Whose Fan clutch (aftermarket) kicks on earliest?

[midniteplowboyy]

AM General, W.W.W Willliams, and Hummer, but I'll bet its expensive.

Try some of them guys on ebay selling the 6.2 HMMWV pull out engines. I'd bet they would take one off and sell it.

Check with ShawnR on here, he had one he took off his 6.2 HMMWV engine.

 

[Matt Bachand]

Matt, that HMMWV fan clutch would work great for you. I may put one on my 93. They are hydraulic, take about 100psi to release, there either fully engaged(no pressure) or fully disengaged(pressure), with no in between like an air fan clutch on a semi.

They basically have a pressure relief valve(set at 125psi) in the return line from the steering box, the bypass oil from the relief valve is returned to the reservoir like normal. The fan is "T"d into the 125psi line, to the fan clutch. To make the fan disengage you need a solenoid "T"d into the 125psi line, before the pressure relief valve to dump pressure, it bypasses oil around the relief valve.

The solenoid/relief valve is all one piece with three ports on the HMMWV, the solenoid valve is normally open(redundancy, so if it looses voltage/fails, it dumps pressure and the fan comes on). One problem, the HMMWV is 24v, and I think the civilian H1 were also.

But you can build it, its simpler than I can explain it. Basically you need a normally open(flowing) hydraulic solenoid valve, pressure relief valve, three "T"s and some hose/clamps.

Then just a temp switch of your choice screwed into the engine(and a manual override switch inside of course,lol)

That is actually ideal. My clutch only engages when I'm loaded up with plow. The rest of the year I only hear it when the engine is flooded with heatsoak enough to make it engage, a few seconds of driving and its off.

Meaning. the ONLY time my 6.5 EVER needs the fan, is when I have the plow on. THe rest of the year it runs perfect without.

 

[Missy Good Wench]

OK bhere is the real deal.

Some time ago I pondered this same debacle. The viscous drive clutches from any Mfg are in my opinion, less than optimum. They work off airflow through the radiator (as you already know) to make the bimetal spring on the clutch activate the valve and engage the clutch..

Now as was mentioned at time you almost have to stop for the clutch to really take ahold. Poor system at best.

A full mechanical clutch would be far better, AHHHH HAAAA.

Now the T444E navistar in the IH trucks uses (on some models) a Hortor electric clutch.

This is the Powerstroke V8 incidentally.

The clutch screws onto the hub similarly to the late GM 6.5's but with a different thread size.

I bought one of these clutches. ($500) and then devised a way to get it onto the GM Pump.
The shaft size on the GM pump is the same as the 444E (stroke)

The secret is that the flange from the GM pump must be replaced with one from the stroke and then its off to the rodeo.

The Horton setup uses water temp to operate the clutch via a temp switch rather than air temp.

Simple and easy to set up but not cheep $$$$$$$$$$

New Pump
Flange from old stroke pump
Horton fan clutch (will accept 95 GM 6.5 metal fan)
Get flanges pressed on and off (pump rebuilders can do this easily)


For special applications this is sweet.

I made one up and have it sitting on the shelf. The only reason its not on the rig now is that I have yet to work out the final details of keeping the AC system working when the fan is off.

Need a port into the AC high side to activate the fan when pressure exceeds 250PSI

Also really need some air constantly for the AC condenser to work right.

For non AC truck it's easy.

Here is a link to the Horton catalogue

http://www.hortonww.com/catalog/index.asp

The unit you need is a 996124

Go to the catalogue and type this part number in the search box.

Also you will need to get another pump pulley and modify it in the lathe to fit the new hub pilot and also so it will bolt on.

Simple job though.

Here are some pix of my unit.

Hope this helps

MGW

 

[Matt Bachand]

MGW to me this sounds completely perfect system for our rigs. Have the switch set on to engage the clutch when CTS is reading 200 for example. Then you never have an issue with clutch/fan engaging, once the truck is beginning its 'upward climb'.

My issue is different than the 'towers' issuses, as my big dumb plow does all sorts of stupid things to airflow, even possibly making it go backwards at certain speeds. I have emailed JK about his clutch, and he brought that to my attention. I agree. I have tried lowering plow a few inches leaving it 2" above ground, but for road travel, that is just plain scary. Hit a bump with a raised mainhole cover and BAM, scare the shit out of you at the least. Break something at worst. I've tried making air damn to put on to stick out above plow and 'scoop' the air into the radiator to help engage the clutch. Looks stupid, and never worked right.

