Fusible link problems!

[Ky Hillbilly]

Working on a 1977 EB. Not knowing what I was doing! I cut a red fusible link out near the altenator and replaced it with a 30 amp fuse because I thought it looked old. Now when I start bronco and rev it up the 30 amp fuse blows and my volts to my gauges goes up the 17 volts. I actually fried my gauges.

The red fusible link has a 6 g on it. I can't seem to find one at any of the auto stores. Closest one I can find is a 10g at auto store. Is it truly meant for a 6 gauge wire? Can I replace it with a big modern amp fuse??

Also can I rewire and take the gauges and stereo off off the altenator /starter circuit?

I hope I don't sound reduclous! This isn't my area of expertise!

 

[mp]

I just bought a spool of fusible link at Autozone

 

[Viperwolf1]

You need a 16g fusible link.

 

[broncnaz]

You can use a larger fuse in the wire Id say 50 amp maybe 60 amp max. As the alt will put out more than 30amps after first starting and that may be frying your 30 amp fuse. I think you may have other issues that are frying your gauges. bad alternator regulator as it should limit the alternator to a max of about 14.5 v. or bad wiring somewhere.
While you can rewire accessories and gauges its not always worth the trouble and extra wiring.

 

[Viperwolf1]

I think you may have other issues that are frying your gauges. bad alternator regulator as it should limit the alternator to a max of about 14.5 v. or bad wiring somewhere.

System is working normally. If the fusible link blows the regulator can no longer sense charging voltage so it tries to raise it and ends up maxing it out.

 

[broncnaz]

Well then he just needs a bigger fuse. 30 amps is to small.

 

[Ky Hillbilly]

You need a 16g fusible link.

I was wondering if it was a 16g instead if a 6g , because I was looking at a wiring diagram and seen that they were using a 16g. I didn't know for sure if that was the same location though.

Thanks

 

[Viperwolf1]

I was wondering if it was a 16g instead if a 6g , because I was looking at a wiring diagram and seen that they were using a 16g. I didn't know for sure if that was the same location though.

Thanks

It is. There's only one fusible link.

 

[DirtDonk]

Early diagrams list two. One at the starter relay end, one at the alternator side of the 3-wire plug.
Never tested that theory, and later diagrams don't show that second one, but the early one lists 38a at the battery, and 37a at the alternator.

Do you think that was a running change, an oversight in later diagrams, or simply a mistake in the early one?

Paul

 

[Viperwolf1]

Early diagrams list two. One at the starter relay end, one at the alternator side of the 3-wire plug.
Never tested that theory, and later diagrams don't show that second one, but the early one lists 38a at the battery, and 37a at the alternator.

Do you think that was a running change, an oversight in later diagrams, or simply a mistake in the early one?

Paul

Only the '70 diagram shows one at the alternator. I haven't seen one on a '70 but then I never looked for one. I do know that '72 and later didn't have one there.

 

[70_Steve]

Only the '70 diagram shows one at the alternator. I haven't seen one on a '70 but then I never looked for one. I do know that '72 and later didn't have one there.

FWIW. My 70 did not have fuse link 37A at the alternator.

 

[DirtDonk]

Not surprised at all this. I think Ford was a bit late getting updates to the printers, as even the Ford Service Manual showed '71 as having the same floor-mounted fuse box and two rectangular firewall plugs as the earlier models.
Even among those early models, I've seen at least three variations on routing and those two connectors.

Still, now that I've got my curiosity all in an uproar, I'm going to have to go out and peel the tape back from my alternator connector to see what mine's got! ;D

Paul