How Does a Viscous Fan Clutch Works in Your Workhorse Chassis With a 8.1 Vortec Engine W8002567

Why do viscous fans clutches fail? lets take one apart and find out.
This clutch came of a W24 Workhorse with a 8.1 Vortec engine with over 70,000 miles
If you need a new clutch see this video • WorkHorse Chassis 8.1 ...
Preferred clutch to use OEM W8002567 W0007657 W0000193
www.ultrarvpro...
Optional 8.1 Vortec Fan Clutch if you cant get OEM
GM Genuine Parts 15712914 15-4712 Engine Cooling Fan Clutch amzn.to/3B0hcyu
Note the 4 Bolts I used in order to mount the alternate fan clutch where M10-1.50 x 16mm
My older detailed video on how to remove and replace fan clutch • 8.1 Vortec Fan clutch ...

[@jerryhoxsey6467]

I have over the years heard all kinds of theories as to how these things worked. NOW WE KNOW!! Thanks Kevin

[@barzalou]

Lets make this official... Yes, I did enjoy the video. Now as you were saying, around 70 to 80 000 miles, it's normal for it to fail. But, you've gotta figure also where did this W22 live most of it's life. If it was down south, in torrid heat, contrary to us, up north (Canada), these conditions are also a big factor. Thanks for the schooling 😉🙂

[@ktoutdoor]

Interesting I did not think of that. But I try to avoid the cold...lol

[@RickBaconsAdventures]

Silicone oil is used because it stays thicker at high temperatures. In a pinch once, I drilled and tapped a hole in one of these and mixed up some silicone brake fluid with molykote 111 silicone grease until it was the right viscosity, then squirted it in the hole with a syringe. Worked like a champ. They typically leak all the fluid out around the control shaft under the spring. If you look, the springs are always oily and covered with dust on "worn out" fan clutches. Seemed like there was a little evidence on this one.

[@ktoutdoor]

Rick do you still have the ticking sound on your Allison?

[@RickBaconsAdventures]

@@ktoutdoor Yes, we've put about 10,000 miles on it with the ticking. Towing our trailer for camping and hauling tractors. it's still working fine even with the ticking. Everyone is stumped

[@ktoutdoor]

@@RickBaconsAdventures When you find out what it is please let me know.

[@RickBaconsAdventures]

@@ktoutdoor Will do! You have a lot of great videos so I am often around your page. I have a really long writeup about the noise and work I've done in the description of the video if you didn't already see it. I've got pretty good equipment and credentials so I'll be doing all the work myself if and when it decides to become a problem!

[@oemytech]

Great dissection and I think you have discovered why they cost so much.

[@214DTownDallas]

You just saved me a pain in the @$$ with your explanations! Amazing mechanisms

[@glocksm40]

Very interesting Kevin! Thx for sharing !! Scott

[@axtell1966]

Best explanation I have seen by far.

[@ktoutdoor]

Thank you very much 😊

[@CJ71234]

Wow, thanks Kevin, I also wondered how the fan clutch works, very informative, thanks for taking the time. I also noticed the roar of the fan when the engine is still cold and wondered about that, I believe you are correct that the oil drains out.

[@ktoutdoor]

Yes that has been bugging me for a long time ..lol

[@JavierMorales-pz9jd]

Hey!! Greetings from Colombia South America!! Nice video !!

[@ktoutdoor]

Thanks for watching have a blessed day.

[@AlphaZuluPhotography]

A lot of times it’s not even a bad fan clutch. It’s a bad radiator with an internal blockage. It doesn’t allow the hot air to flow over the fan clutch to engage it.

[@ktoutdoor]

I concur, I address that problem in this video kzbin.info/www/bejne/j2mVeJ2tl7l9pK8si=pimoTwfDpPG_DXFK

[@commentsedited]

Drill a hole and thread it pipe and fill and plug. Done mine.

