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aggies09
05-10-2022, 09:48 PM
08 Marathon. RTU screams on startup. I pulled cover and when I spin the fan it growls bad. Feels like a bad bearing. Has anyone replaced this? If so, what did you do? Advice appreciated.
BadFitter
05-11-2022, 01:56 PM
Is it an 2008 original?
Gil_J
05-15-2022, 08:54 AM
Tony,

The outside fan motor should be readily available. Get the rubber mounts too while the motor is out. Make sure the fan is still good. It's pretty common for them to eventually get loose at the shaft.
aggies09
05-29-2022, 10:16 PM
Repairs complete. This was a Royal PIA. The motors needed to be replaced. The motors are obsolete. At Marathon’s direction I found some for sale on eBay. After swapping motors out I found that the shaft of the motor did not come threaded so there was no way to fasten the exhaust fan to the shaft. I dug around and found an old tap that I could use to thread the shaft. That was successful. I swapped out the capacitors while I was in there. So for $340 in parts and a significant amount of frustration, my wife and our traveling zoo are once again cool and comfortable. Oh, and it is much quieter now. If you think you may need this repair in the future you should probably acquire a motor or two.

Safe travels all!
Pete
05-30-2022, 09:36 AM
Way to go Tony!!
Gil_J
05-30-2022, 09:29 PM
Tony, nice job! I'm surprised those motors are already obsolete.
aggies09
05-30-2022, 11:10 PM
Tony, nice job! I'm surprised those motors are already obsolete.

Planned obsolescence I’m sure. Marathon still uses the Coleman Maach 8 on its new coaches, but it is a newer design with different parts.
MIsheeTX
08-21-2022, 06:34 PM
Hi Tony,

Are the Coleman Mach 8's easy to obtain? I know of someone that can install them, but am looking to replace all 4 of them on my 2004 Marathon H3 D/S. The original units are still working, but during this past summer of extreme southern heat (June/July 2022) from TX to Alabama, they were really put to their test and began to fail (2 of 4) and not cool well. Decided to replace them. Will the new Mach 8's work in place of the 2004 units (that are not as low profile as the newer ones)? Thanks for the help, Mike
aggies09
09-02-2022, 09:58 AM
Sorry for the delayed response. I think the Mach 8's are all readily available. They pretty much just bolt on, there is nothing sexy to the replacement. Actually probably easier than repairing one.