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

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Hello....I have a frustrating issue. Just bought a 91 commander jet boat with a 350 chevy small block. I replaced the battery, battery cables, starter and the spark plugs. It started up just fine, ran it on the lake for about 20 min then all of a sudden the engine died. I started it back up and the engine sputtered, then died again. I eventually got back to shore and now the engine doesn't even start up. It cranks, but won't fire. It has gas in it, fuel is being squirted into the carb so there is no issue there. Spark plugs are fine. I even replaced the starter key ignition switch. One problem I was able to find was I had a dual point ignitor, but one side would only spark. I replaced it with a Pertronix electronic ignitor, thinking it would be the issue. Now when I crank the engine, it will turn over, but as I let go of the key, it tries to fire. I did the spark test, and as I'm cranking the engine there is no power going from the coil to the distributor, but as I let go of the key, there is a spark from the coil to the distributor. I even replaced the coil also. Tried using Engine Start with Ether.....still not firing up. Do you guys have any suggestions? LOL...I'm ready to take it to a shop.
 

searay3

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

Lose the ether or lose your motor. You don't need it. Check for 12v at the +side of the coil, key on engine off. If you do, recheck the instructions on how you wired everything. Could be you have something wrong in your installation of the new distrib.
 
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Re: 350 Chevy Small block starting problems ***please help!****

Lose the ether or lose your motor. You don't need it. Check for 12v at the +side of the coil, key on engine off. If you do, recheck the instructions on how you wired everything. Could be you have something wrong in your installation of the new distrib.

Thanks for your reply. But it was doing this before I put the new ignitor in. I ony replaced it after it had died on the lake. I'll give it a shot though.
 

chunckj

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

I have seen this before, A wire cold have been geting a cross feed 12V during cranking and now it isn't. Automotive startors have a terminal on the startor to give a full 12V while cranking and bypass a resitor. An easy check is to hook a jumper wire from known 12V to the coil and see if it starts, just know you will have to pull the wire off to stop the engine. If this gets it see if the startor has an R and an S terminal , I belive you would want to run a wire from the R to the B+ on the coil. If you really want to do it right put a diode in line to prevent back feed. Good luck
 
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Re: 350 Chevy Small block starting problems ***please help!****

I just checked and only 2.85 volts was coming out. Any ideas what the issue could be now? I'm wondering if the ballast resistor is causing this problem because I put in the pertronix electronic ignitor....or I just wired it wrong....
 

chunckj

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

As long as your coil can take a full 12 volts get rid of the resistor, it's only there to protect the points. Just make sure it's 12V while cranking.
 

searay3

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

Pay close attention to your wiring instructions and make sure the 12 volt source you are using is switched at the ignition. Don't know what power package you have as lots of the boats of this size use chebby's, so I can't help you with the coloring of the wires.
 

FreeBeeTony

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

If memory serves me correctly.........the ballast resistor is not needed with the Pertronix ignition.
 
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Re: 350 Chevy Small block starting problems ***please help!****

If memory serves me correctly.........the ballast resistor is not needed with the Pertronix ignition.

I just unplugged the wire from the ballast resistor to the + side of the coil. When I turned on the ignition, it shot up to 12V which was good. The engine cranked, but still wouldnt fire.

I'm just so thrown back as to why it ran for 20 min perfect, died on the lake, started back up, died again. When I got home, it wouldn't start up at all. Checked the dual points and only one was sparking. Took that out and replaced it with an electronic ignitor. Still doing the same thing.....not firing up.
 

snoski

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

Did you possibly kill the coil????
 

Bondo

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

When I turned on the ignition, it shot up to 12V which was good. The engine cranked, but still wouldnt fire.

Ayuh,... Is there 12Vs at the (+) terminal of the coil,.. While it's Cranking over,..??
There should be a wire from the starter that supplies the coil,.. While Cranking on the starter,.....
It's the small terminal on the solenoid, away from the block...
 
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Re: 350 Chevy Small block starting problems ***please help!****

Did you possibly kill the coil????

No...it did this when I had the old one, and I replaced it thinking that could have been the issue. But no....still not starting up.
 
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Re: 350 Chevy Small block starting problems ***please help!****

Ayuh,... Is there 12Vs at the (+) terminal of the coil,.. While it's Cranking over,..??
There should be a wire from the starter that supplies the coil,.. While Cranking on the starter,.....
It's the small terminal on the solenoid, away from the block...

