starter jumps?

[fatboy]

Still having starting problems,

when I turn the key to start engine turns over fine but does not start, I let off the key and in falls to the run position and the eng starter disengages like it should but here is the problem when I go to turn the key to off the engine jumps like it wants to start and the carb spits fuel out of it. It is getting stray voltage from somewhere but where.

85 chevy suburban with unilite distributor, jacobs coil msd 6a ingnition box new start switch, fuses are all good, optima battery but will be dead out of the blue.
held multimeter on battery and wiggled wires pulled fuses and messed with everything I could think of but no change in voltage.

should the positive wire going to the altinator be hot at all times? with key in or not. the voltage draw wire going to the voltage regulator not to the battery.

when it does start timing is correct it will run fine for days and then one day it will give me hell.

 

[fatboy]

no one ever had this problem? I am stumped!!!!

 

[OrangeCrushK10]

I have a similar problem with my truck.

When I put the key to the start position the starter cranks the engine over like it's supposed to, but the engine will not start. When you let off and the ignition turns back to the run position the engine will start up. It's a real pain in the a$$, I tell ya.

I think it does this because the last owner jacked all the wiring up when he installed the 350sbc. I've replaced the starter and it didn't look like there were any loose wires, so I think it's just completely missing the wire.

Maybe someday I'll buy one of those painless wiring kits for my truck and re-do the wiring. Sorry I can't help, but you're not alone with odd ignition wiring.

 

[pauly383]

Could just be compression perhaps ? When mine wouldn't start , it would do that as you release the key . I got pissed at my truck and smacked the distributor cap and it fired right up , replaced my coil and module with trail spares and no problem

 

[fatboy]

Thanks for the input. I checked the coil and it was not within the specs so I replaced it and it seems to run better but I still think there is a short somewhere

 

[goldwing2000]

More than likely, the problem is where you are feeding the ignition from. There are two different ways of getting key-on power. You have constant key-on power (as in for the ignition) and you have normal key-on power (like for the guages, radio, etc.) that shuts off when you are cranking the engine.

Make sure that you have your new ignition wired to the original ignition circuit and everything should be fine.

Other than that, you might have a dodgy ground somewhere that's losing connection with the higher draw of the starter motor.