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Topic: Power Tech Fan Belt Replacement (Read 449 times) previous topic - next topic

Power Tech Fan Belt Replacement

I have a Power Tech 12K generator, model # PT12KSIRR in my 2000 U320. 
Buzzing / rattling noise in front of coach when generator running.  I believe the noise is a loose fan belt.  The belt has a little over 1" slack.  I'm thinking this may be excessive and the noise is only when under load, as when the air conditioner compressor is running.  When AC is turned off, the noise goes away.  May be something else but want to start with what I know to be wrong.
I want to replace the belt but cannot find a procedure for its replacement in any of the documentation I have or online.  I can most likely figure it out, however, past experience has taught me I sometimes take the long route.  So if anyone has done this, could you share how you did it.  Do I have to slide the generator out?  It looks like if i take the front cover that surrounds the engine access cover, I might be able to reach in to remove the belt and adjust new one.  Any help is appreciated.  We will be in the Magnolia Branch Wildlife Reserve, Atmore, AL this week.  Will pick up a new belt today and hopefully get replaced before we leave on Friday. 
Bill and Joyce, The House2 and Dashboard Pig III
2000 U320 4210 CAI (The House2)
Build # 5733
2019 F150 King Ranch FX4

Re: Power Tech Fan Belt Replacement

Reply #1
I doubt the the fan belt is causing the noise. Things I would check if it is the rear bearing or maybe
motor mounts also once when shutting of the gen engine there would be a rattling sound and it
turned out to be loose bolts that held the gen slide from moving. 
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Power Tech Fan Belt Replacement

Reply #2
I'm also a victim of loose gen slide bolts.  Thought I had a major problem. The generator tech was also puzzled for a few minutes. Solved with addition of a rubber washer.
1998 36 foot U270 Build No. 5328 WTFE, 900 watts solar, Victron controller, B2B, bat monitor, 600 AMPH lithium with 2018 Chevy Colorado toad, SKP #110239, Motorcade #17781, 2021 Escape 17B for when Coach is broken down and campsites are too small, retired and full-timer since Dec. 2020. Part of RV family since 1963.

Re: Power Tech Fan Belt Replacement

Reply #3
I, too, wondered how to remove that belt as it doesn't have a tensioner.
Take the 4 bolts that hold the top pulley off. Comes right off and goes right back.

Re: Power Tech Fan Belt Replacement

Reply #4
Thanks for the replies.  The more brains on any given problem, the better.  This morning I took a closer look at the belt with help of a small extension mirror.  Belt looks good, no cracks or damage that I could see.  However, I fired up the generator and noticed the buzzing noise went away once the motor smoothed out.  I can push on the front of the generator and the noise returns.  I repeated this several times with same results so thinking something is very close to the generator cabinet and when loaded, it vibrates more and makes contact with something it shouldn't.  I will crawl under tomorrow and see if I can find the culprit.  I also noticed the rubber shock mounts on the front were cracking as old rubber does.  Due to age, they may have squashed down a little allowing the problem.  Will post what I find to be the cause, when I find it. 
Bill and Joyce, The House2 and Dashboard Pig III
2000 U320 4210 CAI (The House2)
Build # 5733
2019 F150 King Ranch FX4

Re: Power Tech Fan Belt Replacement

Reply #5
My generator is in a quiet box and I have noticed that under some load conditions, the door to the quiet box rattles.  I've shoved some 1/8" silicone rubber strips between the side of the opening and the door and that seems to help for a while, then it needs to be moved/adjusted.
Keith
2003 U320 38' #6197

Re: Power Tech Fan Belt Replacement

Reply #6
To finish this topic.  The buzzing sound from my generator appears to be an exterior panel vibrating against something.  By pushing on the top right (facing generator) corner of the generator, I can make the buzzing stop and start.  I noticed the rubber shock mounts are cracked so maybe they have settled some, allowing the cabinet to make minor contact with the exterior box.  If that makes sense.  My rocking of the generator seems to have fixed the buzz for now I think replacing the shock mounts would be a good place to start.  Thanks for all your replies.
Bill and Joyce, The House2 and Dashboard Pig III
2000 U320 4210 CAI (The House2)
Build # 5733
2019 F150 King Ranch FX4