Fan Problem

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Oldav8tor
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Fan Problem

Post by Oldav8tor » Mon Oct 14, 2019 1:41 pm

Today was a beautiful fall day in Michigan and with rain in the forecast for the next few days I decided to take my 1917 Touring for a spin. About seven miles from home I got a whiff of burning rubber and thought "Some farmer must be burning tires." The next moment there was smoke coming out of the hood louvers and around the pedals in the floorboard. I quickly pulled to the side of the road and shut it down and the smoke stopped.

Opening the hood I saw black droplets on various surfaces but they weren't oil or grease. Looking closely I determined they had come from the fan belt. Apparently the fan had either totally or partially frozen, and the slipping belt quickly overheated, melting the ridges on the belt.

I loosened the fan shaft nut and re-tightened, making sure that the fan would spin. When I started the engine, it turned OK and no more smoke. I drove home without incident.

Obviously I want to prevent this from happening again. Should I be modifying the hub with a Ball Bearing Fan Hub Cartridge such as this one from Langs <https://www.modeltford.com/item/3962BC.aspx>? Or is there something else I should do?
1917 Touring
1952 Willys M38a1 Jeep


Scott_Conger
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Re: Fan Problem

Post by Scott_Conger » Mon Oct 14, 2019 2:05 pm

1. is the fan a greased fan hub or an aluminum fan hub with oil plug?
2. has it been rebuilt?
Scott Conger

Full Flow Float Valves - deliver fuel like Henry intended!

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Oldav8tor
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Re: Fan Problem

Post by Oldav8tor » Mon Oct 14, 2019 2:10 pm

Greased - No, not rebuilt.
1917 Touring
1952 Willys M38a1 Jeep


Humblej
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Re: Fan Problem

Post by Humblej » Mon Oct 14, 2019 2:45 pm

Take it apart and inspect it, may need new bushings, may need bushings and shaft, may not need anything but cleaning up. When you put it back on keep the belt loose, loose enough that you can turn the fan with your hand.

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Oldav8tor
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Re: Fan Problem

Post by Oldav8tor » Mon Oct 14, 2019 3:47 pm

When I was restoring the car I did take it apart, inspect and grease it. It wasn't loose on the shaft and spun easily. You could turn it by hand with the belt installed so it wasn't too tight. I don't know what happened today but the fan definitely locked up briefly and smoked the belt.

I removed it today after my first post and looked it over and everything seems fine except for some rubber cooked on one side of the fan pulley.

I had to order a new belt so I bit the bullet and ordered a Ball Bearing Fan Hub Insert as well. I have a fall tour coming up shortly and need to come up with a fix pretty quickly.
1917 Touring
1952 Willys M38a1 Jeep


jab35
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Re: Fan Problem

Post by jab35 » Mon Oct 14, 2019 4:11 pm

Even tho it spins freely, do check the shaft as advised. I would not use new needle bearings on a worn shaft. best, jb


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Re: Fan Problem

Post by Scott_Conger » Mon Oct 14, 2019 6:04 pm

Tim

with modern driving, you want a new/perfect shaft surface. Loose belt to the point that the fan will spin when engine shut off (it does no work when driving, and simply pulls air when stopped at a light). The grease cup must be kept full, and a twist given to it each morning of a tour to the point that some grease comes out the front and back (wipe off with rag).

If you are not seeing grease exit both places, you do not have enough grease. Ball bearings may seem the more reliable fix, but ask yourself this: my bronze-bushed fan just seized and now spins fine...would a ball bearing that seizes operate just fine after lubing?

Truth be told, I run a ball bearing hub on my tour car...it replaces the later, oiled version of fan hub. That said, I carry a spare shaft and prepared bronze-bushed hub in the trunk to retrofit if necessary.

I just put a new brass hub with ball bearings on a 1910 Torpedo that I was running out of time on to fix the original fan. Customer was arriving from FL and wanted a RUNNING car. It was a beautiful thing (the hub) and operated very nicely, so I know that product works well, though had to do a bunch of custom shimming for it to have proper preload on bearings (very slight) and be spaced from the fan arm properly (it was not in line at all until that work was performed). Be aware that the cartridge might require similar fitting. Ball bearings don't like to be beaten with zero preload, and will fail quickly with too much preload. I have found that with regard to ball bearing fan hubs, some come with a spacer which preloads perfectly and others come with no distance piece and will either fret quickly with no preload or self destruct with too much. And finally, sealed bearings are not truely sealed, and permanent lubricants are not truely permanent. Ball bearing fan hubs will all eventually fail. It is best to be prepared for that to keep from future touring mishaps undoing your expensive trip. FWIW.
Scott Conger

Full Flow Float Valves - deliver fuel like Henry intended!


L.I. Tom
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Re: Fan Problem

Post by L.I. Tom » Tue Oct 15, 2019 1:12 pm

Tim
I had the same thing happen several years ago on my Roadster. It was due to lack of lubrication (my own fault) all I did then was clean it up put it all back together and keep fresh grease in it regularly. It's been fine ever since and that was probably three or four thousand miles ago it should be okay just keep it lubed.
Tom


Jim Sims
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Re: Fan Problem

Post by Jim Sims » Tue Oct 15, 2019 1:38 pm

The fans were ment to use oil and not grease. Grease will move away from the bearing surface and not flow back unless hot or under pressure but fluid oil flows back and continues to lubricate. Oil may leak and make a mess I use heavy oil like chain saw chain oil.


Jim Sims
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Re: Fan Problem

Post by Jim Sims » Tue Oct 15, 2019 1:42 pm

Correction to my last post. The early fans with grease cups do use a light grease.


YellowTRacer
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Re: Fan Problema #4

Post by YellowTRacer » Tue Oct 15, 2019 5:26 pm

You're running your fan belt way to tight. Scott hit the nail right on the head in his first paragraph. With the engine shut off I can reach in, put a finger on the fan blade and spin it and the blade will turn 3 or 4 inches. I just keep it tight enough to turn the pulley on the water pump (if it has one) and that's it. Moly EP grease, there's non better. Have never rebushed a fan, just keep it greased with good grease. Have never used oil in the aluminum type just grease. Works for me.

Ed aka #4

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Mark Gregush
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Re: Fan Problem

Post by Mark Gregush » Tue Oct 15, 2019 8:57 pm

I too tried grease on my stock fan hub (1921). Even set on the loose side, didn't take long for it to start making noise for lack of lube. Went back to heavy oil. Yes it makes a bit of mess, but the bushings get lubed.
I know the voices aren't real but damn they have some good ideas! :roll:

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1925 Cut down pickup

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Topic author
Oldav8tor
Posts: 366
Joined: Sun Jan 06, 2019 11:39 am
First Name: Tim
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Location: Thumb of Michigan
MTFCA Number: 50297
MTFCI Number: 24810

Re: Fan Problem

Post by Oldav8tor » Sat Oct 19, 2019 8:24 pm

I'm back on the road. The ball-bearing fan cartridge install went smoothly and the unit seems to operate well. The design is such that short of the bearings going bad I don't see how it could bind up.

Since I smoked my fan belt I've talked to others that have suffered similar problems, often without a good explanation. I'm just glad it didn't happen when I was on the Indiana Covered Bridge Tour where temps hit 90°. Hopefully the fan will be trouble-free for the foreseeable future.
1917 Touring
1952 Willys M38a1 Jeep

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