PDA

View Full Version : Red Batt light on Dash ?



lbriant
02-23-2012, 10:09 PM
On the way south for the winter my alternator cable broke off from the wire while driving at night which as you know is a very large cable and it had thrown some flames,
My battery light on dash came on on the dash I fixed the cable drove from oklahoma to arizona with good voltage on my meter and alternator seems to be working fine but my red Battery light won't go out?
any Ideas ? it seems to be different then the box that throws all the other battery warnings like unbalanced etc etc ??:confused:
everything seems to be working fine just can't figure out why that light stays on something must have gotten fried? Maybe a 12 or 24 volt pull down but I can't find anything its driving me crazy cause its probably something simple

garyde
02-23-2012, 11:41 PM
Hi Larry. The only thing I can suggest is to go to the Prevost web site and pull up the dash wiring diagram.

BoaterAl
02-24-2012, 01:07 AM
Larry,
There is a part inside the alternator known as a diode trio. This has failed from a surge/spike when the wire broke. A reliable heavy duty electric service shop can replace that part in your alternator. The hang up will be warranty as they probably insist on a complete rebuild. Thus, it will be your call. Based on your mileage would-be factor to consider a rebuild.
If you take the alternator off yourself be sure you disconnect the battery while removing the alternator from the bus.
AL

lbriant
02-24-2012, 11:22 AM
Thanks guys I was wondering about that? cause I could not find any other circuit outside the alternator,
I have about 75,000 miles on the coach I would not think it needed to be rebuilt yet? but the line definitely went to ground a few times before I got pulled over, then it was at night and I did a rear engine start to see if I could see any problems and it threw about a 4" flame from the wire to the alternator wow easy to spot then :)
How much should a rebuild cost?

BoaterAl
02-24-2012, 01:25 PM
I looked at your info but your location is ..midwest ? You don't say if your able to R&R yourself.

As for 75 K miles that is not a lot. But keeping mind the alternator was subjected to extreme service and it survived without catching fire. You are a lucky guy. I have been thinking about your rebuild and if it was my bus, I would remove and have it completely rebuilt. On that repair you will know it's 100 % when reinstalled, and not subject to any failure in some out of the way location.

Get the model and mfg on the alternator and make some calls to the truck shops. After a few calls you will probably get enough info that tells you where most heavy duty units are rebuilt in town. As in most repairs reliable, trustworthy shops have a reputation in your area.
Prior to disassembly shops usually bench test for performance prior to rebuild then again after.
Good Luck,
AL

lbriant
02-25-2012, 11:52 AM
Yea you were right on, I found a shop he said the same you said, so I pulled it out last night,
It was still close to 80 deg down here in AZ. wow that is one big sucker, I was alright removing the two oil lines on top but real surprised to see the 2 or3 in. line coming out of the bottom !! That was a real burger !!
And I must really be getting old when I pulled it out I thought it weigjed about 300lbs .)

Coach Pro LLC
02-28-2012, 01:48 PM
if this is the large Delco 24vdc, I think a DN 1500, there is an update from Prevost called "Alternator support bracket" that will hold the cable in place and prevent the end from vibrating and eventually cracking. It is a simple metal stand and plastic clamp arrangement and they should be in stock.

BrianE
02-28-2012, 09:02 PM
Larry,

I just recently went through the adventure of replacing my 50DN alternator. Suggest that before you have it rebuilt you contact Penntex in Ft Worth. They have an air cooled replacement for the alternator that eliminates many of the problems inherent with an oil cooled unit. Their tech support engineer can advise you on and sell both styles so they have no axes to grind. If you have a replacement cost before you get an overhaul estimate you will have a choice as to which is the best way to go. http://www.penntexusa.com/PX-8a.htm

Coach Pros advice on the Prevost cable support is a must IMHO. Also there is a Detroit Service Bulletin 18SP527 which should be complied with before reinstalling an oil cooled unit. The purpose of the bulletin is to prevent excessive back pressure in the alternator that can cause leaks and blow out the shaft seal. See attachment.

lbriant
03-01-2012, 12:07 PM
I guess my alternator doesn't have the diode treo inside it,
Found out after pulling it and delivering it :(
Still need to check the voltage regulator ans I belove the bottom small wire might go to a.relay or somthing
And yes I have seen the bracket on another bus mine might have had one once attached to the back plate there is a small broken bracket or dog eared piece of metal I can fix that myself .
I am going to install it today and take it over to the shop to try to isolate the problem ?
Everything seems to be working correctly, the battery light just will not shut off
model number 1117863
type 20
series 50 - d n
serial number 98 k 30
delco remy
270 amp
24 volt

lbriant
03-01-2012, 12:16 PM
Sorry about errors using my phone for internet right now.

jack14r
03-01-2012, 01:01 PM
I have had 2 different wires break at the terminal,check all wires closely.

lbriant
03-19-2012, 10:24 PM
Man guys I just put the big hog alternator back in, If I can get this fixed myself I think i will save just about enough money for another back surgery.)
everything tests out good but that dang light still stays on the dash ??????
no one around here knows anything about the 24 volt 270 amp deco remy series 50 dn model number 1117863
Help Help Help
I think it is probably something simple, one guy said the single small bottom wire on the alternator goes to some kind of relay or fuse but I just lose it in the wire loom? he said it could also be the voltage regulator which is very small and mounted right on the back wall with 4 bolts But it has to be tested with the alternator on a big enough machine to make it work?
I did replace my 600 volt alternator wire and updated it with a bracket so this would not happen again all from the local welding supply store.
any sure fixes out there?

grantracy
03-20-2012, 06:26 AM
I have been having a similar problem,although mine would flicker and then stay on , like a bad ground. Stopped at prevost jax and after a bunch of trouble shooting concluded it was the Vanner battery monitor. I called to order from Vanner supplier but it is currently back ordered so until I replace it won't know for sure.

JIM KELLER
03-20-2012, 09:42 AM
Granville, Are you referring to the Battery Balance light in your above post.

lbriant
03-20-2012, 08:18 PM
Yes everyone I have talked to says there has to be a fusable link in the wire between the alternator and the red Batt, light on the dash, you can make the others on the Batt monitor flicker just by wiggling them a little from small amounts of corrosion,
I get 24 volts on my in dash volt meter up front when I start it it goes to 28 same as I read right off alternator?
I need a wiring diagram I think????

grantracy
03-21-2012, 12:06 PM
no, its just a battery symbol that glows red,intermittingly


Granville, Are you referring to the Battery Balance light in your above post.