[@tomkelly3896]

Ok...i nust cut the coil spring with a dremmel tool....and was able to turn the valve to let the fluid flow....its workin...but i assume the fan will stay mostly engaged now ....thats ok cause im in s. Az...temps are 100 to 110.....i will turn valve closed in oct ....and see if it operates as normal when air temps drop✌✌✌ good luck

[@ktoutdoor]

Cool let me know how it performs

[@warryckscown5620]

My 1990 LJ78 400k, auto , has a viscous fan.. I changed the radiator and thermostat bout 10 years ago , when I tow my trailer with the 1200kg buggy over the hill on way to coast the temp would rise slightly , but the temp light for tranz would light up, I just pull it down a gear, run the revs at bout 3500, after bout five minutes it would go out.. I can hear the fan working.. holding that ratio going down the other side, I hear the fan noise fad away.. The radiator caps these day are junk.. The stem the attaches the spring and seals etc come lose on the top, allowing air to be drawn into the radiator as the engine cools . Radiator should be full to the seal when you check it before first starting it..

[@ktoutdoor]

Thank you for contributing

[@doronkra4304]

very good:-) thanks

[@josezambrana5773]

I changed my fan clutch of my fj cruiser for a new one. I see that when cold the blades move not so freely and when hot it gets much harder. I have seen that the engine makes more effort and has lost acceleration. Could it be that the hardness of rotation of the blades influences the motor to slow down?

[@ktoutdoor]

Thank you for contributing.

[@rss608]

S0, where can we drill a port to fill it?

[@ktoutdoor]

I don't think it would be worth the effort.

[@johnnisley9715]

Very interesting, thanks for sharing!

[@lsolo437]

I have always wondered why the fan clutch is engaged for a bit of time during a cold start. Now I know, thanks, Kevin

[@ktoutdoor]

Yes it was always a mystery to me also. We be getting smarter every day ..lol

[@FilthTrackz]

Fantastic video.

[@commentsedited]

Wife or girlfriend take away the grinder?

[@frankharding5643]

I used to work at Borg Warner and made fan clutches back in 2002.

[@ktoutdoor]

Can you tell if this was made by Borg Warner?

[@tomkelly3896]

This morn i cut the coil spring with a dremel....and then was able to turn the valve to open position.....fan is now engaged...temp is down 20 degrees🤠🤓😎🤗✌✌✌✌

[@ktoutdoor]

How cool is that!! Great idea

[@davidebarra5691]

It's a centrifuge in constant motion. It seems that by design it will eventually break down the oil components and cause them to leak out. Good forensics!

[@tsdd.1567]

What happens if I bore it and lock the fan permanently to the axe? Would this solution destroy the belt?

[@ktoutdoor]

No the belt would be fine but it would but it would hurt your fuel economy a lot. But I done that very same thing with my old 1995 Nissan pickup truck.

[@tsdd.1567]

@@ktoutdoor Thanks for the reply. I agree.

[@shilosheena]

Good info I subbed have a 05 endurA super c with the 8.1

[@ktoutdoor]

You got a great engine there

[@tomkelly3896]

Did the spring just pop up off the valve easily...or did you cut thru a tac weld of some sort? Thx im considering popping mine off and leaving the valve open in az summer heat...tacoma running at 220 degrees...non towing😲🙈😲🙈😲

[@ktoutdoor]

Seams like it was held in place with epoxy. But with its age I'm sure your past do for a new fan clutch

[@tomkelly3896]

@@ktoutdoor i just did a cardboard in front of rad test....ran motor up to 224....did a laser temp test at the clutch...it showed 205 to 208 and didnt engage.....so i see a self tapping screw comin its ,way very soon😁🤣😂 it does engage when i first start it up ...for about 15 seconds.....then its done......2014 tacoma 4.0

[@tomkelly3896]

@@ktoutdoor very hard to get access while its still on vehicle.....i was going to try to pop off the spring and just turn the valve open....cant find anyone who has done it

[@ktoutdoor]

I would be surprised if it made a difference. But let me know if it does.

[@tomkelly3896]

@@ktoutdoor will do....i.may not mess with it for a week or 2.....im headin to grand canyon ...n rim

[@lindanadaud9698]

Great video. Thanks for the info.

[@ktoutdoor]

Thanks for watching

[@nicholastinling1022]

Thanks Kevin. As always a very informative video. It would be interesting to see what differences there are between OEM and aftermarket products.

[@ktoutdoor]

Thanks for watching

[@andrewhelmer7710]

very useful demonstration thank you

[@ktoutdoor]

Thank you for watching, have a blessed day.

[@danfarris135]

I still have the scars on my left arm from a viscous fan attack in 1992. Bit me real good when I leaned in to work on the carb while it was running. 😁

[@ktoutdoor]

Those things can be deadly