Gremlins in the electrical system, 86' Suburban

[odiez1]

Folks, I'm at my wits end. My 86' 6.2L Suburban is driving me crazy.
This might be my first posting with a serious mystery.

I'll start by listing what has stopped working. Maybe there is a failure common to all these, but I've had no luck finding a complete wiring schematic to follow.
-Dash instruments are all dead. Water temp, oil pressure, fuel level, battery volts. All instruments.
-The key-on 20 second chime has stopped.
-Power windows
-Radio
-AC/Heater blower fan.

BUT, the glow plug controller is working. The engine starts and the batteries are charging! Power door locks work, and all the lights inside and out.

When I pull the light switch ON, it chimes like the engine is NOT running. [continuously argh.. ]

I replaced the ignition switch on the upper side of the steering column, behind the dash, then the windows, blower fan, and radio stopped working. But I did that because of the other issues.

Could someone please help me here? Thanks so, soooo much!

-Aaron

[legendman]

There are some fusible links down by the starter that feed power to cluster and accessories

[heymccall]

4 inches from the starter hot post are several plastic encapsulated butt connectors, to attach the fusible links to the primary wires. The connectors have corroded. Cut/ crush the plastic off, cut the connector out, and crimp new ones on.

Battery hot goes to the starter big stud, and that same BIG stud had several smaller wires that leave and go over the bell housing. Those wires feed the key switch and fuse panel. Those crimps are, most likely, the problem.

[odiez1]

I'm totally going to check that as soon as I get home.
Thanks a lot.
I just replaced the starter, so that may be related..

- Aaron

[heymccall]

If the problem started the moment you finished installing the starter (which you forgot to mention), then either the stud nut is loose, or, you didn't attach all the eyelets.

While we're at it, I see tons of threads with broken engine blocks because the starter support bracket was not installed. It needs to be there.

[odiez1]

Yes, the support bracket is connected. it wasn't when I purchased it. the bolts had been drilled/ tapped to 1/2 inch. I successfully helicoiled the outer one. and they are ok now.
the old starter was tested and bad...

as difficult as it may be getting it connected right, it's important to do. really, once the larger bolts were right the bracket lined right up.

- Aaron

[odiez1]

Originally Posted by heymccall

If the problem started the moment you finished installing the starter (which you forgot to mention), then either the stud nut is loose, or, you didn't attach all the eyelets.

While we're at it, I see tons of threads with broken engine blocks because the starter support bracket was not installed. It needs to be there.

Hey again.
I just got out from under the starter, and apparently the bolt from the bracket to the block has backed out some, but still hanging on.. I think it's just the bolt is damaged more than the block I hope.
the wiring tho seems ok. the inline fused links were in tact, but oily and fuel covered. I found the fuel filter leaking.. a good jiggling on the wires didn't produce results.

This didn't start right after replacing the starter, about 3 weeks later.
I'm going to pull the starter for a closer inspection, and replace that blot.

Thanks again.

[roadhog0]

If it's like my truck the cab power comes from the back of the alternator. Check that fusible link. But that's almost what I would bet it is. Had more than one of those piss me off and make it so a rig wont work right.

[zaccaglin]

Originally Posted by roadhog0

If it's like my truck the cab power comes from the back of the alternator. Check that fusible link. But that's almost what I would bet it is. Had more than one of those piss me off and make it so a rig wont work right.

My 85 burb is the same as this above. I was replacing my fuel pump and had my alternator out. Went to call it a night and lock up the truck and was curious as to why my key-less entry remote wasn't working. After cursing it all night, checking fuses, and looking for the non existent fusible links on my starter i gave up. Next day went ot put it all back together and as soon as i put all the wires on the Alt. bolt i heard my Radar detector kick on. Never felt like such a dummy in my life..

Anyways rant over, check behind your Alt. as well lol.

[odiez1]

Ah the alternator! That is next.
I just finished testing the starter area. I've got 12v from the battery to the main post, through the smaller red wire past the 14A inline link. The other smaller post has continuity to ground with the key off.

It's strange that the Suburbans wiring is different from the Chilton book I have, or is it?..

Now I've checked the alternator also, and found a black wire off. I'm not sure if I jiggled it off, or if it was already off because it didn't seem to have an effect, but I haven't started it yet.
There's 12v across both sides of the 12A inline link at the Alt, and now I have pictures of the areas.
1) The Starter has 2 wires from the Battery post, a single black wire for the solenoid, that seems different..
2) There's 2 wires off the main Battery connection, the smaller black goes to the Alt.
3) pic is upside down.. besides some crud, all the other wires at the Alt were connected, except the black on on the left side. It may have come off when I was testing them tho.

Also, there was 12v on all the wires from the Alt bolt, even tho it's covered in crud..
I'm using a needle to stick the wires for the volt meter test.

I'm going to get a replacement bracket bolt now..

You guys ROCK!