[AZdiesellady]

We are contemplating doing the switch for more air/engine cooling...anyone done this?

Thanks for your insights.

AZ

 

[Joey D]

You are going to get a lot of it won't work reply's, you may get a few it will work reply's.
My take is use 2 Ford Taurus or Lincoln Mark 8 fans and it will work. They flow 4500 cfm each. You need to make a shroud and have it wired correctly using hd constant use replays but i say it will work.
i have 2 in the garage to install on my truck some day.

 

[edzzed]

One point to mention, With the stock setup. If you tow your temps will rise until you hear the whoosh of the fan clutch locking up. At that point most will see the temps decrease. Takes some serious hp to spin a stock fan clutch locked up. If you plan on towing I doubt the electric fans will be enough. If you just commute here and there, Well it'll probably work till you have a seriously hot day out. Then you can fill us in on how it worked. My thinking is can you tell me why no V8 trucks come with electric fans cause I can give you many examples of cars and suv's that went electric. Maybe a larger rad in our trucks would help but I think truck makers build engines and match them to sufficient sized rads to provide adequate cooling under normal circumstances. Going under that thresh hold might mean warranty work. It could also come down to fan clutch installation is cheaper than electric as a cost measure, I just happen to think it's the other way around which is why most cars these days have electric fans. It's not cause they cool better, It's cause they're cheaper to install.

 

[oil pan 4]

I have been running electric fans for 4 years and now problems.
I even do a little towing.

 

[outalne94z71]

I have been running electric fans for 4 years and now problems.
I even do a little towing.

you also have a better body for cooling, the gmt 400 trucks have terrible air flow so they run hot

 

[THEFERMANATOR]

you also have a better body for cooling, the gmt 400 trucks have terrible air flow so they run hot

No kidding. The grill opening on my BURB compared to my 01 donor truck the DMAX came out of is ridiculously small. I have trouble keeping the DMAX cool in my bURB when towing heavy on a hot day whereas guys in 01+ trucks won't even hear the fan clutch come on.

 

[oil pan 4]

Between the electric fans and water injection I dont have any problems.

The front end aerodynamics are all messed up on 2wd trucks, before the turbo install is finished I will try and iron them out.
The opening for the radiator is only 15x30 inches, I opened mine up a little back in 2008 going to do a little more or maybe a lot more this time around.

 

[AZdiesellady]

We use the truck to haul our 2 horse trailers....very little commuting, trailers full run 12k and 8k. There are some steep grades that we run...6% for about 6-7 mile stretches. Now that we have fixed the turbo, she runs a lot better but we still get to the dreaded 210* at about the top of the hill. Infact, we were hauling back home last nite from Flag, going up a 7 mile, 6% hill, and she got 'hot' at about the last mile. Once at the top, she cooled down. Air temps outside were in the 70s.


We are in AZ so temps are HOT in the summer/fall...

Would water injection be a better option? Thanks.

 

[oil pan 4]

You can try a water injection system or try buying $21,000 worth of high flow coolant pumps, durmax fans, 180'F durmax fan clutch, some over priced T-stats and what every else they say you need to cure the over temp problems the 6.5L has.

Read privetpilots water injection thread, I added every little detail about my DIY water injection system on there too.

http://ecomodder.com/wiki/index.php/Water_injection

 

[57diesel]

I think one of the issues with electric fans is a couple of small ones don't work as well as one big one and one big one is just not practical. Building a big electric fan with a big motor and its needed support structure would be expensive and take up a lot of space. You then have to power it. I have heard that a truck sized fan can require in the 5 hp range. Im too lazy to do the theoretical math but I am going to guess a 5 hp motor at 12V is going to be over 100 amps so we are talking about some big wires, a big solenoid, and what another alternator?

An interesting trend in heavy equipment is hydro stat driven fans. Not practical for our trucks since we don't have much of a hydro system but would seem like something that could be designed into them say an extra module on an Allison trans? They are apparently computer controlled so they can run (or not run) at any required speed. They can even reverse direction to try and clear a blockage if you operate in an environment with lots of big stuff floating around.

 

[Tommygunner]

We are contemplating doing the switch for more air/engine cooling...anyone done this?

Thanks for your insights.

AZ

Your stock 1999 fan flows more air than any electric fan on the market. You wont cool any better by going electric. With the weight you tow I would look into water mist injection. The only advantage electric fans will give you is maybe a little better fuel MPG.
Someone mentioned Tarus fans. They do flow a lot of air but they use quite a bit of power. Running one fan uses 30 amps. 2 will double that. Startup amps are usually around 60 amps on a single fan. 2 fans will put the startup amp draw more than the stock alternator puts out. Add lights, AC, and other power needs and you will need a bigger altenator.
Flexalight makes A set of electric fans for Dmax. They flow 6000 cfm. Only draw 37 amps. From what i have read they do work ok and people report better fuel milage. But they cost around $550.
You can do WMI for less.
Also take into concideration that you have a oil squirter engine. The engine uses oil to help cool the pistons. So you need good air flow thru the oil and trans coolers too.
IMO you should stick with the stock fan. add WMI, Do a flush and fill, add some water wetter, and make sure your cooling system is clean and in top shape. Your radiator may also be getting plugged up. Might be a good idea to pull it and have it boiled and rodded out

