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Topic: Alternator Retired. (Read 978 times) previous topic - next topic

Alternator Retired.

Well it is just our luck started the coach and noticed showing only 12 volts well bull butter. removed the alternator took to the shop, It tested bad now the wait is on for a replacement. After looking at the battery isolator and related components, things look pretty rusty and a possible overheat of the isolator at one time. Thinking about replacing all just trying to figure out what to order as far as solenoids breakers fuses ect. Any info would be greatly appreciated. Thanks in advance and MERRY CHRISTMAS.
Craig Wickham
1997 U295 36 Ft.

Re: Alternator Retired.

Reply #1
Craig, Try cleanup of posts and cable ends first, probably nothing wrong with isolator. I subscribe to the " if it ain't broke, don't fix it " theory.
AND..... Remember , you have a unique Alternator, ask the tech that rebuilds it if he understands a  FOUR WIRE, REMOTE SENSE type.
Good luck  and MERRY CHRISTMAS

Gary B

Re: Alternator Retired.

Reply #2
Rusty and corroded connections are like kinks in a garden hose. High resistance raises temperatures at the connections and may reduced the overall current handling capacity. If you can't read the codes, label the cables before you remove them. Make sure to disconnect the battery and only do one at a time as a good percentage of owners will replace in the wrong order. I like to flatten the ends of the larger cables so they present the maximum surface area against the fasteners. A flat file works well. I would clean things up before replacing everything. I have seen MUCH worse than yours.

As you can see, this was not the brightest engineering feat locating the panel where they did.

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

Re: Alternator Retired.

Reply #3
Couple things you can easily check.  The original alternator is called a Duvac style.  It has a remote sense wire that adjusts the output level and it has another wire that provides an excite voltage, this turns the alternator on when the motor runs. 

These are the two smaller wires that were disconnected when the alt was removed.  If you put your meter on each wire in turn, both of them should be hot when the key is turned on (other meter lead to ground.)  When the key is turned off one should stay hot, and one should not be hot.  If the excite wire does not switch on with key, your alternator won't be turned on either. 

If you don't want to order an exact replacement alternator, here is the original factory instructions on how to convert almost any Leece Neville (Prestolite) alternator to Duvac.  Save you some time and $.  Prestolite - Leece Neville
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Alternator Retired.

Reply #4
What is the object (to the left of isolator) that looks like a old 12v ignition coil, and the 2 round objects below it?  Haven't noticed those in other isolator panel photos.  Just curious...
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Alternator Retired.

Reply #5
Chuck, the log round container left is the AC dryer (by the looks of it) and below is possibly a solenoid
Thats my guess anyway.
Craig, other possible items on that board can be a/c circuit breaker (small3/4"x2" metal cased thing) and possibly a relay also A?C. If you have a chance take a closer pic of it showing more detail then we will know for sure.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Alternator Retired.

Reply #6
Chuck,

The 2 round things below the A/C dryer look like the solenoids on his rear HWH 6 pack. If you look real close on a big screen you can see some more of what appears to be the wire loom. They are just behind the isolator board. I have seen a couple of coaches that the manifold is located here rather than on the other side.


Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Alternator Retired.

Reply #7
[quoteI subscribe to the " if it ain't broke, don't fix it " theory.][/quote]

Wish I had Gary telling me that a few months ago. Thought I would have the isolator checked while I had the alternator rebuilt. Got to the last bolt and it twisted off. Doh!  Went ahead and took it down and the rebuilder tested it and said that it had been real hot and was starting to fail. I think that he just made that up so I wouldn't feel bad.  Also... after I had the alternator rebuilt, and new isolator, I put it back on and all I could get was 12 volts. I tested everything and was at the point of taking it back off when I tested a circuit breaker mounted on the wall right (pass. side) of the isolator.  It was hot on one side and nothing on the other side. I replaced the circuit breaker and low and behold, 14.5 volts. 
Bruce & Teresa
2000 U320 4010
2015 Jeep Rubicon

Re: Alternator Retired.