My plow is 9' long, meaning I have to leave it angled to abide by laws of being no wider than 8' 6", and to not scare oncoming traffic and threading needles of other trucks w/9' plows.

When its snowing, you can see the plow's air resistance blowing the snowflakes all over the place, BUT towards the radiator of the truck, meaning airflow is doing the same.

A positive locking clutch switched on at a said temperature whether that reading is from a 2nd CTS type switch threaded into the PS head, or another spot would be ideal for everyone.

Why not have that fan engage at 200, and disengage at 195? Or engage at 205 and disengage at 200. Or something other than dependant of airflow.

I would imaging that 'drafting' on the highway may disturb airflow enough to not heat the clutch up also. But it takes big balls to draft as close as the big rigs do.

Sometimes on the highways they get up right behind md and help push me along, its scary! I must be an easy draft target, i'm big enough to screw up airflow making it good for them, yet small enough that they can easiliy see over me. When I picked up my tires I got in a truck train for a few minutes, but I didn't have balls of steel to trust the trucks in front of me for long, so I bugged outta it.

 

[Matt Bachand]

Kennedy's Email had distict disclosures saying its confidential and not to post/print for public display, So i cut/pasted it, but then deleted it after re-reading the disclosures.

 

[Missy Good Wench]

Yess I agree.

This is not a quick fix but will give you the control you need. The KIT comes with all the wiring and goodies to hook it up.
A dash switch to manually turn the fan on and leave it on too.

Now I know if Li'll O'l me can do it most of you strapping young lads can handle it easily.

Getting the flanges swapped out is not hard. I had a local water pump builder do it for me. It can be done in a press if you do it right. The trick is to hold the flange correctly while pushing the shaft out and then supporting the shaft on the impeller side while pressing the new flange on.

I got my stroke flange from a Diesel shops scrap bin off a worn out pump.

Ya'll have fun with this one.

I will help with more info if I can.

MGW

 

[Missy Good Wench]

Drafting with a big rig is not a case of BIG cahonas but more like NO brains

MGW

 

[Missy Good Wench]

Another Plus with the horton setup is that the rotating mass is far less than with the viscous clutch.

The electric clutch is stationary and is held with a fabric strap from turning.

The mass is reduced by half me thinks.

That fan will really howl too as it will be running full shaft speed and not just 80% at best.

MGW

 

[Matt Bachand]

Yep, manual switch would be perfect actually. These trucks working hard are not made for 'some guy' or 'the wife' (no offense MGW) to drive it blindly and not watch gauges.

 

[Acesneights1]

Missy,
what about using the pressure switch of a Peterbilt. IIRC it is a low cut off as well as extra terminals for fan operation. The Pete's had the air engage version of the Horton but it was still electrically controlled. IIRC some R Models used the same switch as well as KW's. I think it was on the low side but it controlled the fan somehow. The only thing you would have to be careful about is on our trucks there is no "thermostat" to control compressor operation cycling. it cycles by high pressure which is the switch on the dryer. Screwing with that could cause the system not to cycle properly and blow apart. You are very close to making it work though. I really really like what you did. It's funny you posted that because All I could think of is how nice it would be to have something like was used on the 425 cats etcs that was direct engage temp sensor clucth. As always very good work. as for the a/c thing I think you could screw the Peterbilt sensor right onto the filling where you chagre the system/ hook gauges if it was a retro fitted R12 system They have the same thread as the gauges hose. Otherwise it would be easy to fab I'm sure.

 

[Acesneights1]

BTW, I made this argument on the old site as some might remember. It was my first post over there. The engine fan is only needed below 20MPH. I proved this theory with a Western Star. It had 3406B 425 Cat. I was in NYC hot summer day grossed out at about 120K lbs. The Horton clutch puke. I let the truck cool off and carefully nursed it back to the highway with many stops. Once I got on the LIE eastboud I went 60 mile at between 55-70 MPH and the truck never broke a sweat. I have long argued that even though the fan's kicking on at highway speed may help the symptom, it's not curing the problem. The problem is the cooling system is not getting rid of the heat becuase it is either undersized or restrcited. As many of you are familiar with my annnual overheating towing the camer issue, I will be doing a little experiment in the next few weeks when it gets good an hot and time allows. I'm gonna remove the A/C condensor and take the camper for a nice long tow up a real steep grade and see what happens. Maybe I'll prove myself wrong but I gotta try it.

