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Topic: Replaced several Alternators  (Read 654 times) previous topic - next topic

Replaced several Alternators

I have a 2009 Nimbus (200 Amp) I just installed my 5th alternator does anyone know what is the cause? Seems to last no longer that 5,000 miles. This one lasted only 1,000 miles... Grady5588

Re: Replaced several Alternators

Reply #1 –
Are you installing new units, remanufactured, or having your unit rebuilt? 
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Replaced several Alternators

Reply #2 –
Are they going bad mechanically or electrically??  Hard to advise if we don't know the problem.  Have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Replaced several Alternators

Reply #3 –
No reason for an alternator to fail in so short a time. They should last for years.
Some thing is causing it, I would GUESS that alternator is running hot, either from constantly running at peak out put or lack of cooling. I would start with load testing batteries, if they are low alternator will work at trying to charge them, problems could be cables corroded or loose, dead cell ion batteries, failed isolator.
A good alternator shop should be able to analyze it, test batteries and trace down where the problem is. The shop can quickly tell you if diodes are bad, bearing bad and windings bad.

Gary B

Re: Replaced several Alternators

Reply #4 –
I agree-- find the CAUSE of the problem.

Remove the alternator and have a good alternator shop diagnose the part that failed.  THEN we can help with how to remedy.
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: Replaced several Alternators

Reply #5 –
We too had the same problem with our 2007 Nimbus with alternators.  We had to finally change ours with a brand new one instead of fixing or buying a refurbished unit. That finally solved the problem.

Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: Replaced several Alternators

Reply #6 –
Again, the "what part of the alternator failed" is important to identifying the root cause.
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: Replaced several Alternators

Reply #7 –
Quote from: wolfe10 –
Again, the "what part of the alternator failed" is important to identifying the root cause.
With our 2007 Nimbus, we lost the diodes each time. Once it was repaired and the second time the diodes went out on the refurbished unit. Knock wood - third time was the charm.
Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: Replaced several Alternators

Reply #8 –
Check for loose connections---- any arcing will cause voltage overshoots that will zorch the diodes in the alternator every time.  Switching batteries with a manual battery switch ( if you don't have the diode isolators) with the engine running will do the same thing unless your alternator is equipped with a surge suppressor.
Per Brett, you really need to know the failure mode on your alternator to know what to look for.
Current coach 1996 U320 40'
Previous coach, 1990 36' U280
 

Re: Replaced several Alternators

Reply #9 –
By the way, ZORCH is a technical term, it's what happens when you let the magic smoke out of an electrical device.  :))
Current coach 1996 U320 40'
Previous coach, 1990 36' U280