Possible cooling options for the 6.5 [Archive]

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Robyn

07-10-2007, 16:07

I have been working diligently on the idea of having an electromagnetic fan drive assembly that will allow for a more positive and controlable cooling fan our 6.5 trucks.

I have spent many hours this week on the phone with various companies in search of some good hard concrete answers.

As it stands right now there may very well be something good in the wings just about to spring forth.

I have some folks to meet with this afternoon yet to look at some parts and to do some measuring.

What the plan is, is to have an electomagnetic clutch fan drive with a 20-21 inch plastic 10 blade fan.

The setup will work in conjunction with the dual Tstat setup, the high capacity water pump and then have its own wiring setup that will turn the fan on at around 195F engine temp or will turn it on if the AC system pressures require fan operation.
The system will also have a manual overide switch to allow the driver to select fan on and just leave it run for those tough pulls through the hills or for slow traffic where max cooling is needed to assure good AC operation.

This is not new technology by any means but rather just adapting good sound ideas to our 6.5 trucks.

The industry has forgotten the 6.5 for the most part so not too many companies really care about doing development on anything for it.

This project is still in the development and sourcing stage.
The parts are starting to look promissing but I am not flying any flags just yet.

I know that the towing community can really benefit from this setup.

Let me know what you think of such an idea.

I am going to plow on with it though even if its just for my truck alone as it will eliminate soooooo many heat related issues that cant be addressed any other way.

let me know

Robyn

stingthieves

07-10-2007, 17:32

Would it not be much more fault tolerant and simpler/less expensive - to pay Kennedy for his corrected fan clutch and big fan to go on the 97 newer water pump - Its a kit!

Buy a chip yet?

mkhagemann

07-10-2007, 18:12

built one about six years ago for for my 95 C3500HD service truck. a little tight on space, had to run the fan about 3/4" closer to the rad. I used a 205 deg switch with a over ride for PTO operation. eventually clutch needed replacing and went back to a thermo clutch with a Griffin Rad. the all alum Rad had 1.25" tubes instead of stock 1" tube. made all the difference, no more heat problems even with stock fan. Keep in mind my curb wt is 15K all the time with an ocasional 10,000 lb tag a long, Georgia summers sometimes 95 with the A/C blowing, 4 deg hill, never over 210 deg water temp!

1995 C3500HD NV4500 latest Gen Engine, turbo, intercooler, chip, lower comp, ect
1996 C3500HD 4L80 stock

Robyn

07-10-2007, 22:32

I come from big truck background and still do it every day.
I hate goooey drive fans with a passion.
The clutch unit in my Western Star has been in there for 540K now and its still the original.

This morning I got in the truck and as soon as I lit the fire in the Cat I switched on the AC and then set the fan to manual operation.
I yanked four loads over a 10 mile stretch of 7% grade at a temp of around 100F and I was grossed at 105,500 Lbs the engine never went over 180F which is the T stat rating.
I'm sure that windmill out front sucked in every bug for 5 miles. :D

This is what I want to see on my "Little" truck
I want to be able to turn on the fan and leave it on or to be able to let it manage itself in the more moderate to cool weather.

The project has taken a turn in a slightly different direction though.
The supplier was not able to supply a fan clutch that will fit a counter clockwise rotation. (They promised me they had one in stock) ya sure :eek:

There is however a small air unit that will bolt right on to the exisiting hub and go to work with nothing more than a small compressor to provide the air to run it.

This unit is also repairable with available service kits.
The electrics are throw away and cost $500 approx

This is going to be doable and I see no reason at this time that I cant get it up and working at a very reasonable cost.

Along with a Dmax plastic fan this should be sweet.

Truck has a chip now, its an early one and not sure who made it though. They were not proud enough of their handy work to leave their name on it.

My goal is to be totally in control of the fan at all times.
The viscous drive (even JK's) will not pull near as much air at low engine speeds as a direct locked fan. The Viscous drives are rated at 80-90% of shaft speed during full engagement and not 100% and this is at speed.
The rated speed at idle I am not sure of but its going to be lower due to slippage.

We shall see.

Robyn

My 95 has an AC highside pressure switch that I believe is used to speed the idle up during very hot conditions.
There is a high pressure shut off on the AC pump as well.

j_k_auto

07-10-2007, 22:48

I always hated the fan clutches on any car or truck. I know what you mean by the air clutch fan. I run a detroit with the same on off switch and I never figured out why they do not put them on smaller diesels. $$$ probably. I am still thinking aout electric fans (2) in a shroud but not sure if it will pull enough of cfm. The reason behind the electric is there is no cfm loss why climbing a hill and you loose no power either. Plus you never hear the fan roar. I always hated that in my big truck esp while the ac is on. It never shuts off.:(

Robyn

07-11-2007, 08:34

Its mostly about cost.

I am running into the $$$ issue now big time.

The electric units were $485. The air unit I found from Horton that will fit with minimal bother is $2000 :eek:

I am going to continue to look for a used unit that will do the job.

My original intent was to come up with a solution that could be marketed as a kit ready to install but I think that's a lost cause due to $$$

I am going to persue this as a one off for my truck though.

ARRRRRRRRRRRGGGGG

Robyn

Shikaroka

07-11-2007, 08:35

I have been working on this a little too.
I have a couple parts laying around that I have been toying with, in my spare time (which ain't much)
I think this may be the way to go, especially for helping the A/C work better.

