2nd Gen Non-Engine/Transmission Fanless

[Irontrader]

In reading the postings about the 5200cfm electric fan, I've noticed several people are running their Cummins without a fan at all.

For those running without a fan, have you noticed an improvement in your mileage?

I would think that Rams with manual trans could get away without a fan better than the auto trans since the auto needs cooling as well.

I've been tempted to try the electric fan route myself, but if there isn't a mileage improvement benefit I can't justify it to myself.

 

[illflem]

I've been fanless since Nov and it's hard to say if there's an improvement in mileage due to the effects of winter fuel and driving conditions. Considering how much quieter and warmer the engine runs there must be some improvement though. Take's power to make noise, right? I'm personally not considering an electric fan, it's easy enough to take the fan off and on. I will try keeping the stock fan off as long as possible though, I think it will be safe to 80° or more without the AC.

 

[Whitmore]

Iorn,I went fanless when my ram was almost new,I had a chance to run several tanks of fuel thru it before winter blend came in and I noticed an aproximate 1 mpg gain as well as it warms up alot faster,I still ran my lund cold weather front for 4 months,I just pulled them off as temps are getting in the 40's now #ad
kevin

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2001 eth dee,qc,lwb,3. 55,camper and tow pkg,driftwood,cummins e-brake,jardine 4" exhaust,dz alum checker run boards,bed rail,tailgate protector,better built alum checker toolbox with home made fuel tank under box,"CUMN" licence plates and captain vol fire dept plate too

 

[Deezal Man]

Hard to say, Between winter fuel, 265 snow tires, Sand bags in the bed. . 4wd in snow... driving @20MPH... traffic permitting.

I gave up trying. .

Has it been worth it? YOU bet ya!! I'm dreading putting it back on. I've gotten used to not hearing that darn thing.

Engine response is noticably snappier. Warm-ups are much better if I block 3/4 of the radiator.

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98. 5' 24v 2500 Auto/3. 54 4x4 SB QC 285-75-16's on Alcoa's. Everything but leather. PIAA 1200's, AMSOIL dual filter relocation system, Smittybuilt Stainless Steel Nerfs, Rhino Liner(Junk), K&N air filter(For Sale)15 year AMSOIL dealer. Time permitting, Soon to include Ultra-lite Pyro,0-50lbs boost, Trans temp in the pillar. Rancho 9000's with in cab adjustment.

 

[HEMI®Dart]

My mileage went up about 1 mpg, even with the crappy winter fuel after I took my fan off.

I'm with Deezel Man, I'm dreading putting that thing back on.

I block 95% of the radiator to build heat into the coolant. This is a 12 Valve engine.

Engine gets to operating temperature in half the time, much quietier, and it feels like 25 hp increase.

I agree with illflem. I'm going to try to run fanless into early summer. Maybe all summer. Can't use the A/C though. No big deal. 5 speed truck, no auto to keep cool.

The increased mileage, No fan noise & power increase is worth having no A/C. #ad



EGT and intercooler effectiveness and intake manifold air temp will be monitered in warmer weather with no fan. #ad




[This message has been edited by HEMI®Dart (edited 03-15-2001). ]

 

[illflem]

Now that Hemi mentioned it I should say that I do have a temp sender mounted in my intake manifold just up stream of the manifold heater. With the fan it usually reads 20-30° above the outside temp,without the fan it still reads the same while moving, but if I stop it will shoot up to almost double the outside temp, I've been trying to keep the intake temp between 60°-90° with winter front, drawing underhood air and blocking the inter cooler more, worked great when cold. Now that it's warming the intake temp might be something to be more concerned about than the coolant temp, I know 90° is about the top end for engine efficiency, but am not sure how high of temps can be tolerated or if it even matters. Just something else to watch for when going fanless. Now that I think of it an electric fan may be the way to go.




[This message has been edited by illflem (edited 03-24-2001). ]

 

[drawson]

I have also been fanless since Nov. last year. My milage has increased . 92 MPG overall. I am going to be electric here soon. I already has one fan on the outside to the right side over the A/C condencer and have an 18" Perma Cool for inside that I'll have on here as soon as I get the mounting worked out. The inside fan will be wired to a thermostatic switch and a manual over ride. The outside one is already wired to come on with the A/C and a manual over ride.

The only time it has been used this winter is to aid in cutting down shut off time at home.

I would not want to go back to the clutch fan. I really like the lack of noise and response w/o it.

