BJ7x Fusible Links...24v tech.

[coldtaco]

Sorry for the hijack.
Hey Stone, I got a electrical emergency and need to talk to Sheldon, the phone numbers I have for him are no longer any good. Can you call him and ask him to call me? Maybe you can help too. I was taking the brushes holder off of the top of the alternator without first disconecting the batteries and the wire on the big post touched the alt and welded to the brushes cover. Now I can't find a fuse that has blown, something has to have blown. My number is 907-490-2445 and email is flyc46@gci.net. It's sunday night at 6pm AK time. Thanks. Stephan

 

[Stone]

Ouch! That's a pretty dangerous thing to be attempting with your batteries hooked up! Quick look at the FSM says there's a 7.5A CHARGE fuse hooked up to the regulator, and there's also a 15A ENGINE fuse. There's also a fusible link by the battery bank...maybe check those out. What symptoms are you experiencing?

I'll forward your message to Sheldon. Good luck.

 

[coldtaco]

Hey Stone, where are these located? I could not find anything in the fuse block on drivers side. At least nothing that is blown.

 

[Stone]

As far as I can tell, those fuses should be in the main fuse box inside the cab, and the fusible link should be one of the ones near your batteries.

 

[coldtaco]

The big $60,000 question is how do you tell what's a fusable link? I was able to talk to Sheldon last night after he got home from work. I hope I can get off work early enough to try and find what I think is a fusable link to replace a wire that got smoked, probably the fusable link?

 

[Greg_B]

The big $60,000 question is how do you tell what's a fusable link? I was able to talk to Sheldon last night after he got home from work. I hope I can get off work early enough to try and find what I think is a fusable link to replace a wire that got smoked, probably the fusable link?

This is a fusible link off a BJ42. The wires that are covered in the black insulator are the fusible portion.

hth's

gb

 

[wesintl]

I replaced the fus link on the 70. It's right off the + to the first green connector (black goes to a little Stud terminal) there are 3 fusible link wires. I can take a pic if you need. YOU will know if they burn because they will smoke.

even with my electrical fire storm the fuse link didn't burn though all the way and I could still get enough juice to crank. The Fuse link is availble in the US sytem and is only like $7. I can post the #'s tonight if you need them

 

[wesintl]

https://forum.ih8mud.com/showthread.php?t=55954&highlight=fusible+link


the search tool always comes through...I thought it was here somewhere

 

[coldtaco]

Wesintl

Yeah, that is what I thought it was. The smaller wire coming out of the green thing is what smoked. The other wire is in pretty bad shape too, about broke through. Will have to see if I can get it apart to replace those wires. The parts stores here have these, but they are not given any kind of rating, just wire size, so hopefully they will be the right size/rating. Will have to try the part number when I get a chance. Thanks.

 

[wesintl]

Yeah, that is what I thought it was. The smaller wire coming out of the green thing is what smoked. The other wire is in pretty bad shape too, about broke through. Will have to see if I can get it apart to replace those wires. The parts stores here have these, but they are not given any kind of rating, just wire size, so hopefully they will be the right size/rating. Will have to try the part number when I get a chance. Thanks.

That's why I ordered a new fusible link from toyota. Trying to figure out the rating was too much. Your dealer might have just the wire too. I think mine did but I opted to wait on the whole new fuse link. I almost bought 2 for the next time, but I didn't want to jinx myself I probably have half a dozen from 60 links I could pull a wire from if needed. The 60's won't work because the connection is different.

anyway good luck.. I at least I got the number good for you

 

[coldtaco]

Update. Well, I replaced the two fused wires coming out of the green connector with generic fusible links based on wire size for a temporary fix. I got a new connector/with fusible links on order. Everything is back on power wise, but I don't think The Alt. is charging. I hooked a volt meter to the 24V pos. terminal and turned head lights on and the voltage started at a little above 24V but it kept creeping down. Is there something I need to do still? Or is the voltage regulator now fried? Any ideas? Thanks.

 

[coldtaco]

Finally got to work on the alt again, had to go out of town. Before leaving this afternoon for a test run, I was getting about 27.4V on the volt meter between the 24V + terminal on the battery and a ground. As soon as the garage heats back up I will check it again to see if its back up around 28V where it should be according to what I know about 24V systems. On a positive note, I did not notice any lights going from normal bright to dim and back and forth and no volt needle fluctuations.

 

[Voostra]

Could be wrong here - but I think that is fairly normal after you replace the brushes - takes a little while for them to wear from new (square) to rounded so they make nice contact, for that time you get a bit of funny behaviour.