move a lot of air. I have two on my Dodge cummins and have been very happy. So much better than the stock fan.

 

[Kohburn]

nearly 10% power loss is pretty significant. seems like a worthwhile upgrade if it is all worked out well.

 

[mikew]

The reason the Deuce (or just about any vehicle) heats up at highway speed when you don't run a fan of some sort, is because air hits the front axle and other low hanging parts and builds a little bit of pressure in the engine compartment. That makes the air pressure on the front side of the radiator only a little greater than the back side, so not much are flows through the radiator.

What you need is an "air dam", something that guides the air more downward, under the front axle (thus lowering the air pressure in the engine compartment). I was thinking about a skid plate just for that purpose.

 

[militarysteel]

you may not want to hear this... i think you have a head gasket leak, compression is getting into the coolant system,

got a buddy in northern mi, he's got 6 trucks, no issues in the summer or winter, your winters and summers are no different.

stop wasting time and money, hook it all back up the right way, and drive it,

check to make sure your head gasket is good, oil leaking down the block is the first sign your gasket needs to be replaced.

 

[JasonS]

you may not want to hear this... i think you have a head gasket leak, compression is getting into the coolant system,

got a buddy in northern mi, he's got 6 trucks, no issues in the summer or winter, your winters and summers are no different.

stop wasting time and money, hook it all back up the right way, and drive it,

check to make sure your head gasket is good, oil leaking down the block is the first sign your gasket needs to be replaced.

You may be on to something. I had a 302 GMC that would run hot. Ended up being a minor head gasket leak.

I ordered a 24V, 16" fan from ebay for $47 shipped. Wanted to try it out and see how effective it would be.

 

[Kohburn]

you may not want to hear this... i think you have a head gasket leak, compression is getting into the coolant system,

got a buddy in northern mi, he's got 6 trucks, no issues in the summer or winter, your winters and summers are no different.

stop wasting time and money, hook it all back up the right way, and drive it,

check to make sure your head gasket is good, oil leaking down the block is the first sign your gasket needs to be replaced.

just checking but who where you reffering to that has a head gasket issue?

I don't even have my deuce yet, still waiting on my euc to clear. I was just working off the information posted previously by the person doing the electric fan conversion.

Does your friend run them on the highway with no fan running?

I want to do an electric conversion to reduce noise and parasitic power loss, not due to a cooling issue. I don't think any electric fan is going to flow more air than the mechanical fan that is sapping 12hp off the engine.

 

[rflegal]

I recall reading somewhere that one should ensure that the electric fan is shut off above certain highway speeds because the fixed rpm of the energized fan actually functions a a restriction. I think the idea was to allow it to "free wheel" above say 50 mph. Wouldn't it be simple to install a manual cutout switch in the dash and test?

 

[JasonS]

I recall reading somewhere that one should ensure that the electric fan is shut off above certain highway speeds because the fixed rpm of the energized fan actually functions a a restriction. I think the idea was to allow it to "free wheel" above say 50 mph. Wouldn't it be simple to install a manual cutout switch in the dash and test?

The airflow at highway speeds should keep the engine below the turn-on temp of the electric fan.

 

[oddshot]

The airflow at highway speeds should keep the engine below the turn-on temp of the electric fan.

I dragging this one up to see if there has been any new thought or experiences on this subject.

I've just done a bunch of searching and read both Deuce forums and ended up with about a 50/50 mix of opinions.

I read that the Deuce fan costs about 13 horsepower (+/-), and since I'm doing mostly driving on the 4 lane, an electric fan might give me a couple more MPG's.

Does anybody have any REAL experience with one? Good OR bad.

Size?

Cost?

Where at?


This thread indicates that : a pusher didn't work well ... but a puller just might. 3600 cmf seems to be the amount of air needed ... and two fans combined might be the best way to get that kind of performance.

BTW ... I DO agree with Jason that on the Interstate the air at road spped should be sufficient to cool the engine ...

BUT ... going up one of the long Georgia draggers ... well I can see the fan coming on to help out.



I do see that 12 VDC fans are cheaper than 24 VDC even if you include the cost of a 24-12 step down converter. Since the fan don't run unless the engine needs it ... and then it shouldn't stay on for very long ... I don't see a problem with the charging system.

I don't ever see me sitting with my truck idling for two hours.

I ran my MGB's with only a toggle switched electric fan for years. When I was racing them ... I never turned on the fan at all unless I was sitting waiting to go on the track.

But then ... a MGB ain't about 1800 pounds of hot cast iron LDT either. That's why I'm asking.


oddshot



PS ... thanks for the tip Gimp ......

 

[oddshot]

Oh yeah ... I ain't trying to cure anything. My truck runs at just about 180 ... maybe a little more when I get into traffic down by and into Marietta.

