1962 C30 - electric issues?

[Jeepers Creepers]

Hello everyone,
I bought this 62 c30 on craigslist for $1400 not too long ago. It runs well, burns some oil but not tons of it, and has a good tranny. The fenders are rusted out and so are the floorboards, the wooden bed is a loss, and in hindsight I probably paid too much, but I gotta roll with it now right? I'm OK at mechanical things but I really don't know much about electronics. The guy who owned it before me switched out the generator for an alternator, and everything worked fine for about a week after I bought it. But now, if you use the turn signal, there's no telling which light will come on (one, both, or none) and the voltage guage is going crazy. It used to register 12-14 volts, but now it stays on 8 unless you hit the brakes (moves a little) or use the turn signal (sometimes it jumps wildly if you use the signal). Anybody got any ideas? Where should I start? Inside the column at the turn signal or at the rear lights?

[Jeepers Creepers]

Forgot to mention I've checked the alternator (good), battery (functioning but not new), and fuses (none blown, replaced anyway since I had some).

[T and S]

Maybe a flaky ground ??

[Jeepers Creepers]

That sounds like a good place to start. At the risk of sounding wholly ignorant, are there two grounds from the battery? One to the block and one to the sheet metal? I seem to remember hearing that somewhere.

[Jeepers Creepers]

About the grounds, bear with me here. I will freely admit that the vast majority of my electrical know-how involves cursing at wires and blindly hoping they do what they are supposed to. Are there grounds in the system that aren't coming directly off the battery? As in, are there different grounds for each component (say, the turn signal?) or are there just the grounds at the battery?

[T and S]

Back in the day the factory did not ground these trucks very good. Your ground from the battery should go to the engine, make sure the connection is clean. Their is also a small wire going to the rad. support (on my 66'). To get good grounding for the truck, add a ground strap from engine to body, and body to frame, also add one from bed to frame. Grounds straps can be made, or bought at auto parts store.
Not saying this is def. your problem, but it is something to check for a first step.

[markeb01]

You can't go wrong with adding grounds. These trucks were notoriously puny with grounds. If you look at the headlights, they have 14 gauge wire heading to the high beams only, 16 gauge for the low beams and 18 gauge for grounds. And the tail lights use sheet metal to ground the circuit.

I've always connected a negative battery cable to the engine and the frame, connect all your forward grounds to the battery cable on the frame, and run another 14 gauge wire to the rear for positive grounding back there. Also run another 14 gauge wire from the engine where the negative cable bolts up, to the drivers side of the steering column and ground all your dash stuff there. These changes eliminate any further ground problems.

[Jeepers Creepers]

Sounds like a fun weekend of running wires! As far as the headlights go, if I hit the dimmer switch, they just turn off, and the turn signal feels really sloppy in the column (as in, it doesn't just click into place when you use it). Thanks for the tips!

[cooperhw]

Is that for sure a C-30? Dual rear wheels? If so I gotta see some pics of the rear of it.
I am build a 68 1 ton dually short bed step side pickup (out of an old motor home) and thought I was the only one out there crazy enough.
Was this truck a cab and chassis originally, (barely fit your hand between the rear inboard tire and the frame) of a long flat bed truck. Can you tell?
I am really excited to see more pics.

[Jeepers Creepers]

That is a great question. Now that I've been doing some reading, I think it might be a C20 that someone put C30 parts/trim on. It has the 235 straight 6 and I'm not sure if that even came in a C30. I'm just hoping it was worth the $1400.

[cooperhw]

It doesn't sound like the difference in truck will hurt that value. Almost any complete truck is worth that IMO.

[padresag]

Originally Posted by cooperhw

Is that for sure a C-30? Dual rear wheels? If so I gotta see some pics of the rear of it.
I am build a 68 1 ton dually short bed step side pickup (out of an old motor home) and thought I was the only one out there crazy enough.
Was this truck a cab and chassis originally, (barely fit your hand between the rear inboard tire and the frame) of a long flat bed truck. Can you tell?
I am really excited to see more pics.

you could also get a 1 ton without dual wheels(in the 133" w/b configuration) , so that would change your spacing between the rear backing plates and frame. 1 tons also had a deeper frame
ron

[padresag]

Originally Posted by Jeepers Creepers

That is a great question. Now that I've been doing some reading, I think it might be a C20 that someone put C30 parts/trim on. It has the 235 straight 6 and I'm not sure if that even came in a C30. I'm just hoping it was worth the $1400.

show the vin # and someone will explain it to you as the vin # will give the model designation. how long is your stepside box or what is the w/base measurement?
ron

[padresag]

Originally Posted by Jeepers Creepers

Sounds like a fun weekend of running wires! As far as the headlights go, if I hit the dimmer switch, they just turn off, and the turn signal feels really sloppy in the column (as in, it doesn't just click into place when you use it). Thanks for the tips!

replace the dimmer switch and there is a plastic piece in your turn signal switch that needs replacing. there should be a small ground cable usually passenger side rear eng to firewall and run one from the body to the frame
ron

[Jeepers Creepers]

I was wondering about that dimmer switch. Could be the culprit. I did some research and it is the non-dually c30 (tagged in cab 10,000 pound gvw with the 133 wb). Thanks for the tip. Do you know where to find the plastic piece for the turn signal?

[bhc41051]

I believe the 3/4 ton trucks had coil springs in the rear and the 1 ton trucks had leaf springs.

[Jeepers Creepers]

Originally Posted by bhc41051

I believe the 3/4 ton trucks had coil springs in the rear and the 1 ton trucks had leaf springs.

Yep, it's got the leaf rear springs and the 10,000 pound rating. It's a real beast. Rustier than I'd like but I needed something cheap and running.

[Jeepers Creepers]

Originally Posted by padresag

replace the dimmer switch and there is a plastic piece in your turn signal switch that needs replacing. there should be a small ground cable usually passenger side rear eng to firewall and run one from the body to the frame
ron

Hello Ron, thanks for that tip! Do you know what that plastic piece is called and where to find it?

[padresag]

just look up at any of the places that sell parts for these truck and just look for 1960-62 turn signal switch. I could get you the page nbr. but you have to learn how to do that for yourself. there is a list of vendors up top. top banana is in your area i think and others on here claim that they are reputable.
ron

[Jeepers Creepers]

Originally Posted by padresag

just look up at any of the places that sell parts for these truck and just look for 1960-62 turn signal switch. I could get you the page nbr. but you have to learn how to do that for yourself. there is a list of vendors up top. top banana is in your area i think and others on here claim that they are reputable.
ron

Haha, I didn't know you were talking about the turn signal switch itself. I thought it was something more mysterious, a plastic spacer or something. I've already got a switch coming in the mail. Thanks again!

[OldGMJon]

Originally Posted by Jeepers Creepers

That is a great question. Now that I've been doing some reading, I think it might be a C20 that someone put C30 parts/trim on. It has the 235 straight 6 and I'm not sure if that even came in a C30. I'm just hoping it was worth the $1400.

my 64' C20 came with a 230 inline 6. C30s w/single rear wheels as opposed to duel wheels were also produced.

[Jeepers Creepers]

Originally Posted by OldGMJon

my 64' C20 came with a 230 inline 6. C30s w/single rear wheels as opposed to duel wheels were also produced.

I had originally thought that the C30s were all dually because I've seen so many of them but a little research confirmed it is in fact a C30.