[Tf175]

I am removing the Leece Neville alternator on the 86 with 8V92 . The alternator is mounted above the bell housing and drives off the blower . There are three bolts going through the alternator housing and spacer with cooling vents , threading into the drive housing. According to the Detroit manual the alternator should separate from the drive at the spacer . I have been unable to get it to budge there , however I can get about 3/8 inch movement between alt housing and spacer . There is white sealer between the spacer and drive housing , it's either stuck very well or I'm missing something here . I'm hoping someone out there can shed light on this or point me in the direction of a schematic . The manual that I downloaded doesn't have an illustration of the alternator mounting .
Any information very much appreciated .
Thanks,
Chris

[Tf175]

I am removing the Leece Neville alternator on the 86 with 8V92 . The alternator is mounted above the bell housing and drives off the blower . There are three bolts going through the alternator housing and spacer with cooling vents , threading into the drive housing. According to the Detroit manual the alternator should separate from the drive at the spacer . I have been unable to get it to budge there , however I can get about 3/8 inch movement between alt housing and spacer . There is white sealer between the spacer and drive housing , it's either stuck very well or I'm missing something here . I'm hoping someone out there can shed light on this or point me in the direction of a schematic . The manual that I downloaded doesn't have an illustration of the alternator mounting .
Any information very much appreciated .
Thanks,
Chris

Alternator update ... 12mm 1.25 tap threads right into fan housing , came in from the drive side with 3/8 cap screw as a jack screw and voila ! Alternator came free . I think there should be a gasket there instead of the sealer which had the flanges stuck together. Now to get this greasy lump working ...
Chris

[Tf175]

Leece Neville saga continues . Found information plate indicating the alternator is a factory reman unit by Sheller -Globe , a company defunct since 1989 . Tag indicates alternator is a 14 volt unit with 75 amp output . This is interesting in that the Newell manual states that standard equipment is 160 amp Leece Neville. Search begins for the correct unit.
Chris

[MrE]

Chris, an alternator shop should be able to rebuild your alternator with a variety of output amps, or you can search for them online. Buying online might even be less expensive than having an alternator shop rebuild yours.

[Tf175]

Leece Neville update. Sent alternator out for rebuild and upgrade . Now have a 220 amp alternator,  basically my front housing adapted to a new unit . It has two positive posts whereas the old 3425 J had one . I'm wondering if this is for a Duvac system.  Not familiar with Duvac,  presume it isolates the batteries so the chassis and house batteries can be charged while traveling. I want to be sure this alternator is going to work before bolting it back on .
Thanks,  Chris.

[Richard]

Just one general caution. It is not a good practice to use the alternator to charge heavily depleted house batteries. It is really tough on the alternator.

Yeah, I know, then why are most motorhomes wired to do it that way. It certainly keeps the 12V house systems going while underway, but you really can put a strain on the alternator with house batteries that are way down. The problem is the heat generated by making all that current just causes the alternator to prematurely fail.

This doesn't apply to the rigs with the huge 50DN alternator that is oil cooled.

[Tf175]

Just one general caution. It is not a good practice to use the alternator to charge heavily depleted house batteries. It is really tough on the alternator.

Yeah, I know, then why are most motorhomes wired to do it that way. It certainly keeps the 12V house systems going while underway, but you really can put a strain on the alternator with house batteries that are way down. The problem is the heat generated by making all that current just causes the alternator to prematurely fail.

This doesn't apply to the rigs with the huge 50DN alternator that is oil cooled.

In the beginning I only wanted the correct 160 amp output that the coach came with , but this 220 amp has me wondering about running the electric only refrigerator with an inverter while travelling . We will use the coach for our racing trips and will be running the generator or shore power when parked . I agree that it is taxing for any alternator to bring up depleted batteries. I am curious as to whether or not I can connect the chassis batteries to one of the positive studs and leave the other one capped . I was going to connect this way and then saw something about the Duvac system that has me wondering... 
Thanks for the reply !
Chris

[Richard]

Elec fridge running on the inverter is a minimal current. Fridge pulls about 2 amps at 120 VAC, so 20 amps at 12 VDC times 1.3 for efficiency loss through the inverter. So about a 26 amp load on the alt while the fridge is running. Best I can remember the DDEC and all the other stuff is about 50 amps.

I find very little reference to the DUVAC system, what I do see leads me to believe it is made for rigs that have both 24 and 12 VDC. This is the very first reference to DUVAC and Newells that I recall in ten years of forum membership.

Does your coach have a DUVAC system, or did you just get an alternator with two hot terminals?

[Tf175]

Elec fridge running on the inverter is a minimal current. Fridge pulls about 2 amps at 120 VAC, so 20 amps at 12 VDC  times 1.3 for efficiency loss through the inverter. So about a 26 amp load on the alt while the fridge is running. Best I can remember the DDEC and all the other stuff is about 50 amps.

I find very little reference to the DUVAC system, what I do see leads me to believe it is made for rigs that have both 24 and 12 VDC. This is the very first reference to DUVAC and Newells that I recall in ten years of forum membership.

Does your coach have a DUVAC system, or did you just get an alternator with two hot terminals?

Our coach doesn't have a Duvac system . The alternator now has two hot terminals now , so I did a search about that and Duvac came up . The extra hot got me thinking about charging house batteries while traveling without merging them . 
Thanks , Chris

[Richard]

Some Newells of your era, and you will need to check yours, merged the batteries when the ignition was on. My 95 did that. Newell started adding the battery isolator later.

Simple check. Measure your house batt voltage. Crank the engine. If the house batt voltage goes up then they are already charging.

I did say some Newells. They came from the factory in different configurations, and who knows what wiring changes may have happened since.