1970 Chevrolet C10 New Truck with Old Problems

[gordyzx9r]

Yeah...no.  My fiance is already referring to it as a dilapidated old farm truck.

[gordyzx9r]

So, I'm trying to take care of a few minor things with my new old 1970 C10 I picked up recently. 
 
 I'm finding a few odd things here and there that I'm not sure either:
 
 What is it?
 What's it do?
 Do I need it?
 What was supposed to go in that mounting bracket (that nothing is mounted to anymore)?
 
 I'd really like to gut anything and everything I can related to emissions controls.  I don't live in an area where I need it...and most of it is dry rotted, capped off, and lines just sitting there anyways not connected to anything.
 
 Is there a really good fuse box diagram somewhere?  I downloaded the Chevrolet Chassis Manual from this site, but that's not exactly crystal clear.
 
 The fuel gauge is not working.  I need to troubleshoot that.  What resources are there here to do that?  There is a wire running from the center of the top of the tank (which I assume is the sending unit) directly to the fuse box.  Is it supposed to be?  Just to see what would happen, I pulled the plug out of the fuse box and the gauge went past full.  I put it back in, and the gauge goes to empty.

[gordyzx9r]

More.

[gordyzx9r]

And more...

[gordyzx9r]

What I've learned so far from the Chevy truck forums:

 1:  Circuit breaker - Not original equipment. Someone added one to mine like that when they installed a electric brake controller
2:  Vacuum ports. Best guess is the carb is not OE and those may not be used in your application
 3:  valve covers.  If you have no grounds place one from the head[where you have a bolt hole on the end] or intake or even the block to the frame them one from the motor to the cab. You can't have too many ground straps, it just helps the wiring out so much.
4:  flux capacitor
5.  Pink is your ignition power.
6:  is the vacuum port for an auto transmission. You did the correct thing to cap it since you have a stick.
7:  Evaporative canister purge line.  Canister purge is not evil.  It is a passive system and would allow you to have a closed fuel system.  That makes it so less fuel evaporates, less fuel smell, etc.  I am a big proponent of converting to fuel injection and getting rid of as much as possible, but I always leave canister purge.
8:  fuel pump n tranny lines
9:  As mentioned, big cap HEI and rubber fuel hoses on the pressure side (rubber fuel line is a great way to burn it down to the ground).
9:  The distributor is not original to your truck as the HEI type did not come out until 75-76. It will work fine as it produced better, higher spark without using point and condenser. Just remember to gap your spark plugs to 45. The original ignition system with points the spark plug gap is .35  The dist is not really out of place it is a HEI unit used on everything GM AFTER say 74. But they are so good and efficient that tons of folks retro place them on their trucks.
10:  I'm pretty certain that is not correct. The brown wire needs to go to the instrument cluster.
11. No idea.
12. Needs the floor mounted gas pedal.  You should have two "ball studs" that are screwed into the floor that the gas pedal snaps on to.
13. Looks to be the resistance wire that use to go to the points distributor.  Or; it is the brake warning lamp wire.
 14:  blower motor power-hook it up.

[Steve Wood]

no bad advice there. 

[earlbrown]

screenshot5 is a power plug and noise transformer from an aftermarket radio.  Toss it in the scrap metal pile.

[daveismissing]

pic5 looks like a transformer and since there ain't no such thing as a DC transformer I would guess it was an inductor to control alternator whine in the power lead to a radio- aftermarket radio harness?

AND EARL BEATS ME BY A GOOD 6 HOURS CUZ I DIDN"T READ TO THE END OF THE TEST LIKE THE TEACHER SAID

[daveismissing]

12 - resistors for either blower motor or IGN ballast?

Agree on #1 and 14

[gordyzx9r]

12 - resistors for either blower motor or IGN ballast?

Agree on #1 and 14

No idea.  They're not actually attached to anything.

[Pyro6]

Gordy, I always liked the cargo toolbox but they've always been on the drivers side. Doesn't matter, your trucks cool and you put you're personal touches to it. You can have my left and right arm, my shop, and my GN, but you can't have my 72 GMC.

[gordyzx9r]

So, decided to replace the fuel filter and the old rubber fuel lines with new rubber fuel lines (temporarily until I can get some metal lines).  Emptied the contents of the old filter into a bowl to inspect it and wow!  Either CA gas has lots of sediment, someone put dirt in the tank, or the tank is rusting from the inside. 

Also, I need to find a car cover for this thing...but just for the cab.  I don't have room for it in the garage, but it's got a leak somewhere and water is coming in.  Need to replace seals, and plug some holes I'm finding that they put in for a variety of reasons.

[Steve Wood]

I would guess the tank is rotten...time to replace the tank with one set up for fuel injection and get prepared for fuel injection

Order a shop manual so you can sort out the wiring.  As you have figured out, the stock distributor/coil used a resistance wire to provide 9 volts when running and a bypass wire to provide 12 v during starting.  That was eliminated when the hei distributor was installed as it takes 12 volts all the time.

A CS 144 alternator off a 94-96 Impala, etc. will replace the voltage regulator and old alternator and give a lot more reliability plus the ability to run anything you hook up like sound system, electric fans, electric fuel pump, etc.

[gordyzx9r]

Order a shop manual so you can sort out the wiring. 

Found a PDF online...from 1970.  Not the best.