 

[HEMI®Dart]

illflem,
Running on the highway or around town shouldn't produce high intake air temperatures. Just guessing. Its the high boost PSI/ High RPM runs that may heat up the intake air. Whether the intercooler, without an engine fan can reduce these temps would be good to know. The air passing thru the core at 40 mph may be enough to do it. It cools the radiator fine.

My '94 Dodge/Cummins Turbocharger Familiarization booklet says at high boost levels, intake air temperature of 220 degrees is not uncommon. I don't know how true this is. I have never burned my hand on my intake horn. #ad


Drawson or illflem,

Do you have a Infared Thermometer? This would make temp measurements a breeze. We could compare Turbo compressor outlet Air temp to intake horn temp ect.



[This message has been edited by HEMI®Dart (edited 03-16-2001). ]

 

[drawson]

Hemi, I do have a infared thermo and last year I think Bill(illflem) installed a temp sender in the intake. Last summer I did some playing with my IF thermo and found that the inlet side of the intercooler got up to 210 deg and that the intercooler is good for a drop of about 115 deg. I also know that the electric fan I have on the outside of the A/C condencer does speed the cool down when I get home. I have it blowing on the inlet side of the condencer and intercooler. I really believe that the electric fans will help more at low speed because they are running at a higher RPM than the factory fan does at idle.

[This message has been edited by drawson (edited 04-22-2001). ]

 

[Joseph Donnelly]

Sickly got his 609 hp with the stock fan. I wonder what he could do without all that drag holding him back. #ad
I guess it's too bad we want to keep that old farm truck in street trim [if you have seen Sickly you understand why folks might have thought it a farm truck at the Dyno Day--muddy, dirty, nasty gray homemade bumpers, etc. ] I thought about the Horton fan but that is expensive horsepower, so the fan is still stock #ad

 

[illflem]

My readings with the IR thermo are similar to Dee's around 200° pre cooler right after a run at idle, about 70° post cooler. The highest temps I've seen in the air horn are always stopped while idling, fan or fanless. The temp will drop rapidly when I start moving fanless, or just hit the throttle with the fan, highest temp I have ever seen is 122°. The horn temp seems to dependent on outside temp more than anything else. Pulling a trailer up Cabbage Hill grade in Jan I had my boost at 20+ for at least 10 minutes, the intake temp stayed at 70°-73° the entire time, but it was getting colder as I climbed, rain changed to snow. On a recent 60° day my intake temp climbed into the upper 80s while cruising(65 mph), I removed 2 panels off Lund front, temp dropped right back down to low 70s while moving, this was fanless.
Never in all this time has my coolant temp gone over 190°, in fact it most always runs cooler than I'd like to see, even fanless. I am almost positive that unless you are towing on a hot day uphill or stop and go rush hour traffic that an 18" electric fan will keep all the temps safe. We'll see soon, I plan on keeping my fan off for as long as possible. I bought a 18" electric fan from the junk yard ($25) a couple of years ago for a hydraulic cooler on a piece of equipment, draws 8 amps and blows like hell, I'm going to look for another one. One thing I learned from installing this fan is that it must match the cowling for the most effect, the downwind outlet must be smaller, it creates a venturi effect. Might be something to keep in mind when shopping for an electric fan, make it the same size as stock for the most effect without having to alter the shroud. -Bill

Joe, if you get Sickly off the dyno and out on the road with 600+ hp that stock fan may just pull you along enough to break 150 mph!!! #ad

 

[icarus33]

Here are my Fanless results:

Fan On:

8 fillups prior to removing fan 8/21-11/27
Still with some non winter fuel.
Included a Vegas trip with mileage @ 18. 5 both ways, camping trip pulling a popup, otherwise city driving at 5K feet.

15. 98 mpg

Fan Off:

8 fillups 11/27-present
Some fishing trip highway miles

17. 16 mpg

So looks just a bit over 1mpg for me AND running all winterized fuel.
I'm also not looking forward to putting the fan back on. 50 degree days idling in heavy traffic is getting the temp up to 190-200 until some air starts flowing again though so it looks like it'll be time to switch back soon.

icarus

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'98. 5, 2500, 4x4, LB, QC, AUTO, 3. 54 rear, Snugtop, Rhinoliner, ISB, non Cummins enhanced ECM, DDIIIa injectors, Transgo Diesel shift kit, KJones TC, Autometer boost, transmission temp, digital pyro, Mag-Hytec diff/transmission cvrs. , Redline lubed.

