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Topic: It broke 5 hours into ownership... (Read 3617 times) previous topic - next topic

Re: It broke 5 hours into ownership...

Reply #50
 Ended up being $2800 in parts and 42 hours of labor.  The previous owner paid $5000 on the bill and I covered the difference .Flew to WA Friday and picked it up.  Had to be back at work at noon on Sunday.  Started having a charging issue in the middle of Wyoming.  One alternator belt was gone and thought the other was slipping.  Threw 2 new belts on it and had the same problem.  Got fuel in Cheyenne Wyo and checked for lose cables.  One was kinda loose so I tightened it and kept trucking.  It would charge 13v then 11v.    Sometimes it would alternate every five minutes sometimes every five seconds.  Made it to Salina Kansas before the gauge showed a constant 11v.  Only show 9v when I got to the house in Wichita but I made it.

Re: It broke 5 hours into ownership...

Reply #51
You need to diagnose the problem.

Multiple belt failures:
Bad bearing in alternator.
Remove belt and turn  pulley by hand-- check for roughness or tight bearing or play.



Electrical failure:
Start by verifying all connections at alternator and battery isolator are OK-- particularly the small gauge sense wire.
Then we can walk you through troubleshooting the alternator/isolator, as either can give exactly the same symptoms.
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: It broke 5 hours into ownership...

Reply #52
Your Detroit 6V-92TA should have a direct drive double pulley at the rear of the engine with two pretty short belts spinning the alternator. The alternator moves and then is tightened like many automotive alternators. No tensioner/idler or anything. It's accessible right below after you raise the bed and put a stick in to hold it up.

Check all connections to make sure wire/fitting corrosion or fatigue is not the cause. Check isolator and wiring.

Removing the alternator is a five minute job after you disconnect the engine batteries. Best way is to just take it to a small electric shop in your hometown. They can change brushes and put new bearings in as well as servicing the built-in regulator. The charge should be about $100 unless all the diodes have to be replace and then not that much more.

Install the new belts in pairs with Gates Fleet Green Stripe belts as my recommendation. Tighten the belts so you can just turn each 90 degrees mid span with your fingers. Too tight ruins bearings, too loose ruins belts. Check tension a few hundred miles after replacement. It's raining or I would get you the belt part numbers.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: It broke 5 hours into ownership...

Reply #53
Here is a typical U300 alternator with integral regulator as shown when we purchased our U300. You can see the belt adjustment on the top with the long fastener for the pivot point just out of sight on the bottom.

Note the second wire under the minus (-) terminal on the left. You can also see the white tape with the code on it (if still visible and not faded). Smart camera foto this so it goes back on the same way. No idea why they used red for the minus/ground cable.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: It broke 5 hours into ownership...

Reply #54
There is an alternator shop on Douglas just east of downtown.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: It broke 5 hours into ownership...

Reply #55
Should you lose an alternator you can use the generator with the boost switch activated and let the house charger get you home.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: It broke 5 hours into ownership...

Reply #56
Glad you got home  Sounds like the seller is a good guy. 
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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Re: It broke 5 hours into ownership...

Reply #57
Did you rebuild the entire engine ? What was the scope of the repair?
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

 

Re: It broke 5 hours into ownership...

Reply #58
New exhaust manifolds, remaned Turbo and Blower, front axel oil seal, and some other small parts like filters and oil and whatnot.  Borescoped the engine and all the cylinders looked good.  Wasn't worried about it much.