important GMC - its broke - HELP

[Guest catweazle (Banned Member)]

[Tony B]

I keep telling you!! I tried sanity once, didn't like it at ALL! Mind you I did make the mistake off looking at Catweazel's post, just before I WAS going to eat. Can't he done for cruel an inhumane behaviour exposing that to us? Off to Chatham Vetran's Day tommorow with the 101.

[R Cubed]

Tony,

 

You keep on about solenoids, but I am sure GMC's do not have them, it is like a Jeep, and many other vehicles of the era, just a main starter switch direct from battery. No wonder Jack is getting confused.

 

As for the rubber hammer, you might feel better after using it, but very doubtful of it curing anything :???

 

Quite right, the GMC starter has a mechanical foot pedal which engages the starter gear to the flywheel and then connects two big copper contacts together to energise the starter motor. This sits directly on top of the starter motor so the only connection you can see is the one connection that the battery cable goes on, the other connection is internal to the contact box on the top of the starter.

[Tony B]

Same as the Dodge then. In that case, has the push rod worn through the bulkhead? Not engaging fully. If as Jack says all the power is where it should be, then the switch or starter must be suspect. The battery blowing out in a few months is a worrying thing though. (I still reckon the rubber hammer though, you don't nessacarilly have to hit the starter)

[Stormin]

What insulates the contacts on the starter pedal mechanism from the rest of the engine and frame?

My money is on one of these insulators breaking down due to wear and tear and causing a partial short and current drain.

 

Norman

[DocCBritt]

Have you tried pulling the starter? I'd pull the starter motor and give it a bench test..... Sounds like it tried to crank, and something shorted and it died. This giving you a constant draw/short and no voltage. If that tests ok then I would check the starter switch.

A faulty harness you have given you problems before hand, like a no crank once and awhile, (like when very humid) and needing a jump to start..... I had a situation like this with my Kenworth..... My two cents....

 

And if worse come to worse there is always the hand cranks start method. (hope you dont have a winch)

[Jack]

Thanks chaps.....:sweat:

 

Ok to recap.

 

1. I have power in the battery - albeit 10 volts...

2. there is to the starter

3. no power is going through the loom or anywhere else - even if the battery was completely stuffed there would be enough power for the indicators to work etc etc........but I have none.

 

Gonna call Ghost Busters in the minute.:cry:

[DocCBritt]

Jack,

 

I had a problem kind like this with one of my Kenworths awhile back. Like I had stated I would have "issues" with cranking on wet or humid days. If I slaved or jumped the truck it would start and be fine afterwords.... But I was 24 volts at the batteries.

Finially came a day where she had nothing, low power to accessories but no crank.

I started at the batteries. All showing 13.2 volts checked all the battery cables and replaced all the had corrosion in the wire itself under the coating. Nothing.... I then started tracing the main harness from the battery box unbolting the harness and pulling it from the casing. (a 264" wheelbase semi tractor) Finially I found the spot, in a place where the case and the protective coating had split under the 66" sleeper and all the roadsalt from winter roads had found its way into the wire... A 5/8 inch power wire was totally green from corrosion and under the green all the wires were broken except 1 strand in the middle, still connected. So all the corrsion was a huge resistor and finially when there way only 1 strand intact there was not enough surface area on that strand to push enough voltage thru to crank that 575HP caterpillar diesel.

This is more than likely your problem, start tracing your main harness..... This will suck but once you find it you can butt connect repair the bad area. Make sure you soldier all the connections and shrink wrap the repaired area and the brush on more paint on wire coating over the shrink wrapped area to keep mother nature out.

Good Luck.

