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JCarrollJr
10-03-2020, 09:27 PM
I had a problem with my engine cooling fan clutch not going into the high mode and had it replaced at the Prevost Car facility in Wintergarden, Florida on the way to Naples last year and as of right now it has between 1500 and 2000 miles on it and not quite a year since the installation.
I just today got the recall letter on the cooling fan clutches sold by Prevost Car during that time period and mine is one of the part numbers listed. I can't see the serial number to positively identify it. While looking for the serial number I moved the fan blades and found the clutch to be to be obviously dragging. The blades can be moved but the fan does not spin free. I would advise anyone that may be affected to check it closely.

Joe Camper
10-03-2020, 09:52 PM
Hey John I was shown the same letter yesterday. Let me add.

Not all of the prevo numbers get recalled only specific hubs between certain manufacturers serial numbers and those numbers r marked on a face thats sandwiched to the bracket. The only way to read the manufacturers number is to remove it. Short of that all u can do is loosen the belt and spin um.

JCarrollJr
10-03-2020, 11:25 PM
Yep, and I'm sure you remember that you detected that this one may have a problem. I'm wondering if Prevost in Wintergarden may have the S/N in their records. I doubt it, but possible. Just FYI, I drove it to Chattanooga to the radio shop and back yesterday and I thought it drove good before, and it did, you did the job on it but it now is absolutely unbelievable. Obviously like a zero miles new one. Also, it's been sitting since you finished it and the suspension hasn't leaked down any at all. Not one PSI. Job well done!! Headed to Naples 11/1. When are you heading to the Keys?

Fratto
10-06-2020, 01:51 PM
It is so incredibly disappointing that Prevost cant seem to figure this out. As you recall, I have had multiple clutches installed in less than two years. Some of them were bad out of the box, some failed at Prevost during the test drive and some failed after a few miles. I thought that I finally got a good one...no issues for 2000 miles. BUT darn if it did not start making noise when I left Kerrville a couple of days ago. A pre-trip spin came up with a slight rubbing noise. By the time I got it home, the clutch was binding enough that it can no longer "idle" when first started cold.

I will be calling Prevost Fort Worth later this week ... I am sure they will be over joyed to see me again.

twslp
10-14-2020, 01:54 PM
HI joe i have a question. their was a picture showing the small spring at the belt idler to support the idler if the mini bag fails. i read this and this morning ckd and mine was missing. is it something i need from prevo. or something i can get at the hardware. thanks terry.

Joe Camper
10-14-2020, 04:53 PM
Possibly both Terry but I'm sure it's available from Prevo. There is a machine screw holing it in be sure its not gouging out the ac compressor case like the one I was looking at. If it is find another way to fasten it so it doesn't do that. I used zip ties on Pierre's I should ask him to go take a peek and see how that's doing. Its not good when u start crashing your test pilots u know.

twslp
10-14-2020, 05:40 PM
Thank you for the quick info. i do not see a screw. im sure it was there when i changed the belt. I found a spring. one longer @ ace hardware. im going to cut it down. do you know the tension it should have ? just touching or ? and i will tie it. thank you.

pierrem53
10-14-2020, 10:33 PM
Joe and all,

I looked about a week ago and it looked good. This post prompted me to go out and check again. Zip ties are holding up well. Where you repaired the abrasion with JB weld, It is starting to rub a bit and I see very minor abrasion. I will add this to my maintenance list which will be addressed in about 3 weeks.

Joe Camper
10-15-2020, 07:41 AM
No tension. Should be slightly gapped.

twslp
10-15-2020, 10:20 AM
thank you.

JCarrollJr
11-02-2020, 08:55 PM
<tbody>
And now for the rest of my cooling fan story story.
I called the Prevost Car facility and talked to Dave in Service about the letter, the new clutch being in that group and what I had found by attempting to spin the fan. We talked a couple of times about a solution and I told him that if he was agreeable that I would stop by Wintergarden on the way to Naples and let them take a look. He said to give him a little while to do some checking. He called me back a short time later and said to just sit tight here at home and that Jason Greenway, the Prevost Moble Service Tech out of Atlanta (100 miles South), would be here at 10:30am this (Monday) morning. At 10:30 sharp This morning Jason rolled in. After just a minute of looking he determined the clutch did have a problem and proceeded to change it. He finished up and was gone by about 2:00pm. He partially disassembled the old clutch and determined that an internal part had been installed backwards during assembly by the manufacturer.
And now for the bottom line. Would anyone like to hazard a guess as to what the cost was for this kind of first class service? The answer is not one red cent.
In the times we live in today, I think that this kind of customer service and attention to a problem that was not the fault of Prevost Car, but that of a vendor, is absolutely phenomenal! I just wish that they made sports cars and pick-up trucks. I can't help but wonder if there are other manufacturers of motor coaches out there of this caliber. I have my doubts.
My sincere thanks to Dave, Mike and Jason.
John


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Fratto
11-03-2020, 10:25 AM
Maybe I need to run Jason down somewhere ... I am still waiting for Fort Worth Prevost to call me back and let me know what the plan is for yet another clutch.

twslp
11-03-2020, 04:06 PM
HI JOE. prevost sent me two one for a spare i ordered. I had cut one down I found at ace hardware and installed before the prevost order came. we drove to vegas and back a quick trip. looks good. FYI mine has tension. no screw. held in place by tension maybe 20 lbs or more. i did zip tie it. and i will watch it. also the prevost replacement spring is almost twin to the one i cut down. thanks.

