fussing and fighting with electrical after fusible link replacement

[FJ40Jim]

Start troubleshooting from the beginning.
Check volts between 2 batt terminals. Should be 12.x V.

Move - probe from batt - terminal to engine block. Should still read 12.x V.

Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link.

Take voltmeter inside truck to fusebox. Connect -probe to clean ground. Touch + probe to every fuse. Some will show +12v, some will be 0.0 V.

Turn key on. All fuses should show 11-12V. Turn key off.

Report back here.

 

[swelltimes]

Start troubleshooting from the beginning.
Check volts between 2 batt terminals. Should be 12.x V.

Move - probe from batt - terminal to engine block. Should still read 12.x V.

Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link.

Take voltmeter inside truck to fusebox. Connect -probe to clean ground. Touch + probe to every fuse. Some will show +12v, some will be 0.0 V.

Turn key on. All fuses should show 11-12V. Turn key off.

Report back here.

Ok, I worked thru this list, everything confirmed at 12.x V; fuses w key off varied btw 12V and 0.0; with key on, I’m getting ~9V with a ground back to engine block. Same reading using fuse block ground.

 

[Solace in Solitude]

So, this (from Jim’s list) tested good?

“Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link”

If so, I would make sure the connector you added to the pigtail, off the body harness, is properly connected to the pigtail... and that the pigtail is properly connected to the harness.

Your “before” pic shows a light colored pigtail (on my iPhone)... your “after” pic looks like the connector is on a dark colored pigtail... are they the same pigtail?

 

[swelltimes]

So, this (from Jim’s list) tested good?

“Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link”

If so, I would make sure the connector you added to the pigtail, off the body harness, is properly connected to the pigtail... and that the pigtail is properly connected to the harness.

Your “before” pic shows a light colored pigtail (on my iPhone)... your “after” pic looks like the connector is on a dark colored pigtail... are they the same pigtail?

View attachment 1732052 View attachment 1732053

No, new pigtail / link from @Coolerman, and the connections are all good. He sets his customers up for success! I just double checked my work, too.

 

[swelltimes]

Pulled fuse block, cleaned all contacts and fuses holders. Found wide range of fuses- see the values relative to FSM:

 

[Solace in Solitude]

Yep, I’ve bought from Mark many times... his stuff is great!!

I don’t mean to be obtuse... but, I’m still not sure... I’m wondering how the new pigtail attaches to the harness (not the pigtail from the battery terminal) Your “no power” symptoms are indicative of an issue with the fusible link (burned out, bad connection, etc.)...

So, Jim’s test (below) read 12.x V?

“Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link”

 

[Solace in Solitude]

Those fuse ratings look like someone didn’t understand what proper fuse ratings are for... lucky they didn’t melt your harness.

 

[FJ40Jim]

If there is 12V showing at all fuses, then fuse link is feeding the fusebox.

12V to fusebox, but nothing works, leads to thinking there may be a problem on the ground side.
The ground cable in OP's picture is routed wrong and could be a problem. There should be a ground cable from batt. to frame or batt stand right in frt of batt. There should be a ground cable from RH frame rail to starter bolt or engine mount bolt.

 

[swelltimes]

Yep, I’ve bought from Mark many times... his stuff is great!!

I don’t mean to be obtuse... but, I’m still not sure... I’m wondering how the new pigtail attaches to the harness (not the pigtail from the battery terminal) Your “no power” symptoms are indicative of an issue with the fusible link (burned out, bad connection, etc.)...

So, Jim’s test (below) read 12.x V?

“Disconnect fuse link at body harness, probe end of link, should read 12.x V. If yes, reconnect link”

Sorry, I was replying from my iPad earlier, when I was in my shop, so I didn't reply expansively.

The pigtail attaches to the harness with a connector that Mark supplied: I cut ~.5 inches off of the wire on to which I crimped the new fitting.

I have tried jumping the new fusible link from the battery to the harness, to the extent that I reinstalled the original piece of wiring that I removed: the same symptoms of non-starting persisted.

 

[swelltimes]

If there is 12V showing at all fuses, then fuse link is feeding the fusebox.

12V to fusebox, but nothing works, leads to thinking there may be a problem on the ground side.
The ground cable in OP's picture is routed wrong and could be a problem. There should be a ground cable from batt. to frame or batt stand right in frt of batt. There should be a ground cable from RH frame rail to starter bolt or engine mount bolt.

I will check the grounds this evening, and report back.

 

[swelltimes]

Those fuse ratings look like someone didn’t understand what proper fuse ratings are for... lucky they didn’t melt your harness.

Yeah, I was really surprised at the ratings when I was pulling fuses and cleaning things. Similar to when I rebuilt the carb (still don't have that carb dialed in, since the truck won't start), I feel lucky the truck ever ran at all.

 

[swelltimes]

Still no luck after doing these tasks:

• I removed the thin wire from the - batt. terminal to the frame (the thin blue wire in pic #3 in the first post);
• wire-wheeled and cleaned all ground connections, on wires, bolts, frame, starter bolt, and reinstalled with dielectric grease.

A couple of questions / notes after this.

• I have ground wires running from the battery to RH frame rail, from the RH frame rail to the bolt on the starter, and one from the battery to a mounting bolt on the engine block (you can see this in pic #5 in the first post, above the spark plug wire at the front of the engine).
• When I was testing, I left the ignition key on while I was checking voltages, and the + battery terminal was getting hot pretty quickly: is this normal?

 

[swelltimes]

Thinking back on the work that I did earlier to the carb, etc., and made sure I hadn't knocked something out of place. Pulled the gauge cluster (I had to reinstall the speedo cable earlier), but everything seems fine back there.

I'm stumped as to what happended when I replaced the fusible link, and why nothing works now.

 

[spotcruiser]

Have you thoroughly cleaned both battery terminals and clamps? They look pretty corroded in your photos.

 

[swelltimes]

Have you thoroughly cleaned both battery terminals and clamps? They look pretty corroded in your photos.

99% sure that I did, but I'll go do it again. They are pretty rugged, for sure.

 

[swelltimes]

I am a huge donkey.

Took a wire wheel to the terminals, and Emory cloth to the connectors, dome dielectric grease.....and starts, lights work, etc.

I know I did this recently, as there was grease on the connectors, but I was more thorough and aggressive in cleaning.

Thanks for all the help, I’m now going to go hide in shame for a while.

 

[spotcruiser]

That's OK. Stuff happens.

I've seen it plenty of times before, where there was correct open-circuit voltage, but nothing would function because of corrosion at the terminals.

 

[swelltimes]

It's clear that electrical stuff still remains a mystery to me!

A few more questions persist:

• Should I change the fuses out for the correct amperages?
• I wonder why, when replacing the PO's wire with the proper fusible link, I ran into trouble that then was solved by cleaning battery terminals? (This is likely impossible to answer.)
• Does anyone have recommendations for battery / ground cables and connections, ideally a kit with some feet of wire with which I could make up a number of cables?

 

[Solace in Solitude]

s*** happens... glad you fixed it!!

I always run the correct amperage... they are established for a reason.

I bought a kit from this guy and was very impressed with his quality, response, price, etc... I think he’s on MUD, but, really don’t recall for sure. Note: I have no idea of the current price... the transaction below was June, 2017.

“The fj40 kit I sell is all 1/0 wire. I think I would stick with that. The cost is 93.15 payable to mguisinger@gmail.com (PayPal address).

Let me know if you have any questions.

Mark “

 

[spotcruiser]

By all means, install correct fuses in every circuit.