a new alternator and now it doest start

[MuleMac01]

hmmm guys i need some help i replaced my pasager side alternator because it was cooking my battery so i replaced it and put all the wires the way it was ... and then removed my Air intake to replace the rubber hose to the fule injection pump put everything back together even the grounding straps the way it was. Then i put the batterys back in ,,top most frist . ok no sparks... then the lower put the + on then the - then a big spark happend then i saw smoke coming from the terminal board or from behind it this is prob a bad sign can someone help?

 

[Warthog]

Where did you get the passenger alt? Are you sure it is an isolated ground?

If it was rebuilt it is possible that they forgot to install the fiber washer on the ground terminal.

We need more details about the alt.

If the isolated ground is not correct then you have a direct short and you will see fireworks.

 

[MuleMac01]

got it off ebay this one M1008, M1009, M1028 CUCV ALTERNATOR 12V 1105500 OE 100A : eBay Motors (item 160200848047 end time May-09-10 11:11:26 PDT)

 

[mistaken1]

Sounds like it was not an isolated ground alternator.

When buying a CUCV alternator always check for continuity between the ground terminal and the case. If you have continuity and it was sold as an isolated ground return it immediately (or take it apart and modify it into an isolated ground).

 

[Warthog]

You are the second person I have talked to in the last week that has had an issue with this alternator. I wonder in the person who is building them is new and is "forgeting" to install the fiber washers on the ground terminal.

Do you have a Ohm meter and know how to use it? If so, disconnect all the wires and check the resistance between the case and the ground terminal. It HAS to be an open circuit.

You can remove the alternator and split the case to see how it is setup. It may void the warranty.

 

[joeypushjr1]

warthog you might have been talking to me . i had the same thing happen i had the iso installed but im still getting a bang when i hook it up i dont know what is proper as to how it needs to be installed i can open it up and or take that fiber thing off but how would i know its right. where on inside does this fiber washer need to be. and how should it be hooked up inside as well .

 

[Warthog]

First check for continuity between the case and the ground terminal on the alternator. If it is not an open circuit then you need to open the case.

Download the TM 9-2320-289-34 manual from the Resources section or the CUCV Wiki.

Section 4-2 covers the disassembly and testing of the unit. On page 4-4 ther is a diagram of how the washers should be installed on both terminals. Items #25 and 30.

I have included this diagram and how the alternaors should be wired.

Let us know what you find.

Right click on the thumbnail and choose "Open Link in New Window".

 

[joeypushjr1]

thanxs bud ill do and see if the is indeed the issue. i have that wireing diagram but not the alt one thanx. will let you know..

 

[joeypushjr1]

ok im going threw all this im so sorry i must be just frustrated by all ive done on this truck this week but 4-4 is a current and voltage regulator thing im not seeing this diagram on 4-4 and that # 25 and 30 man i wish i knew allitle more on this system . im good on automotive stuff great . but my weaknesses are tranys and well now this altenaor stuff.

 

[joeypushjr1]

oops wait told you its a long week you meant page 4-4 not article 4-4 hehe but still who knows.. ill figure it out . lol

 

[Warthog]

Here is the Ground terminal with some color.

yellow - the terminal bolt
gray - housing/case
purple - rectifier bridge
red - fiber washers for isolated ground.

There are also fiber insulators required for mounting screws 18 and 22 per the tech manual

In a regular alternator the rectifier bridge is grounded straight to the case and there is no yellow bolt. For the CUCV 24v system to work, the passenger alternator MUST have the insulated ground bolt.

Here is the DelcoRemy Service bulletin for the regular 27Si alternator. Notice that the rectifier bridge is mounted with ground screws.

http://old.steelsoldiers.com/index.php?module=pagesetter&type=file&func=get&tid=1&fid=file&pid=256

 

[joeypushjr1]

hahaaha , well yesterday i got mad at the thing so i took matters into my own hands and took what everyone ive talked to into concideration, finially with some of you guys help found the TM i needed. so heres how my day yesterday went......

well first tested iso ground stud to case closed circuit. not good . and decided against my better judgement opened a brand new alt. but good thing i did. it all went better from there. and now relising i wasted 50$ taking it to a shop that supostly builds these thing for a living told him that circuit had to be isolated. so what he does is drills one hole and it was just big enough to slip stud threw. and that was all he did 50$ later what a joke. so i mad hole bigger. big enought to slip a peice of ruber hose to kep it insulated and from hitt walls. left it out and kept searching. after constant countitunity checks i took out the block in there. and relised the gound side of the that block didnt have the plastic protective insulating block under that side and it was resting right on the case of alt. not good so i went looking threw garage and shed wondering what to do . well i had a rubber coated gasket making kit. hehe. so i made gaskets. for the end peices. and fit them on there to insulate it from the case . awsome it worked . now still getting a closed ciccuit, weird. so i then found that cause the block where the 2 prong plug . plugs into has a metal base. crap . well the 3 mounts on it to the case had to be fixed so again i made gaskets to fix it . haha now my circuit is now open. good to go put all back together. still from stud to case open awsome. installed checked batteries. from 12.1v back 12.8v. both 24.2v started up truck front 14.2v back 14.6v both 28.4v awsome i did it. i swear sometimes you have to rely on your self to get anything done i tell you that shop i went to ill NEVER use again i wasted ,money there what a joke and im going to complain to them to let them know it to .. again thankyou to everyone i talked to and the guys that gave me a direction to go and what TM i needed. to me those things are hard to navigate but its just me . again THANKS guys .. i love this site. im a commerical industrail electrican but when it comes to cars and trucks ive never worked on trannys and alt. systems . there just complicating to me but i know know a little more on the alt. systems on these CUCVs . thanks guys ..

 

[mistaken1]

Good news....now to find out what smoked......

Oops! Wrong person.

 

[Warthog]

Great Job.

See, even the shops don't understand what they are doing.....

All that is required for the "isolated gorund" is a few washers that separate the case from the internal electricals.

Thats all it is.....................nothing "special"


My local shop can build me some out of the old '80s big case Caddilac alternators. Drill a hole, add a few washers, install a ground stud and your in business.

 

[joeypushjr1]

thats pretty much alll i did but with gasketts. didnt have any of those washers.