New alternator, oil, tires and a big story

[Roughstock]

Hi there,

This should be the wrap up. Went to the dealer again yesterday.

@Helipilot @pk9394, @JohnGalt this should make sense now. Thanks for posting before, it is good to figure it out correctly.

The service manager had a bit of disconnect between him and the mechanic. Also, they don't do winches there so he would not be familiar with Ford's winch instructions.

When he got the part with the fuse blown he thought it was the part connected to the battery. You can see why. Pretty similar.

The actual location of this part is here.

Attached the fuse box. It is called a 300 amp fuse or something like that $240.00.

This is a picture from the Bronco they took the part out of while my part came in to get me up and running. It was sitting waiting for the install of the new fuse.

I connected to the second from the right in this pictures below since we didn't have a nut to fit either of the two empty pegs/bolts. Those two centre leads are connected to the alternator and the starter.

So it seems when the alternator kicked in while winching it blew the 300 amp fuse located in the picture above by the fuse box. Also, the alternator worked intermittently since the fuse break wasn't huge. When it was cold it was touching and as it heated up it separated - so it seems.

Here's a close up of the fuse. I believe the larger fuse will be for the alternator since they figure the alternator when running full could be about 250 - 300 amps.

In the end it was an expensive "nut". A tow, a hotel, a new part and labor. All good, glad I wasn't remote when everything failed. My wife and I decided to stretch the winch rope in remote mountain top road. Right at the top. Not many go by there. That is where it seems it blew.

 

[Bschurr]

Hmmmm - I was under the impression that the positive (and negative) threaded leads next to the battery terminals were each “bussed” together.

I guess that is NOT the case since you are being told that your winch was connected to the threaded terminal that the alternator is connected to and when the 2 were used together, the amperage exceeded the 300 amp capacity of the fuse.

I am not saying that the mechanics who fixed this are wrong but this seems a bit “off” to me.

If this is truly how it is all wired together, there should be some indication, notice or apparatus to preclude this use case because clearly, this can become a significant issue.

 

[Roughstock]

Hmmmm - I was under the impression that the positive (and negative) threaded leads next to the battery terminals were each “bussed” together.

I guess that is NOT the case since you are being told that your winch was connected to the threaded terminal that the alternator is connected to and when the 2 were used together, the amperage exceeded the 300 amp capacity of the fuse.

I am not saying that the mechanics who fixed this are wrong but this seems a bit “off” to me.

If this is truly how it is all wired together, there should be some indication, notice or apparatus to preclude this use case because clearly, this can become a significant issue

It seems the the outside right bolt, when facing the battery, does not have a fuse attached to it. That is why Ford's instructions for their winch tells you to put it there. As well, the far left lead may be the same. You can see there is no fuse on the part.

This is what I came up with, it may be wrong. All I know is it seems likely I blew the fuse connecting to where I did.

 

[Bschurr]

I totally understand what you are saying @Roughstock but, I would think that each the threaded posts all attach to the battery together so any load from any wire attached would all be the same in terms of total amperage load. A fuse protecting the loads attached to the posts would be beholden to the entire load on the battery.

My point is - if the individual posts have unique fuses protecting them then there should be some documentation advising of this and/or a mechanism to preclude overloading them (as you supposedly did). Ford purposefully added the threaded posts and provided additional posts for ease of attachment for additional 12v accessories - i.e. you can’t attached additional accessories to the alternator fused power lead!

 

[Roughstock]

I totally understand what you are saying @Roughstock but, I would think that each the threaded posts all attach to the battery together so any load from any wire attached would all be the same in terms of total amperage load. A fuse protecting the loads attached to the posts would be beholden to the entire load on the battery.

My point is - if the individual posts have unique fuses protecting them then there should be some documentation advising of this and/or a mechanism to preclude overloading them (as you supposedly did). Ford purposefully added the threaded posts and provided additional posts for ease of attachment for additional 12v accessories - i.e. you can’t attached additional accessories to the alternator fused power lead!

I understand now. I agree, if that truly is the case there should be some warning or something in the manual.

At this point as long as I don't have anymore issues I am happy. If someone has some different information I would be happy to listen. I've tried to get to the bottom of it and I'm at the end of what I can do.