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HMMWV Hydraulic Fan Clutch complete setup for all 6.2 and 6.5

Cleaner than my engine at the moment... Coolant, oil, trans fluid, and diesel everywhere from recent work...
uniquediesel said:
Here is a couple pics of the setup. Please excuse the dirty engine as this is being tested on my beater driver.
Click to expand...

This is a dirty engine. It went to the scrap yard along with the OEM 6 bolt fan clutch that was it's demise. Even the underhood lamp is coated in oil.

splatter1.JPG

splatter2.JPG
 
Update...

I've added it up and found out a few things. Like I've been mentioning this isn't a cheap undertaking, but it has many benefits not found in current offerings. This is also not something cobbled together either, it will be a real professional product.

I will be ready to post a price after capturing some video of it's operation and some images of the setup.

This setup can work in three modes. On, Off, and Automatic. It will work with AC for proper operation in Automatic mode. The clutch is gentle at high RPM engagement so no worries about belt or premature crank pulley failure as a result of running this.
 
I realize you are working on a complete kit, which is a great idea for the trucks. I am interseted in only the fanclutch with a serpintine belt pulley, as i already have the correct fan (hummer used same as hmmwv) and i will drive mine of air instead of hydraulic as i have air on mine in abundance. I have no ac system to worry about. And I will have to make a custom lengthy line from my air valve to the hub also.

My only concearns are 2 items:

#1--if there are different drives, spin on vs 4 bolt water pump. The 4 bolt HO puts out the same volume, but the spin on is the balanced flow. Can you get both versions, or just the bolt on?

#2--price.
 
Honestly, I think this whole "spin-on" water pump stuff is complete hear say started up by Bill Heath; the king of not backing any statement he makes up with proof.

I'm only going to support the bolt-on pulley version. There is enough material in my pulley to thread it for a thread on version, I just don't think that it's worth it to make that version as well. Plus making it screw-on ensures the pulley can't be used for anything else. The two bolt-on versions can be modified to replace one another.

Spin-on Fans are a complete joke in the industry, every mechanic I know hates the design and sees absolutely no reason why it's better and the industry made the change.

I'm old-school in that if it ain't broke, don't fix. Never seen a problem with a centered hub and 4-retaining bolts.

#2 Price. I have a figure of what this all costs. I need to generate a little more interest in people seeing the actual application of this fan clutch system so they can appreciate how well it works, then sit ya'll down and talk about price. I daily drive the truck with this prototype setup on it daily and I think (and others that have seen it) that it's the neatest thing.

I'm finishing up the A/C controls is my last piece.
 
Actually cooling improvements is one of the only good things to come from, or should I say documented by, Heath: full article below. (No, I am not a fan. But credit is due. You decide how much.)

It's got nothing to do with 4 bolt vs. spin on. It's the updated pump design that happens to be spin on. So did they ever update the older 4 bolt replacement pumps? They = anyone including aftermarket.

I have had 1995 gas 350's with the balance flow problem that would boil the passenger side while the driver side was in the normal range. The GM dealer knew the issue - replace water pump. So maybe this was a 1995 only problem.

On 6.5's I use new 4 bolt HO water pumps and they take everything I could throw at it with the low temp fan clutch, single t stat and the 1998 or Duramax fan. So I am also a skeptic, but, never measured the passenger side to compare to the driver side.

http://www.maxxtorque.com/2009/09/heath-diesels-65l-diesel-heavy-duty.html
 
I am not a fan of Bill Heath, nothing for or against him. He did not invent the spin on water pump for this engine, he learned of it. He purchases, removes the badging, marks it up and sells it. He quit selling the kit with the two hoses at the back of the head that he was making profit from when he learns the truth.

GM engineered it and produced it at an expense to their profit. They did not release a ton of information about it because they were avoiding a recall. By offering it as a new model upgrade, and being able to replace any units under warranty to the new system they were able to avoid the recall, standard industry practice. The water pump itself is a GM fix not a Bill Heath fix.

Using a better fan and better fan clutch system can make up for some of the difference in the balanced flow spin on water pump, and the high output bolt on style water pump. GM did the testing on this as well. GM opted to correct the problem with the pump reengineering. They went to a spin on for all the reasons they listed in the info they (GM) put out years ago.

I'm not trying to debate this, and I am interested in purchasing from you. I would prefer the spin on pump as it is better per GM. I am willing to buy the clutch it up from you if your price is not way over the other suppliers, in order to support you, because you are a vendor on this site. There are tons of them available online new and used. The rebuild kits are available from multiple suppliers. I am only waiting in an attempt to support you for becoming a vendor to the site.

If after using it I later decide to add the spin on pump I can machine my own adapter if you do not offer it.

I'm just waiting to hear your price on the clutch, I have the correct water pump and fan for this HMMWV clutch in place- let me know.
 
In regard to the spin on clutch pump. I still see no proof whatsoever that the pump moves more water. None the less how the stock pumps and it were actually measured. There are figures posted in the article but they not backed up with any kind of method.

I'm going to go ahead and kill this thread.

I'm not trying to be competitive on this product because the parts are extremely expensive and I have to have some margin for when committed to building a kit that I can get all the parts for my predicted costs, not take a bath on some of them.

This kit will be $2,100 with every part.

I know this is going to get a lot of big eye balls.
 
As far as i know there isn't another vendor or seller anywhere that offers this setup as a fully bolt on kit or any other way. Also I don't know of another seller that has any of the parts needed to build the setup or has done the engineering & testing & R&R for a kit like this for our trucks to be able to back such a thing with a Warranty , yes the Military uses them for a reason I would think, if a electric clutch was close to being as good do ya think they would be using one ??
 
Even Kennedy Diesel responded to demand and now offers both 4 bolt and thread on low temp cal fan clutches. Maybe in the future you could offer thread on if there is enough demand.

We had a thread on here years ago with photos of each pump. The Passenger side had a bigger coolant channel on the thread on pump.
 
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I understand the desire for the spin-on. If someone wanted one right now I'd make it for them.

This can be a kit, or a build to order type of thing. At present this price is set. Just like anything else one-off, every time it's built it get's more expensive and the price would be set after everything is built.

It's been neat testing and adapting successfully.

That's more what we do at Unique Diesel, custom projects, not really store product items.

Thanks for those that have followed!
 
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