Big Radiator Fan "HUB"

[Jon Wehrenberg]

Jim,

Just to be sure, are you talking about noises from the clutch or the shaft assembly driving the clutch?

This is important because if the clutch (which free wheels at low engine temperatures) has bad bearings it can be locked to the driven shaft assembly and may not put the bus out of service.

If the driven shaft and its bearings fail that will disable the bus.

Also for those who may not be aware there are other bearings and idler pulleys across the face of the engine for other driven devices such as AC or the alternators which should be checked periodically. Those idlers can be serviced, usually by getting the bearing number off the part and pressing in a new bearing.

[Coloradobus]

JIM,

IS this growling noise they told you about audible from with inside the bus in the bedroom, or from standing outside?

[JIM CHALOUPKA]

Jim, it's not a noise per se, it is something that you feel in your fingers when turning the shaft by hand. No load. Belt off. Just spin the pulley by hand and then lightly feel the shaft as it turns.

JIM

[Kevin Erion]

Co. Jim, Yes, you will hear a growl if you stand near the Driver side Rad area. I am of the opinion that they will start to make noise and it will take some miles before they fail. What happens when they fail, I have no clue but might not be so good. Prevost Mira Lome had no less than 20 in stock. Why so many, maybe they fail a lot, just a guess!

[lonesome george]

Jim,
When first inspecting our coach one of the things I did was roll the cooling fan thru with the belt attached to get a feel for the thing, all was good.
After several short trips it started making a bit of noise so off it came. I'm thinkin just poke some new bearings in it, turns out to be lots more difficult than that. The bearings that were getting noisy are a double bearing arrangement, one inside the other, with the races built inside a flange. The part can be purchased from LINNIG Corporation. Tucker, GA 30084 ph 770-414-9499 for $250. but no stock and a 8 week delivery, so I requested air freight and the price was an additional $400. the clutch has two other garden variety bearings on the input shaft, add those in and the $1,100. new part starts to look better.
The replacement clutch has a different part number with some design changes, it looks like the bearings on the flange can be replaced without replacing the whole flange.
The maintenance manual says to wash the clutch with diesel fuel and rinse with water, DO NOT PRESSURE WASH THE CLUTCH. I DID and that could be what happened to the bearings and my $1,100 Lew bucks!
The new clutch makes no noise and has no vibrations that I can feel when rolling it thru by hand with or without the belt on.
Still Lonesome

[JIM CHALOUPKA]

Thanks for the info George.

Some guys pressure wash a lot. I have heard of fire alarms not liking the water either.

Were you implying that Linning Co makes the clutch assembly?

If they did not have stock, how did the next day air help you, or did I miss read your remark?

No matter how you look at it we got the shaft.
JIM

[lonesome george]

Jim,
Sometimes my crap is not to clear.
Linning Corp. makes the clutch and it is a nice piece of work and about the same price a air clutch for a truck but our's are two speed.
The 8 week delivery was for a standard ocean shipment from Germany for the part, the $400 additional fee was to have the part shipped by air to get it in a few days, I have no idea why the air charge is so high.
I gave up and ordered a new unit from Prevost.
I'm guessing that the part I needed is not stocked in the US because the unit has been redesigned.
I will never pressure wash the engine compartment again, Jon is spot on about using soap and a garden hose to wash the goop off.

[JIM CHALOUPKA]

My fan clutch assembly was delivered today and it is really a nice piece of work and that is something coming from a Machinist of 43 years.

Turning the shaft on the new one is like drawing a knife through soft butter.
The old is like drawing a knife through coarse sand.

I will take pictures and write up the job for those interested.

JIM

[Joe Cannarozzi]

The pictures I want to see are the ones where you rebuild the old one.
Get them by boat they will arrive in about the same time it takes you to get to the door

If the shipping expenses is not 400 how much are we talking about to do it with parts.

[lonesome george]

Joe,
The parts to repair my old clutch would be about $350.00 total if I wanted to wait for the boat. I don't know what the cost of parts would be to do a complete rebuild but some of the stuff in the clutch looks spendy.