Tackling a full rewire on a 67 and a few other things too

[RiverPatrol]

That's right, this is the one with the after-market A/C added. Well, there's your electrical drain, guaranteed. And that unknown thing by the fuse block is for the A/C as well, I imagine. I would also venture to guess that the red wire/s that have been added to the fuse block are for the compressor. That's why the compressor trigger works with the key off, and that is your drain.

Does the A/C even work? You may just have to put up with the drain if you want to keep the A/C. The only other Patrol I saw with A/C had electrical problems, too. I yanked the A/C out to solve the problem.

It's not unusual for the fuse block to have the spot without a fuse. it's just always hot there. Lights working without the key on is normal also. As I recall, about the only things that won't work with the ignition off are the wipers and turn signals.

The nut under the horn isn't supposed to be a castle nut. this might be why you can't get the horn to work when it's assembled - you can't push the button in far enough to make contact.

Interesting that the clutch/throwout didn't make any noise. I can't remember a throwout bearing only deciding to make noise sometimes. Usually it's always.

[Cameron110]

Day Two update:

Family time meant only some time to work on the rig today but we did get some things done.

We sorted out the horn switch by swapping the incorrect castle nut for a shorter standard nut and took the opportunity to re-clock the steering wheel correctly. The relay worked well when bench tested. When we bench tested the two horns both worked. We checked all the wiring legs and everything was ok. Then hooked up all the parts, popped in a fuse and only the high tone horn (same side as the fuse) worked. We then spent a bunch of time retesting the wiring in the harness ultimately finding like 40 ohms of resistance going over to the far (low tone) horn. Then we jumpered the relay to cut down voltage loss on the way to the low tone horn, we even tried again with the truck running and the battery on a 6a charger to rule out voltage drop from the resistance in the final segment of the wiring. None of that helped and it was time to get ready to go to the BBQ so We walked away for a bit.

Back at it in the afternoon I decided to spend some time checking out the existing wiring and figuring out what had been hacked and where. Pretty quickly I found that despite the truck being a 67 the wiring matches the 66 diagram. Things matched up pretty well once I figured that out. Then I had a bit of an epiphany, I pulled the low tone horn and bench tested it again.... Dead. I guess I just needed a reminder that when working on old stuff retesting everything is sometimes the fastest way to a solution as anything can fail at any time.

I have a few more questions that I couldn't figure out from looking at the truck and the diagram.

I assume, having looked everywhere else I can think and not finding anything else that could be it that this is the brake light switch.


Looking at the diagram it should be normally open and then close when brake pressure is applied. In testing it is open all the time reguardless of pressure in the system. I'll recheck it in the morning but I'm thinking it is bad. We have at least one brake line to replace this week so swapping in a new one won't be too big a hassle assuming we can find one.

I also found this:



That is not somewhere that should have power. We'll get into it tomorrow but I'm thinking this has something to do with it.



It delivers power up into the dash.

Final question for today:



I assume that the lower hose connection there on the heater box that missing a hose and open is the coolant return but I can't figure out where it should connect back to the engine or radiator. Where should it hook up?

[RiverPatrol]

I have a few more questions that I couldn't figure out from looking at the truck and the diagram.

I assume, having looked everywhere else I can think and not finding anything else that could be it that this is the brake light switch.


Looking at the diagram it should be normally open and then close when brake pressure is applied. In testing it is open all the time reguardless of pressure in the system. I'll recheck it in the morning but I'm thinking it is bad. We have at least one brake line to replace this week so swapping in a new one won't be too big a hassle assuming we can find one.

Yes, that's the brake light switch. There should only be 2 wires going to it, both green. It looks like there are 3

I also found this:



That is not somewhere that should have power. We'll get into it tomorrow but I'm thinking this has something to do with it.



It delivers power up into the dash.

That's all for that aftermarket A/C.

Final question for today:



I assume that the lower hose connection there on the heater box that missing a hose and open is the coolant return but I can't figure out where it should connect back to the engine or radiator. Where should it hook up?

That heater hose should connect to a 'T' fitting on the lower radiator hose.

[moore_rb]

That alternator is "cheater" wired.

The green wire that goes to the dash is for (or should be for) the alternator charge indicator lamp. The white/red stripe wire is the Patrol's original charge output wire, and should go to the top of the fuse block (which it seems like it does from the pics you posted), and the second small green wire that is jumpered to the output post is the load-sensing wire, and should actually be run to the load side of the fuse of a high-draw component (like headlights)

The way it's wired will work, but it's not ideal.

regarding the 12v lead on the load side of that one fuse - that's bizarre.

[Esteban]

In addition to Robert's comments, I would suspect that the alternator could be the culprit in the parasitic drains that you're having. Maybe even with the voltage reading at the fuse box.

Why don't you disconnect all the wires at the alternator and take some readings again?

[Cameron110]

Rob thanks so much for the insights about the alternator I was just looking at that mess and trying to figure out WTF was going on there. the green wire that runs up into the dash, it is bodged in on the ignition so it is sensing a load but we'll move it somewhere more sensible.



Things in the dash are about as bad as I was expecting, pretty hacked up but not irrevocably so.

Wire nuts are SAE approved right?



a few more shots



at least when they cut the tape away here they made sure to put a good gash in one of the wires. If you are gonna bypass all the fuses you want to be sure to create a fusible link by letting in some green death.

[RiverPatrol]

That alternator is "cheater" wired.

The green wire that goes to the dash is for (or should be for) the alternator charge indicator lamp. The white/red stripe wire is the Patrol's original charge output wire, and should go to the top of the fuse block (which it seems like it does from the pics you posted), and the second small green wire that is jumpered to the output post is the load-sensing wire, and should actually be run to the load side of the fuse of a high-draw component (like headlights)

The way it's wired will work, but it's not ideal.

regarding the 12v lead on the load side of that one fuse - that's bizarre.

The '67 Patrol would originally have had a generator in it. To accommodate the higher amperage needed by the A/C, they installed an alternator. That requires a little bit of rewiring, as you have pointed out before.

[Marshall]

We spent some more time chasing the charging system and other issues today. The strange thing is that the alternator as it was wired was putting out 15-16 volts at normal operating RPMs, that is enough to be bad for all kinds of things. The long green lead that Rob said should go to a charging light was spliced in to the coil power and both were spliced to the yellow with blue wire that enters the harness with the wires for the ignition switch and the start button. We played around with various configurations and when the "cheater jumper" is removed the alternator puts out a much more reasonable ~14 volts. The question we have now about the alternator is how we can tell which connection should be for the charging light and which should be the load sensing lead? We haven't found any markings anywhere and given the ridiculousness of the other wiring we're hesitant to assume that it was correct.


It seems that the ignition switch has been swapped at some point rather than being off-acc-run with a separate start button the one in there now is off-run&acc-start(momentary). There were some very strange jumper wires between the start button the ignition switch and the AC compressor switch which we cleaned up.

[Esteban]

Robert wrote an excellent topic regarding installing a GM alternator (Delco) that's a must read.

How-To: Wiring a GM 3-Wire Alternator into your Patrol

http://www.60patrol.com/forum/viewtopic ... 46&p=29297

[RiverPatrol]

The original ignition switch only had an off and run position. Then there was a starter button above it. There was never an accessory position on a Patrol switch.