Here's what happend. The voltmeter guage on the boat would read about 8-10volts when I turned the key without cranking the engine. I unplugged the wire going from the ballast resistor to the + side of the coil. Now it's reading 12V when I turn the key on. I used my volt reader to see how much was being put out at the + end of the coil while being cranked and it was only showing 2.85 with the ballast resistor plugged in. This morning I unplugged the wire going from the ballast to the + end of the coil. Didn't check what the reading was with my volt reader, but it still didn't fire up. It's doing this thing where the engine will turn over, but after I let go of the key, it sounds like it's trying to fire but doesn't. Like it's firing at the end and not at the beginning.
 

Bondo

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

Here's what happend. The voltmeter guage on the boat would read about 8-10volts when I turned the key without cranking the engine. I unplugged the wire going from the ballast resistor to the + side of the coil. Now it's reading 12V when I turn the key on. I used my volt reader to see how much was being put out at the + end of the coil while being cranked and it was only showing 2.85 with the ballast resistor plugged in. This morning I unplugged the wire going from the ballast to the + end of the coil. Didn't check what the reading was with my volt reader, but it still didn't fire up. It's doing this thing where the engine will turn over, but after I let go of the key, it sounds like it's trying to fire but doesn't. Like it's firing at the end and not at the beginning.

Ayuh,..... Your Wiring is AFUp...

The only thing the resistor is supposed to be resisting is the Coil... You're showing it on the Voltmeter...
It's doing this thing where the engine will turn over, but after I let go of the key, it sounds like it's trying to fire but doesn't. Like it's firing at the end and not at the beginning.
The last line of my previous post deals with Just That....
 
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Re: 350 Chevy Small block starting problems ***please help!****

Ayuh,..... Your Wiring is AFUp...

The only thing the resistor is supposed to be resisting is the Coil... You're showing it on the Voltmeter...

The last line of my previous post deals with Just That....


Thanks. I really appreciate the information on this. So is there a way to fix this issue?
 

Bondo

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

So is there a way to fix this issue?

Ayuh,.... Sure,....
All it takes is a Test Light, Multimeter,+ an understanding of What goes Where...
With the vague discription of your driveline,... I don't know Where you'd find a diagram,...
Not that it matters,... Your's doesn't sound like it's even Close to Stock...
 

Maclin

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

Regarding ballast resistance or not, the coil determines that. There are external resistance coils and internal resistance coils. The type of ignition does not determine if the coil can "take" the full 12 volts or not. An electronic ignition system can be designed either way, for internal or external resistance coils. Be sure to replace it with whatever the circuit was designed for.

Ballast is the operative description of why the resistance component is in the circuit, it helps to maintain balance kind of like a wheel weight sorta. Coil circuits experience normal resistance as well as reluctance, which is resistance to the building of magnetic flux lines, kind of like a head wind. In this way the ballast is like the tail of a kite, when things get windy the ballast helps keep it from getting too far off kilter.
 
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Re: 350 Chevy Small block starting problems ***please help!****

Regarding ballast resistance or not, the coil determines that. There are external resistance coils and internal resistance coils. The type of ignition does not determine if the coil can "take" the full 12 volts or not. An electronic ignition system can be designed either way, for internal or external resistance coils. Be sure to replace it with whatever the circuit was designed for.

Ballast is the operative description of why the resistance component is in the circuit, it helps to maintain balance kind of like a wheel weight sorta. Coil circuits experience normal resistance as well as reluctance, which is resistance to the building of magnetic flux lines, kind of like a head wind. In this way the ballast is like the tail of a kite, when things get windy the ballast helps keep it from getting too far off kilter.


My question is...would the stalling on the lake before putting in the new pertronix ignitor be due to this electrical issue?
 

chunckj

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

Good chance it meesed up something you know what you got now and you know what you need I would stop trying to figure out what happend and just consitrate on geting it right. All you need is a wire that has 12V while cranking. Not all wires with 12V have it while cranking. Run a wire from the R terminal on your startor or the only small terminal without a wire going to it and try again. The reason it sounds like it is trying to start when you stop cranking is that when you stop cranking the ignition get's 12V and trys to catch. Two people have sugested this just give it a try it will work.
 

Bifflefan

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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.
 
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