Joe Camper
11-03-2020, 08:44 PM
I'm glad I spun that fan for u when I was there John. Worked out good.

Gil_J
11-03-2020, 09:24 PM
John, your experience is a big reason to own a Prevost.

JCarrollJr
11-04-2020, 09:41 PM
Yep. First class all the way. From the product, to the support of it.

Fratto
02-08-2021, 11:06 AM
The good news is that we just pulled into West Palm Beach for the Prevost show! Lots of great looking buses here :-) Bad news is that 20 minutes north of here we ... you guessed it ... lost another fan clutch. This one has less than 2000 miles on it. Maybe some one hear at the show can help us get this figured out. I have honestly lost count but I think that this is the 6th failed clutch in 2 years.

Gil_J
02-08-2021, 04:14 PM
Mark, run down Prevost service. They are here. I'm surprised your version of clutch has been such a problem.

BadFitter
02-08-2021, 04:33 PM
I'm sure Mark was betting heavily on the Chiefs.

Mark could be a real asset... see what he bets on and go opposite.

Sorry Mark... hope your luck changes soon. Bad streaks come to an end.

georgew
02-08-2021, 09:30 PM
HI JOE. prevost sent me two one for a spare i ordered. I had cut one down I found at ace hardware and installed before the prevost order came. we drove to vegas and back a quick trip. looks good. FYI mine has tension. no screw. held in place by tension maybe 20 lbs or more. i did zip tie it. and i will watch it. also the prevost replacement spring is almost twin to the one i cut down. thanks.
Can someone post picture's and more info about the discussed problem
Thanks late to the discussion

Joe Camper
02-09-2021, 03:49 AM
That's a medium tension spring and bracket that keeps the idler pulley with tension if the belt tension bellows looses air on the cerpentine belt for the radiator fan.

georgew
02-09-2021, 04:55 PM
That's a medium tension spring and bracket that keeps the idler pulley with tension if the belt tension bellows looses air on the serpentine belt for the radiator fan.
If the one bellows loses air wouldn't the other also and then you wouldn't have rotation of the 90 degree gear box thus no rotation of fan. Am i missing something?

Fratto
02-21-2021, 05:22 PM
So Johnny and Kevin worked with me at the Prevost show. They confirmed that the clutch was bad and installed a new one while parked at the show. Cant say enough good things about the thoughtful and caring way that Johnny worked on the coach.

During the install we found an exhaust leak at the discharge flange of the turbo. Kevin found some parts and Johnny tried to put them in the next day. Unfortunately, the elbow would not quite mate up with the existing flange. Apparently there are three sections of piping between the turb aond muffler. It is possible that one of them is the wrong one and that led to the failure. Parts were not readily available so Kevin found some heavy duty flex and Johnny installed it as the show as well.

After the show we drove up to Winter Garden and spent 8 great nights there. Even though they were booked, they managed to squeeze us in over the days and we replaced coolant hosed, sight glass, coolant level sensor, flushed the full system and put in Joes Green stuff and ... fixed a leaking fitting on the transmission cooler hose.

Anthony, Dave, Johnny, Mike, Orlando, Eugene, Michelle and others were so great we really did not want to leave. But the weather broke in Texas so off we sent.

Love being part of the Prevost Family and looking forward to the show next year.

Joe Camper
02-21-2021, 06:33 PM
Glad to hear that Mark. I'm curious how many different choices of coolant does prevo offer???

georgew
02-21-2021, 10:34 PM
Still lost on this spring and where it is to keep tension. Would love a picture.
If the one bellows loses air wouldn't the other also and then you wouldn't have rotation of the 90 degree gear box thus no rotation of fan. Am i missing something?

Joe Camper
02-22-2021, 05:40 AM
It is attached to a bracket that is attached to the idler pulley that the cerpentine belt for the fan rides over the top of. In the event of a failure u can strap tight the other tripple belt driving off the crank in a number of different ways. Really no way to tension that fan belt like that.

Joe Camper
03-02-2021, 06:49 PM
17377

17378

Here is the backup spring and bracket for the cerpentine fan belt.

BGLogistics
03-02-2021, 07:05 PM
Is that spring just a certain year range thing, or was it OEM on all those type fan drives? If so, mine is MIA

Joe Camper
03-02-2021, 09:55 PM
Billy u know how prevo is. Look in the manual it should be there if it came on the chassis. Or call Elgin.

Here is the prevo part numbers.

Bracket 052477

Spring 502247

Gil_J
03-04-2021, 10:08 PM
Yep, a common failure item. I discovered broken ones on 3 buses I inspected in just that last few months. When broken, the fan can rest against the radiator shroud when the belt bags deflate.