But the lure of maybe 1 or 2 more MPG's ...and ALL THAT EXTRA HORSEPOWER ... just sets my heart to racin'.

oddshot

 

[Kohburn]

I have the fans and the upgrade alternator all awaiting installation.

after a D turbo swap and an aeroturbine muffler, the fan and the transmission are the loudest parts of my deuce.

after this the transmission will be it and I have sound deadening, insulation, and carpet to help with that.

 

[steelypip]

One number I haven't heard from anybody. Is there a recorded CFM value for the engine driven fan anywhere? It would be sized for the worst-case Death Valley in July fully loaded with a loaded trailer case.

Most people with deuces woudn't need to match anything like number. But it is a useful yardstick to use when comparing electric fans to see how much cooling capacity you're giving up by the swap.

Oh, and always, always shroud an electric fan. You get flow reversion around the blade tips if you don't, which reduces cooling capacity much more than you'd think.

I am very surprised that a deuce needs active cooling in moderate temperatures running lightly loaded on a normal day on the highway. Cruddy cooling systems or water pump cavitation at high RPM might be causes.

 

[cjtroutt]

Ditto steelypip

 

[m-35tom]

seems to me the ideal solution would be a fan clutch but i don't believe anyone has ever found one that can be adapted in the close quarters provided. the rad 'could' be moved 1" forward maybe. anyone have any leads?

tom

 

[oddshot]

Oh, and always, always shroud an electric fan. You get flow reversion around the blade tips if you don't, which reduces cooling capacity much more than you'd think.

Makes sense to me ... I've always thought that the shroud was there to speed up the flow of air anyoldways.

How tight to the blade tips to you figure is the best?

oddshot

 

[steelypip]

Makes sense to me ... I've always thought that the shroud was there to speed up the flow of air anyoldways.

How tight to the blade tips to you figure is the best?

oddshot

Shrouding at low pressure differentials is not a big deal - if you're within 1/4" or so of blade tips you're fine. What you really need here is a plenum - that is, the shroud needs to surround the fan so that the air is pulled evenly over the entire radiator core before it's sucked out by the fan, and air neither stagnates over the core nor reverts through it. Basically you have to be sure that any air that tries to go through the radiator must exit through the fan. The bare minimum plenum would be a brake bent metal box with about 1" standoff from the back of the radiator core with the fan mounted in the middle with at least 1/2" standoff from the core. Have a look at any mid-70s American car or truck that still has its shroud for a good practical example of how to do this on a smaller scale.

Here's a typical aftermarket example.

As I think of it, it is quite possible that the lack of an effective plenum is one reason deuces with electric fans haven't fared better. On cars, such a fan usually covers one entire axis of the core. On thermosyphon engines like a Model A, the tubes run vertically and the electric fan is usually about as wide as the core is. On later low-profile cars the tubes run horizontally and the fan(s) are as tall as the core is. On many low-profile cars (think of a mid-70s Camaro), dual fans mounted diagonally are used.

In all these cases, there's a fan mounted behind every single core tube, so there's never stagnation over any tube and the water temperature at the outlet side will always be less than inlet for every tube. The fan plenum's purpose in this case is just to equalize the flow across the tubes so that they're all outputting the same water temperature to the outlet tank.

A deuce radiator is so blasted big that I suspect you have tubes that aren't getting any fan airflow at all unless you use a plenum. If 205 degree water goes into those tubes, it's coming out the other side at 205 as well, which isn't doing cooling a bit of good.

Consider dual fans (which would probably help with pulley clearance anyway as it got the fans off center) and a plenum.

 

[SasquatchSanta]

The reason the Deuce (or just about any vehicle) heats up at highway speed when you don't run a fan of some sort, is because air hits the front axle and other low hanging parts and builds a little bit of pressure in the engine compartment. That makes the air pressure on the front side of the radiator only a little greater than the back side, so not much are flows through the radiator.

What you need is an "air dam", something that guides the air more downward, under the front axle (thus lowering the air pressure in the engine compartment). I was thinking about a skid plate just for that purpose.

Seems I remember someone saying in a thread a couple of years ago that running with a winter front helped solve the problem you mention.

 

[ProviderDriver]

Just out of curiosity, what are the actual dimensions of the radiator? I work for a race shop and we sell Maradyne electric fans... I was wondering if two pair would fit? (For a total of 4 fans) Jones Machine makes pulley and bracket systems for water pumps, alternators etc, I have already talked to them about a triple alternator system for a deuce and they told me no problem. I was thinking 2 100amp 12v and a 60-100 amp 24v run off a single HTD or Gilmer style belt... The dual alternators work great on the race cars, was just thinking out loud...

 

[gaspain]

can someone please measure the space we have for this, so measure the radiator and how deep it is from the back of the radiator to the back of the current fan.

I'm 3000 miles away from my deuce right now, and am looking online for fans.

One thing to add; be sure to add an electric thermostat to kick the fan on and off. Get better mileage. Costs about $30

I did this mod to my BMW M3 a few years ago it cooled better and gave a few more horses, well worth the upgrade. Al vehicles should have this IMHO.