 

[edzzed]

After thinking about our upcoming camping trip and past experiences, Having to turn the heat on during long hill climbs. I bought this http://www.ebay.ca/itm/390446992532?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 Cost was 123.18 Canadian, Sorry you all down south have to pay 124.82 since our bucks worth more. What's worse is Canadian Tire sells the same unit for 325.00 + 12% tax. Geez, what crooks. Anyhow as a small test I started the truck cold , let it run 2 minutes and shut it off, The original fan clutch came to a quick stop. I then swapped in the severe duty Hayden and did the same test. The fan stopped so fast it actually went in reverse momentarily. Kinda like slapping your hand against an imaginary surface. You'll notice it comes back up a wee bit. With the new fan clutch I expect I'll be able to keep the A/C on during those long hills. Time will tell. I'll post the answer in OCT.

 

[Joey D]

What CFM does the stock fan pull? The other issue is the fan does not come on until the motor is hot. I have the hayden clutch on my 6.5 and it has almost as much of a delay as the GM unit did.

 

[deekster_caddy]

We are contemplating doing the switch for more air/engine cooling

Mechanical fans will always pull more air than electric fans. You need to get things really hot to verify if your fan clutch is really working or not. My guess is one of three possibilities - 1) that you haven't got it truly hot enough to engage the fan clutch, or 2) the radiator is clogged with debris or 3) you have a bad fan clutch.

The hard part is that there is no consistent temp number that means the fan clutch is going to engage - it's based on the air temp leaving the radiator, and that depends on more variables than just the coolant temp in the engine.

If you are towing your load up a long grade and the coolant temp is getting 'up there' you should hear a jet engine fire off under the hood - that means the fan clutch engaged. If the temp just keeps climbing, you may have a bad fan clutch.

disclaimer - I'm not a diesel guy, but I've been around the block trying to cool big blocks doing hard work and found mechanical with a good clutch and proper shroud always wins out over electrics.

 

[57diesel]

I just put a new clutch in one of my cars and really notice the roar on a hot day. I thought it worked fine before, it really seemed to move air but now it really moves air when it get hot.

 

[oil pan 4]

The only advantage electric fans will give you is maybe a little better fuel MPG.

I picked up 2.2mpg on my belt fan delete.

I have heard that a truck sized fan can require in the 5 hp range.

When going from my stock fan "free wheeling" on the high way to not being there at all and gaining 2.2mpg that tells me the free wheeling fan was using about 4 to 5 horsepower.
I about a year ago I was reading that the "dinosaur fan" upgrade used 49 horse power at full speed when engauged.

 

[Tommygunner]

disclaimer - I'm not a diesel guy, but I've been around the block trying to cool big blocks doing hard work and found mechanical with a good clutch and proper shroud always wins out over electrics.

X2
I have tried to cool BBCs with electric fans to hopefully save a few MPG. No work so good. Fine if you did not have anything heavy hooked up to it. But put a load on and the temps climb.
I would never trust electric fans to cool a turbo 506 block 6.5. Thats why my truck has mechanical with a hd fan clutch.
Yeah you can get away with electrics with a non turbo engine like Oil Pan has. But for a 6.5 TD towing 10k pounds mechanical is the only way to go.
If MPG is your goal and you dont tow much. Sure you can go electric fans. But if you want to work your truck hard they are not up to the task.

 

[honey_badger]

ever considered using a horton ec450 electric fan clutch? i've priced them out, they're around $450. seems like the best of both worlds. come spring i'm going to have one installed in my truck

more info here:

http://www.ngclark.com.au/products/horton/fan_clutch/ec450.htm

 

[oil pan 4]

I wouldn't try electric fans for heavy towing.
I towed 6k afew times when I first got the truck in 2006 and never have come close to that since. Most I have towed since was about 2k (single pallets of shingles) and it was on 45mph primary roads and 1k plenty of times on the highway.
Also do a lot of driving with the trailer on there and about 600lb of tools in the back of the suburban.

Im turbocharged now but not with any POS GMx serries turbo.

A compromise might be to run a big electric pusher fan and pull your belt driven one off and put it in your big heavy trailer or tool shed, if say you only tow heavy a handful of times each year.

 

[PrivatePilot]

We use the truck to haul our 2 horse trailers....very little commuting, trailers full run 12k and 8k. There are some steep grades that we run...6% for about 6-7 mile stretches.

On those sorts of grades, with the 12K trailer you WILL overheat with just electric fans. You probably will with the 8K as well. People that have done the electric fan conversions often pull small trailers on flat land and have never experienced a super heavy load on steep grades...they just don't work well on a 6.5.

When was the last time you pulled the cooling stack and cleaned it all?

Yank out the rad and get it spotless. Remove the fan clutch and scrub it, especially the bimetal strip that controls engagement. If you don't know what thermosts are in it, replace them with AC Delco.

That alone will help immensely.

Beyond that, if you're just hitting 210 but not surpassing it, well...no need to worry that much - you're still safe really, it's only *past* 210 that it starts to become concerning. If it's a slight touch over, turn on the heat full blast and open the windows while climbing the grades - it helps a lot as well.