[Tony B]

OK no power anywhere other then at the starter. That is odd. The fact you have power at the starter but no turning the whole thing is looking like an earth problem. Your head and side lights should operate independently of ignition switch. First of all check earth, again, make sure it is clean, take it off rub back to bare shiny metal, make sure earth lead from is clean at both ends, restraing bolt and nut are clean and bright replacing it would not be a bad idea. The earth can be sealed with nail varnish. That ensures one end of the problem is solved. After that if no joy work up from power side of battery. There has to be a place were the lead from the battery joins a junction box to distribute the power round the seperate cicuits. Replace that wire, make sure you use a thick cable such as 1.5 mm. reason for that is it the cable that has to carry most power (electrickery runs on the SURFACE of a wire, that is why a thin multistrand can carry more power than a single thick wire). From there you can try disconnecting each circuit and see if the problem dissapperas. If that happens you know which circuit is causing problems. Then start tracing up each circuit. Long and tedious but no ther way. The 'good' point is it ALL dead, so the problem will probably be were all the bits meet, which is basically junction box on the 'Outward journey' and Earth on the back bit. Does your meter have a continuity tester? that would make life a little easier.

[Guest catweazle (Banned Member)]

Thanks chaps.....:sweat:

 

Ok to recap.

 

1. I have power in the battery - albeit 10 volts...

2. there is to the starter

3. no power is going through the loom or anywhere else - even if the battery was completely stuffed there would be enough power for the indicators to work etc etc........but I have none.

 

Gonna call Ghost Busters in the minute.:cry:

For goodness sake jack get one of TBs diplomas to frighten it back to life:rofl::rofl::rofl:

[Degsy]

For goodness sake jack get one of TBs diplomas to frighten it back to life:rofl::rofl::rofl:

 

 

Got any particular one in mind CW?:???

[Chrisg]

For goodness sake jack get one of TBs diplomas to frighten it back to life:rofl::rofl::rofl:

 

 

Wots TB?

[Guest catweazle (Banned Member)]

Wots TB?

Its tuburculosis.a desease which creaps up on you,then its to late.

Please note no spell checkers are harmed in any of these posts.

[Tony B]

if you want to TB you can always Badger it! :cool2:

[TooTallMike]

Got any particular one in mind CW?:???

I got it as well :rofl:

[LeeEnfield]

if you want to TB you can always Badger it! :cool2:

 

 

 

 

Can you............:undecided:

[abn deuce]

With all the Mechanics attending the W&P show did anyone finally come up with a fix for Poor Jacks ailing CCKW ???? Or will it now be broken apart for spares for other CCKW's ???

[Jack]

I am 'going in' this weekend ABN..........

 

My landlord came in this week and said "I know it is a work of art and I know you love it Jack - but could you move the f*^%£$g thing" he did say it in a very nice 'officers' class sort of way............!

[Richard Farrant]

 

I know you love it Jack - but could you move the f*^%£$g thing

 

:-D:-D:-D:-D:-D:-D:-D:-D

 

Stand by all Mechanics.............inbound technical queries likely from our award winning leader :shake:

[Degsy]

:-D:-D:-D:-D:-D:-D:-D

 

Stand by all Mechanics.............inbound technical queries likely from our award winning leader :shake:

 

And the answer won't have changed.....START WITH THE BASICS:argh::sweat:

[abn deuce]

Is there no ONE who can pop over to Jack's and get his CCKW back on its feet !!! surely with the prospects of Tea and cookies , not to forget a chance to view the Very prestigious award Plank ....if Jack were to let the first successful Mechanic touch or hold the award who will be the first to give it a try ??

[Jack]

Is there no ONE who can pop over to Jack's and get his CCKW back on its feet !!! surely with the prospects of Tea and cookies , not to forget a chance to view the Very prestigious award Plank ....if Jack were to let the first successful Mechanic touch or hold the award who will be the first to give it a try ??

 

ABN has a damn good point..........!

[Joris]

It's still broken?

[Richard Farrant]

Is there no ONE who can pop over to Jack's

 

 

POP OVER ?????? :??? ...... Dorset is at the outer edge of the Universe :-D

[snowtracdave]

It does to us but for a gentleman in The Colonies it's just down the road,comparitively speaking.:-D