 

[Matt Bachand]

I have no AC so keep the ideas rollin. I'm just afraid doing this is beyond my ability to work on the truck over the weekend, and still be able to make money with it come monday.

 

[Missy Good Wench]

My Western Star uses a trinary switch to control the Low side cut off on then AC (Low charge) too high a pressure will tun on the fan clutch to cool off the AC system and also if extreme pressure is reaed in the AC it will shut it off.

The fan is normally controled by a Thermal switch in the water jacket that runs the fan when temps reach 195F.

Matt

No offense taken

Most neophites need to drive something that will fend for itself. (Computer controled and basically idiot proof)

I have many folks from time to time that drive my dually so I need to devise a system that will protect things from frying.

Another issue is this, years ago the GM fan clutches came on fairly early. My 454 trucks would start the fan howling at around 210F (Gauge) and suck in all the bugs for miles around.

Too many people piss and whine about the noise so the manuf's set the engagement temps way up in order to end the complaints.

Wrong move in my book.

My old 86 454 dahooley would never overheat and the 9 blade fan would howl like hell as soon as the temps came up at all.

MGW

 

[Brooklyn Tow]

You running a Kennedy then? How do you get it to disengage? Like I was saying, I woudn't mind having to swap my Delco back on every spring. I don't want it to stay on for a 12 hour plowing duration though, when I only need it to drive too and from my plow routes, and to pickup and unload my plow.

Actually Matt, pulling over to let the clutch disengage, "Doesn't work"....Seems the only way to get it to disengage is to speed up RPM's and then she'll finally unlock only to lock up again in 10 minutes....To sensitive IMO.

By the way, if your against giving SSD your money, then you can just go buy a Severe Duty clutch from Hayden or any other Co. that makes them....As SSD and everyone else does......Even Kennedy's is rebaged, He just ordered them to his specs, that's why they engage early before anyone elses. (and there almost twice the price)

JMHO

 

[Matt Bachand]

Actually Matt, pulling over to let the clutch disengage, "Doesn't work"....Seems the only way to get it to disengage is to speed up RPM's and then she'll finally unlock only to lock up again in 10 minutes....To sensitive IMO.

By the way, if your against giving SSD your money, then you can just go buy a Severe Duty clutch from Hayden or any other Co. that makes them....As SSD and everyone else does......Even Kennedy's is rebaged, He just ordered them to his specs, that's why they engage early before anyone elses. (and there almost twice the price)

JMHO

Walt already lied cheated and stole more than enough of my money, I wont give him another penny even if it is for the exact product I want for the price he wants.

Oh your Kennedy fan, when your driving unloaded, how often does it kick on?

Is it the same in the Winter time?

I'd rather overkill for the winter months, hell even if it stays on way too much to be fuel effective its better than running the engine hot.

I do not however want it to stay on for the full 10-12 hours of plowing. That would be annoying and kill my fuel economy for sure.

I could just take your recommendations and try the heath unit.

I really wish someone would mainstream a lockable type system. Fabrication is not my cup of tea, given I need my truck the following monday.

A-Team Clutch perhaps is in the works?!?!

 

[Brooklyn Tow]

Winter temps are no problem....Only Spring and summer months.....Also, I thought maybe the clutch I got was defective, but TD stated the same thing I was experiencing.

I believe TD went with a Heath clutch, but you would have to ask him.

 

[Matt Bachand]

Winter temps are no problem....Only Spring and summer months.....Also, I thought maybe the clutch I got was defective, but TD stated the same thing I was experiencing.

I believe TD went with a Heath clutch, but you would have to ask him.

He did, for the exact same reasons you mentioned.

What T-Stats you run btw?

 

[Brooklyn Tow]

180* Robert Shaw

 

[Matt Bachand]

If your's is a 4-bolt maybe we can work something out if you want a heath, and I want the Kennedy.... I'll be ready to buy end of summer/fall time.

 

[Brooklyn Tow]

Let me know