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Topic: New Problem not making the wife very happy! (Read 706 times) previous topic - next topic

New Problem not making the wife very happy!

After all the help and problem solving yesterday with the generator faulting that was fixed.  Hit the road late and things started warming up, literally!

I do not have functioning dash air so I simply planned to run the generator and the roof top units. Did that from Florida in May and it was great. Until the back ac stopped working. Kind of.... it was making a ton of noise and not really pushing out any air.  When we landed for the night I got up top and opened it up and then ran the unit.  The fan motor is literally jumping around causing the fans to hit the sides. I tried tightening up the mounts but that did not help.

Any ideas? I would simply replace the fan motor but not sure where to find one especially on the road as we are right now.

As always, your help and thoughts are appreciated!!

kind regards from York, Nebraska (currently) headed to Lake McConaughy.
2000 U320 36'
Build #5705

Re: New Problem not making the wife very happy!

Reply #1 –
Could be mud dauber inside squirrel cage causing vibration.  If it now rubs on something,  I've even seen the squirrel cage broken.
https://youtu.be/7I9mNK7btVE
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: New Problem not making the wife very happy!

Reply #2 –
Grainger which is everywhere would have the parts. They are not the cheapest, most time, but seem to have these type of parts.

Is just the fan blade jumping round since the bearing on the motor bad or bracket for motor broken.  When you were up top was the unit cooling?

I agree with Jack above, check for something throwing the blade out of balance.



2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: New Problem not making the wife very happy!

Reply #3 –
Quote from: Jack Lewis –
Could be mud dauber inside squirrel cage causing vibration.  If it now rubs on something,  I've even seen the squirrel cage broken.
https://youtu.be/7I9mNK7btVE
That was what I was hoping for but both fans move freely with the motor off. The motor starts jumping around, literally.
2000 U320 36'
Build #5705

Re: New Problem not making the wife very happy!

Reply #4 –
Could be unbalanced by mud dubbers nest.

Could be a broken motor mount (really depends on brand and how motor is secured to the unit).
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: New Problem not making the wife very happy!

Reply #5 –
Quote from: turbojack –
Grainger which is everywhere would have the parts. They are not the cheapest, most time, but seem to have these type of parts.

Is just the fan blade jumping round since the bearing on the motor bad or bracket for motor broken.  When you were up top was the unit cooling?

I agree with Jack above, check for something throwing the blade out of balance.




I would have recorded it but it was dark, maybe I can do that later.  The brackets/ bushings are present. I am thinking something must have broke inside the motor but it is still turning. Crazy! No obstructions and no wiggle in the shafts or fans.
2000 U320 36'
Build #5705

Re: New Problem not making the wife very happy!

Reply #6 –
Quote from: wolfe10 –
Could be unbalanced by mud dubbers nest.

Could be a broken motor mount (really depends on brand and how motor is secured to the unit).
The mount is 4 attachments with bushings. They were not really tight so I tightened hoping that would be enough and it was not. Pulling the fan motor looks like a pain in the rear! With shafts coming out on both sides of the motor I did not think it would be very easy to find.

Might be time to upgrade!
2000 U320 36'
Build #5705

Re: New Problem not making the wife very happy!

Reply #7 –
I agree with the rest. Look for a mud dobber on the fan blade.  You would not feel it when turning the fan over by hand but when it got to speed it would jump all over.  Might be kind of hard to get to it or see it.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: New Problem not making the wife very happy!

Reply #8 –
Quote from: Farrarkc –
The mount is 4 attachments with bushings. They were not really tight so I tightened hoping that would be enough and it was not. Pulling the fan motor looks like a pain in the rear! With shafts coming out on both sides of the motor I did not think it would be very easy to find.

Might be time to upgrade!
Your air conditioner is 20 years old so no one would blame your for simply replacing it.
But, one side of that motor blows air over the refrigerant condenser, and the other side blows air over the refrigerant evaporator, sending cooler recirculated air inside your coach.  The second fan is called a squirrel cage design and it is quite possible that it has something inside it, maybe a hamster or a gerbil, throwing it off balance.  You might be able to access the squirrel cage fan from inside, and definetly from the outside albeit with more sheet metal screws to remove and replace and a Chinese style puzzle to solve.  If you find the squirrel cage fan is broken, they are available on-line.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: New Problem not making the wife very happy!

Reply #9 –
Last spring my rear AC wouldn't blow cold air and it sounded like the unit was trying to fly off the roof. Checked shafts, squirrel cage couldn't find anything. Finally got a small mirror and found the mud dauber nest. Cleaned it and all was good with the world again. Hope you can find something that simple, but it might take intensive looking. Those little buggers can really hide.

Larry
Larry Warren
1996  U320 36' SBID "Lola"
Build #4970
Motorcade #18318

Re: New Problem not making the wife very happy!

Reply #10 –
It sure sounds like the squirrel cage fan outside has mud daubers in it. Our rear ac on our 98 u295 did the exact same thing. Found the nest removed and no more jumping around.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: New Problem not making the wife very happy!

Reply #11 –
I cleaned a bunch of mud Dauber nest out of the both a/c unit smoothed right up. Bet this coach has thirty pounds of nests and wasp nests. My concern are the ones in the intake for the engine.
Scott
Scott and Kim Davidson
If you're going to be dumb, you got to be tough.
DEGOIWKY
Don't ever get old, it will kill you
June 30, 2020
2001 U320 3610 Barn find
Build 5834

Re: New Problem not making the wife very happy!

Reply #12 –
The reason we knew about the mud daubers is because most of us have been there
Rick & Rhonda
2003 U320 4220  Build #6199
Was
91 36' GV 300 Caterpillar, 92 40' U280 300 Cummins, 97 36' U295 300 Cummins, 2002
U320 450 Cummins
(Guess we're hooked)

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