Inline fuses & fusible links

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ppeters914
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Inline fuses & fusible links

Post by ppeters914 »

Finally doing the GM alt conversion, but my anal-retentive self just has to research the crap out of everything before lifting a wrench. My question now is:

I am going to run the alt output through a 30A inline fuse, and then into the stock white wire, which, according to everything else I read, should allow the stock ammeter to work without doing double duty as a fuse. Is that correct?

The other thing I read about was putting an inline fuse or fusible link between the starter (+) terminal and the wire going to the wiring harness.

I know extra protection won't hurt, but is this second fuse/link necessary? According to the wiring diagram, this wire from the starter already goes to the fuse box, sooooooooo.......

Comments and other illuminating ruminations appreciated.

Thanks.
Pete
-------------------------------------
'67 1600 - frame off started in 2014. Now I know why roadster projects take so long. What a stupid idea. :smt021
'66 1600 - parts car
'66 WPL411 ***SOLD***
A couple of Porsches, a RAV4 Hybrid, and a motorcycle
TR

Post by TR »

Hey Pete,

This is the wire that causes all the fires in roadsters. It is bundled with the dash harness and the return line from the amp gauge is also in the same bundle. This leads to a lot of heat and 30+ years later, the insulation fails...

So, at a minimum, I would add the fuses where you indicated, between the alt and the harness and between the load side of the gauge and the harness. But truthfully, I would run a new line to the gauge and back to the fuse box. That will save your car and the hassle of having to rewire the charred dash...Fusing the line into the car may save your fuse box or the wiring if it has an issue...

You can also run "extra" items (fog lites, electric fan, etc.) and route them around the gauge so the load in the gauge is limited...TR
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ppeters914
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Posts: 3125
Joined: Mon Jun 28, 2004 5:51 pm
Location: Lake Forest Park, WA (just north of Seattle)
Model: 1500/1600
Year: Low Windshield-64-67.5

Post by ppeters914 »

Interesting. Car-B-Qs are/were common amongst 914's (70-74 models have the battery tray directly above the fuel pump), but this is the first time I've heard of it in regards to roadsters.

Thanks for the heads up. Just one more thang for the To Do list.
Pete
-------------------------------------
'67 1600 - frame off started in 2014. Now I know why roadster projects take so long. What a stupid idea. :smt021
'66 1600 - parts car
'66 WPL411 ***SOLD***
A couple of Porsches, a RAV4 Hybrid, and a motorcycle
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spyder
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Post by spyder »

I replaced the alternator with a gm part years ago, mainly to keep up with the stereo, and in the process realized the wiring in the car would not carry the load. The stereo amps connect directly to the battery. So along with the stock wiring harness I ran a separate wire from the alt. to the battery. 8 gauge I think. So the alternator gauge no longer moves off zero amps but todays alternators are pretty reliable. I'm on my fourth gm alternator, a good choice buying an Autozone lifetime warranty, because the engine spins them too fast. The small fan blades fracture and fly off. One fan blade disappeared, another one "found" the radiator hose. This most recent one I retrofitted with the Datsun pulley to slow it down. So far ............
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