I'm just starting a search for the answer, but if anyone knows the answer for sure, post it up please. I've also got this in the V-10 forum, but they seem to be slow today, with no responses....

My brother's 1999 F-250 V-10 has just developed a squealing A/C clutch pulley bearing. He's 90 miles from home and I may just go tow him in, but thought if there's a way to bypass the compressor pulley with just a shorter belt and maintain tension, I would take him the belt instead.

Dunno anything about V-10's, so I thought I'd ask y'all here.

Will a shorter belt work in this case? Is the routing the same with and without the compressor? If so, what length?

Thanks in advance!

Pop <!-- / message --> <!-- BEGIN TEMPLATE: ad_showthread_firstpost_sig --> <!-- END TEMPLATE: ad_showthread_firstpost_sig --> <!-- sig -->

 

I would just kill the power to the pulley clutch at the front of the A/C compressor, so it can't engage.

 

It's not the compressor's inner shaft bearing, it's the clutch/pulley bearing.

The belt has to go around the compressor clutch whether the compressor is engaged or not. That's the bearing that has gone south on him, and is squealing.

That was the purpose of my question, how to get rid of the belt turning the pulley.

He's made it back home, so this is going to wait until tomorrow when I can take a look at it.

All I'd like to find now in a forum search is the clutch bearing number, but it's not to be, so I'll have to pull it to find out.

G'nite all.

Pop

 

Didn't have to do this to MY truck, but to my brother's '99 F-250 V-10.

He got out to the track on Sunday for a race and he got a squeal under the hood and a "rumble". Turned out to be a bearing in the A/C compressor clutch assembly.

Got the new parts and fixed the clutch today. It's not bad, but I would suggest that on a gasoline engine that you remove the shroud and radiator, as it frees up a lot of room to work and isn't that time-consuming to pull them.

Here's what was causing the bearing to rumble and occasionally squeal:



I'd guess that the lubricant had eventually run dry, the rollers began getting hot, which melted the plastic bearing spacers, allowing all the ***** to run to one side, causing a LOT of play in the bearing with rumble and squeal. The apparent rusty lubricant seen is some PB Blaster I shot in there to assist the ease of removal.

Additionally, all three rubber "inserts" in the clutch plate were missing, allowing the plate to make contact with the other half of the assembly and rattle around, probably producing some heat.

The new part does not have the rubber dampeners, is a slightly different (conventional) design, and is likely applicable to '99 only, as my 2000 does not have them,



All-in-all, the double-roller bearing design is pretty forgiving, as it allowed the truck to be driven at least 150 miles from first noticing the squeal and rumble before getting it fixed without self-destructing catastrophically.

The cost for the new clutch assembly, including a new coil (which we did not use) was about $130. I set the air gap at just over .010", which is a little tight, but recommended by the local A/C repair shop owner from whom we got the clutch.

For those interested, the bearing is "staked" into place in the clutch housing, but it CAN be removed and separately changed (we didn't), and the old bearing number is an NSK 30BD40DF2. Googling that number, I found it's also a 5106-WCC from either Timkin or BCA/National. NAPA may have them on the shelf.



It can be had for as little as about $25.

It might make a nice weekend P/M project if you've got over 150,000 miles or so, and it's something I'll do before the next cross-country.

And, you can re-shim the clutch air gap at the same time!

So what's this "air gap"?

Turn your A/C to "off". Start the engine and go look at the clutch.

Notice that most of it is turning? Look at the "front" of it, the face closest to the degas bottle. Notice it ISN'T turning?

Turn on the A/C and look again.

The space between what WASN'T turning and what IS turning now is called the air gap. It's only thousandths of an inch, but it has to be there to cycle the compressor off, and it can't be too great because there's an electro-magnet that pulls it in to engage it. When the air gap gets too great, the magnet won't dependably pull it into engagement.

The spec is .014 - .032", but you CAN set them as low as .010". See:
https://www.ford-trucks.com/forums/5...ml#post4464164

Pop

 

One more thing to Pops post. The race was 6 hr endurance motorcycle race at Glen Helen, not a truck race.
Truck has in the past, a rattle which sounded like piston slab and pre-ignition. Had the motor into Ford for a new short block some years ago under warrenty. The noise has all but disappeared. The noise may be the rattle from the lack of the rubber inserts. Something to look at.
Lil Bro

 

"Lil" my a$$! He's bigger than I am!

(But the M/C racing keeps him in better shape....)

Pop