Reply #8
Craig,

After looking at your photo the isolator epoxy looks like it has been bad hot. There are plenty of discussions over the pros & cons of using an isolator and whether to replace or not. The big thing that needs attention that pertains to the alternator system is your breaker that is mounted on the isolator board. I see your sensing wire is still landed on this breaker. As bad rusty as the breaker is you may be getting a bad voltage indication back to regulator. A $3/ 20 amp breaker from any parts store will help. There is also several discussions as to whether this is a good place to land this wire or should it be moved to the battery post. Either place the wire end needs to be clean so the voltage  reading is good. You can do a quick search for both.  Merry Christmas to all!!

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Alternator Retired.

Reply #9
Craig,

Also one of your relays must have died at some time in the past. It appears that the wires have been pulled off and put on a new relay that is hid in among the other wires rather than mounting on the wall. This don't have any thing to do with the function of the alternator but if I had all the wires loose I would remount the A/C relay in it's proper spot so it won't get tangled up in something bad. One of those relays control the condenser fan & the other the compressor clutch IIRC.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Alternator Retired.

Reply #10
P &M, I agree with your asessments on relay and circuit breaker as in my post I just mentioned about them being there. To me it is an automatic replacement of all those items due to age and location and what I have done on other GV's.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Alternator Retired.

Reply #11
Has anyone looked into using one of the new Bosch HD alternators rather than using a replacement L-N? 

Bosch introduces 'Long Haul Extreme' alternators

If I was replacing the isolator, I'd be looking to something different than the diode based factory unit, something more towards the Sterling isolator.

http://www.sterling-power-usa.com/ProSplit-RZeroVoltDropMarineBatteryIsolator-9.aspx
Robert
Build # 5304
1998 34' U270 Cummins 6CTA8.3

Re: Alternator Retired.

Reply #12
and if you go the Sterling route do not forget we have a member who sells them and I think you can get a slight discount from him as a member. I have the Sterling charger and finally just getting ready to install it and take Isolator out.
alan@baymarinesupply.com
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Alternator Retired.

Reply #13
John,

Please post a full report on that Sterling unit after you have it going.

P & M
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Alternator Retired.

Reply #14
 will do as soon as I get it in. I am going to make a semi cover for it as am mounting it where the Isolator is(under bed) in engine compartment and as there will be some moisture there I want to protect it but not stop a flow of cooling air. This due to holidays etc may take a week, we will see.
johnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Alternator Retired.

Reply #15
If I was replacing the isolator, I'd be looking to something different than the diode based factory unit, something more towards the Sterling isolator.

http://www.sterling-power-usa.com/ProSplit-RZeroVoltDropMarineBatteryIsolator-9.aspx

I replaced isolator with this, and wired in the optional switch. Combiner 160 Sheet
1998 U270 34'

Re: Alternator Retired.

Reply #16
Geewhiz John, hurry up! I just got my new one from Alan yesterday, And I want you to be the guinea pig! LOL, I am glad it's not a race...
Don
will do as soon as I get it in. I am going to make a semi cover for it as am mounting it where the Isolator is(under bed) in engine compartment and as there will be some moisture there I want to protect it but not stop a flow of cooling air. This due to holidays etc may take a week, we will see.
johnH
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Alternator Retired.

Reply #17
Our isolator was in the same wonderful location except that the floor safe was installed about 3 inches to the street side of it. Lots of fun with any cleaning, rewiring, replacing. Makes me wonder if the "under the coach" guys and the "inside the coach" guys ever got together to discuss this kind of location thing. Of wait, maybe they did. A Merry Christmas to all ^.^d !
Larry
1996 U295 36'
Build # 4805
Actually we sold it but just like to lurk

 

Re: Alternator Retired.

Reply #18
I just helped my son install a second battery in his Lincoln Town Car and we used the 200A Cole Hersee 48530 Smart Battery Isolator:

http://www.colehersee.com/assets/files/hotfeeds/1307737555-D-617_SmartBatteryIsoHF.pdf

This has been working great. It has connections for a remote boost switch and a remote indicator light. Looks like it should also work well in an RV application.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B