I wish I had a spare DMax fan to play with, then I would probably be testing it out about now.

damork

07-11-2007, 14:04

I work in hydraulic development and spent for 3 years in applications of hydraulic fan drives. Modulating fans are great, they really help eliminate the shock an instant on fan system can bring to belts, components, etc.

I've considered coming up with a modulating hydraulic fan on my truck as well, but each time the cost factor comes in. I know a few Grand Cherokees came with factory hydraulic fan drives (I know those who were part of the development), but haven't looked closely at it.

Several transit coaches used at airports and high end luxury buses use hydraulic drives where steering gets priority flow and the cooling fan gets the rest. It works very well and the fan is truly off or minimized when cooling is not needed. Some of those coach companies are or were in the Eugene Oregon vicinity (Monarch-Magnum Safari-Country Coach) and might be worth looking at for ideas.

mkhagemann

07-11-2007, 14:15

When i built mine i used the parts from the "Cyclone" developed for the Ford 7.3. Unfortunately the 6.5 doesn't have the space of your 18 wheelers, so the clutch is small. The way "Cyclone" (horton clutch) gets its lifespan is to raise the switch temp to about 220 on and 195 off, this will limit the cycle times. I like most of you wanted manual control for PTO and a much lower on temp for auto control. The problem is it shortened the life span. If the idea is something anyone would like to pursue I would be glad to email info on fan part #s and show the adapter i had to fab.

1995 C3500HD
1996 C3500HD
email: mkhagemann@msn.com

oldmechanic

07-11-2007, 15:44

the military humvees used a hydraulic clutch that used engine oil pressure that worked pretty good might want to look into that

Cecil

Robyn

07-11-2007, 16:06

An oil pressure actuated fan clutch would be sweet.
I am not sure though that the assembly will work with the serp belt system. (Military stuff is V belts)

I have gotten off onto a new idea. The air actuated clutch from Horton was just too spendy and the folks at Horton seemed to care less about anything other than "call your dealer"

Things in this country have gone from "CAN DO" to DONT CARE

BUTTTTTTT there is a light at the end of the tunnel. The Ford Stroke has the same size water pump shaft as the 6.5 and the hub from the stroke pump is threaded and there is an electric clutch that fits that application.

The local water pump rebuilder said he would happily swap the flange from the used up stroke water pump I got onto the fresh HO 6.5 pump for a grand total of $30 labor.

This will make life real easy if this all works.
I have to sit down and look the GM pump over and do a little more measuring.

The water pump pulley is going to need a trip to the lathe and the pilot hole opened up some to fit the PSD pilot flange.

All this will be easy and the actual adapting will be just a matter of swinging some wrenches and doing a little wiring.

Navistar uses the Horton electric clutch on the T 444E in the business class trucks so it will most likely be around a while.

The nice part is that this conversion does not require butchering the truck and other systems to make it work.

All is looking better.

Later

Robyn

mkhagemann

07-11-2007, 18:44

Robyn i think we're on the same page. The "Cyclone" fan clutch i adapted was also for the FPS. Built it over six years ago. I'm guessing your going to use the Ford fan, get it from a gasser (20")it fits the shroud, the FPS fan is about 27". The problem i experienced is the fan off-set moves the fan closer to the rad. The only difference in your method and mine is i made an adapter to mount between the clutch hub and original fan pulley. This way one doesn't have to remove their WP to install it or modify the pulley. the adapter use a .375" flange with the 1.25 threaded boss and mounts just like the old fan clutch. If a fan can be modified with a little more offset to fit closer toward the engine about 3/4" it would be sweet. just remember i still think the larger rad I keep talking about would solve everyones cooling problem much better and requires ZERO modifications.

Thanks Mark
1995 C3500HD
1996 C3500HD

Shikaroka

07-11-2007, 20:10

just remember i still think the larger rad I keep talking about would solve everyones cooling problem much better and requires ZERO modifications.

Hey Mark,
I've heard you talk about the thicker radiator. Do you have a part number for this beast?

Kennedy

07-11-2007, 20:31

Robyn

07-11-2007, 20:35

Mark

The issue now is that Horton has discontinued a lot of clutches.
The CCW rotating units are limited to two. The serp belt system just locks this whole thing into a CCW rotating clutch.

They used to make some nice little air clutches too but no longer as the market has dried up.

The T444E Navistar is the only unit that uses a Horton and they use the electric one.

It has a 1.25"X18 RH thread.
Luckily the GM and Ford pumps both have a shaft diameter of .4455" and the flange is workable.
I have to modify the water pump pulley to pilot onto the hub from the stroke plus drill new holes (maybe slot) to allow the bolts to work.
The stroke has slightly larger bolt holes in the flange.
The GM still uses the SAE studs on the water pump and the Stroke has metric.

No biggy here though.
The offset will be about 3/4" deeper into the shroud but that wont hurt anything.

Not sure whos fan Im gonna use yet. May go with a Dmax depending on the bolt cirlce.
The fan pilot is 5" on both the GM and the Horton and the Horton has 6 studs.

I want to go with a plastic fan and loose some weight and maybe pick up a blade or two.
The stock GM fan is 19.5" and anything from there to 21" is fine by me
The steel windmill is bloody heavy.

Later

Robyn