can't get Josephine to start

[Kohrn Sirrup]

Hello again folks. I finally got my brake issue resolved,I don't ever want to go through that again! Now after 3 weeks of brake work I go to start her up and nothing! WTF?? I replaced the battery,starter,solenoid, wires ,everything. It will start with a boost from my truck but not on her own. I've trouble shot the solenoid, it seems fine. It's new. I'm at wits end,again! Any other ideas ? Its a 54 Flxible with a 72 GMC 401gas engine,5 speed trans. Thanks again!

[sparkplug188]

Try to find a loose connection somewhere by testing for voltage drop with the start circuit under load (while trying to start the engine).  Here is a video of how to do a voltage drop test. http://youtu.be/ry68G0C2Fyc  You will probably find 3-4 volts not making it to the starter because of a bad connection.

Edit: Another thought-- Could there be a small electrical load somewhere that is draining your new battery?  What is the battery voltage at when it won't start without the truck or charger?

[eagle19952]

additionally....what is the voltage at the battery....
what is the voltage at the battery when cranking...
what is the voltage at the starter when cranking....

[Jim Eh.]

Grab your battery terminals and give them a good twist. If there is any movement they are simply not tight enough.

[Kohrn Sirrup]

Thanks guys. I'll try a voltage test. I have to buy a voltage meter first. I've tried chasing down a short but not having much luck. I've cleaned off all the contacts I can find.Traced back all the wires from the switch but i dont see anything grounding. Thanks for the ideas..

[mung]

"Grab your battery terminals and give them a good twist. If there is any movement they are simply not tight enough."

One at a time please, or you might be the one that won't start.

[MightyThor]

Does it turn over strong on the boost, but weak on your battery?  Or, not turn over on the battery at all?.  GM starters are notorious for not giving full voltage thru the solenoid if the juice to the solenoid is not strong.  So even if you have 12 volts in your main battery cable, the solenoid may only make partial contact if it is getting say 10 volts to the wire that triggers the solenoid.  This is because the GM has to have voltage that pulls the solenoid plunger in, against spring pressure moving both the gear on the starter nose, and moving the disk that passes electricity through the solenoid to the starter.  If there is not enough juice to make a strong magnetic pull, the disk may only make partial contact and the result is resistance through the solenoid and reduced voltage to the starter motor.  

One way to test this condition is to jump the starter.  By this I mean you connect between the big hot wire on your solenoid directly to the stud where your trigger wire is attached.  If the starter turns good this way, chances are you are not getting enough voltage to the solenoid thru the wire from the starter switch.  If it does not spin good with this test, could be bad main battery cable, bad battery, bad solenoid, bad starter or combination of all.

[Kohrn Sirrup]

I've tried jumping the solenoid and it spins fine when I do. The solenoid is new,or at least I think it is. It came with the bus and it looks brand new. It spins just fine when I jump it with my truck,fires right up. I have another starter and solenoid I could try. Maybe I should get a new one. Thanks for the reply.

[eagle19952]

when you jump from your truck ... where are you hooking the cables ?

[digesterman]

I'll try a voltage test. I have to buy a voltage meter first.

Kohrn having a electrical meter is really essential. If you don't want to spend the bucks on a fluke right now get yourself a meter at home depot, they have some relatively cheap ones, 60 - 70 $, that will even give you AC amps. I have several laying around because everytime I try to find one of my good ones I can't, either someone has borrowed it and not put it back where it belongs or I laid it down in the middle of a project and forgot. At any rate trying to troubleshoot without a meter is very difficult. Sounds like you have some connection problems, good luck.