 

[Rambling]

Can anyone translate 1 mpg into hp? I don't mean what the factory specs might say. How much weight would one have to remove to get 1 mpg fuel improvement or add to lose it? Another way one might look at this is how much weight change would improve/lower the available hp (can we say Faster/Slower?). When looking for the best trap times, it would seem every bit of hp one could squeeze out would be helpful.

Just a thought.

 

[The patriot]

I had my fan off most of the winter.
I found that 60 degrees is about the limit with the winter front on. This is empty, not towing anything.
I fugure when I remove the cover, it'll be good for another 20 degrees or so.
Eric
BTW I saw at least a 1 MPG inc. in mileage.


[This message has been edited by The patriot (edited 03-17-2001). ]

 

[tom sweeney]

well,i finally did it... i removed my fan just today!!!... it sure is a lot quieter without it,seems to wind-up much smoother.
i'll have to wait and see about the mileage,i'm convinced that an electric fan is the only way to go... now to find one!!!
i'll post mileage results as they become available... . tom

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2001QC 2500HD LB ETH/DEE 4x4 4:10's LSD, Pacbrake,Combo Gauge on A pillar,All options except cab lights,Xcelerator air filter,Forest Green/Light driftwood. Westin tubular black powder-coated side bars.
26'Holiday Rambler 5th wheel. Extra Class Amateur Radio Operator ke3Rx

 

[Vaughn MacKenzie]

Normal driving around town with temps in the 60s quite a bit the last few weeks, no problem with temps.

HOWEVER, I got it too hot today. . . I was driving around on some rough dirt roads and after 10-15 minutes of this I looked down and saw my temp at 200F. This was running mostly at 5-10mph and in first gear, sometimes second. It was mostly flat, very little engine loading, EGTs under 400. The temp continued to climb so I turned the heater on MAX. By the time I got back to the main road I was at 215-220 (line between 190 and 240, so I'm guessing 215). It quickly cooled off to normal once I got above 30mph.

This was a situation today where a fan would have been necessary to maintain temp. Obviously it was a lack of air movement that was the culprit. It was around 60-62F at the time.

As far as fuel mileage, I saw virtually no MPG improvement after taking out my fan last November, however the engine revved more freely at higher RPMs and seemed more effortless driving. Nice noise reduction too.

Vaughn

 

[drawson]

I got my inside electric fan installed today. I have it hooked up with an adjustable thermo switch as well as a manual override inside. I also wired a light inside the cab to tell me when it comes on. i have the thermo switch adjusted at 180 deg and did quite a bit of driving around today (68 deg outside). The fan never came on at all.

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EAT'M UP
97 2500 Club 4X4 3. 54, Forrest Green/Driftwood, LSD 5 speed, & Psychotty Air System, TST #11, 370 HP injectors, timing at 16 deg. , 16CM2 housing, AFC spring kit, TST EGT gauge & 0-60 boost gauge in A Pillar, Cat-be-gone, 4" Dynomax Bullet muffler, Crome 4" turn down, 2 Electric Fans, One inside/ One out front, AmsOil Through out, Geno's trans filter kit, AmsOil Bypass system, Lund Winter front, Leer Cab Level Shell Driftwood , 255/85R16, South Bend's Hypo Clutch*NRA/USPSA member and proud of it*

[This message has been edited by drawson (edited 03-23-2001). ]

 

[illflem]

Dee, how about the AC, will the fan come on automatically? Where did you place the
T-stat? I don't know a lot about AC, is a fan necessary only when the rig is not moving?-Bill

 

[drawson]

Bill, I haven't got it set up for A/C yet but both fan will run anytime the A/C is on. The Thermo stat switch portion goes right into the radiator tubes. (Kind of micky mouse) I have it right next to where the upper rad hose goes in the radiator. I manually turned then on and got the temp to cycle up and down just as it always used to with the OE fan. Tomorrow will be the big test I am moving my brother in laws back hoe.

 

[illflem]

Beware, I stopped to talk to someone today 70° and fanless idling, thought it was only going to be a minute but it turned into 15, intake air temp was 235° when I returned, coolant temp was normal. Took about five miles at 60 mph to cool the intake back down to 80°. I recomend that anyone running fanless or with an electric fan install a intake temp gauge, it's simple. I just used a digital AT temp gauge and tapped a hole in the intake horn for the sender. Think our problem is going to be the inner cooler not the coolent.

[This message has been edited by illflem (edited 03-24-2001). ]