350 Chevy Small block starting problems ***please help!****

[systmofadown22]

Re: 350 Chevy Small block starting problems ***please help!****

the reason it tries to fire as you are releasing the key is there was 2 circuits. one for 12 volts while cranking and one for 9 volts while running. Now you need 12 volts for both, and you have none foe cranking. recheck the wiring. There needs to be 12 volts to the coil from the ign. side of the key. you can get this from the starter sol. if i remember right the term closest to the motor is the run side. anyway one will have an "S" and the other will have an "R" marked on it. you want the "R" side. make a new wire from there to the coil, as the old one is a resistor wire. just a 10 or 12 gauge should do. prefer 10. If it has a ballist resistor, bypass it. and your good.

Ok i'll give it a shot. So when I run the wire from the "R" side, I connect it to the positive side of the solenoid?

 

[systmofadown22]

Re: 350 Chevy Small block starting problems ***please help!****

the reason it tries to fire as you are releasing the key is there was 2 circuits. one for 12 volts while cranking and one for 9 volts while running. Now you need 12 volts for both, and you have none foe cranking. recheck the wiring. There needs to be 12 volts to the coil from the ign. side of the key. you can get this from the starter sol. if i remember right the term closest to the motor is the run side. anyway one will have an "S" and the other will have an "R" marked on it. you want the "R" side. make a new wire from there to the coil, as the old one is a resistor wire. just a 10 or 12 gauge should do. prefer 10. If it has a ballist resistor, bypass it. and your good.

Ok I just tried this. I have a starter which enters in the port side of the engine. The positive battery cable screws into the back of it, with a yellow wire screwing into the "S" side of the solenoid. I ran a wire from the "R" side of the solenoid (nothing was screwed in there previously) to the + side of the coil. I tried cranking the engine with the ballist resistor connected and once with it not connected. Still the same result. Cranking over, won't fire.

 

[myoldboat2]

Re: 350 Chevy Small block starting problems ***please help!****

yeah, ignition system problems are frustrating.

my mercruiser 140 had one of those resister wires in the wiring harness. they get old and deteriorate. then when they warm up after running, their resistance increases too much, and the starting voltage drops. i have a pertronix ignition like you. they are digital in nature--if the starting voltage drops below some level (like 7 to 9v or something), the pertronix shuts down. it took me a LONG time to figure out what was happening. i ended up bypassing the resister wire. first i added an external resister and put in the coil for that--no joy. i ended up removing the external resister and running a coil with internal resistance. not what was called out but it has worked great for many years now.

are you sure your pertronix is still good? you can't leave the key in the "on" position for too long without the engine running, because it will ruin the pertronix. the "aux" position is ok.

 

[systmofadown22]

Re: 350 Chevy Small block starting problems ***please help!****

yeah, ignition system problems are frustrating.

my mercruiser 140 had one of those resister wires in the wiring harness. they get old and deteriorate. then when they warm up after running, their resistance increases too much, and the starting voltage drops. i have a pertronix ignition like you. they are digital in nature--if the starting voltage drops below some level (like 7 to 9v or something), the pertronix shuts down. it took me a LONG time to figure out what was happening. i ended up bypassing the resister wire. first i added an external resister and put in the coil for that--no joy. i ended up removing the external resister and running a coil with internal resistance. not what was called out but it has worked great for many years now.

are you sure your pertronix is still good? you can't leave the key in the "on" position for too long without the engine running, because it will ruin the pertronix. the "aux" position is ok.

Yeah the pertronix is still good. I just put it in about a week ago, and I never leave the ignition on when firing it up. When the boat died on me initially, I checked the points, and it was equipped with dual points. One side was sparking, the other was not. That was when I decided to switch it over to a electronic ignitor....HOPING that would fix the issue. Nope still no luck. It just puzzles me as how it ran fine, fired right up, put it in the water, drove it around for 20 min, and then it crapped out. Now it wont start. I thought it was the fuel, but it's going in to the carb with no problem. It's gotta be a spark issue.

 

[chunckj]

Re: 350 Chevy Small block starting problems ***please help!****

I will try as best I remember to give you a flow chart for ignition. all voltage checks should be made with a test light hoked up while checking voltage with a volt meter, this way it puts a small load on the circuit and checks that you have current as well as voltage. If the voltage drops when a test light is connected it means you have a bad conection somewhere. Check for B+ at the coil+ both key on and engine cranking. If you can do a voltage drop test, do one between the battery+ and coil+ and between the battery- and engine block. If every thing is ok less than about .2 volts hook a test light between B+ and the coil- crank the engine if the test light blinks your points/pertronix is ok if not you need to check that it is hooked up properly. It may also be a bad ground from the distributor to block or block to battery. If you know the specs on the coil you can check the resistance between the primary and secondary side of the coil. the resistance between coil+ and coil- should be around 3-4 ohm and the secondary coil+ and the coil tower (where the wire goes from the coil to cap) it depends on the coil but it should be over 1,000 ohm. but not open. Another explination for what your describing is a bad ground between the engine and the battery. do a voltage test between the engine block and battery- while cranking the engine if there is more than .5 volts you need to add a ground or replace the ground wire. This would also explain the voltage gauge problem, and no spark. The engine may have been grounding through a control cable.

 

[chunckj]

Re: 350 Chevy Small block starting problems ***please help!****

Have you had any luck?