In the past five weeks, I have been paying lots of attention to her:

rechecked timing and advance

Took her out on the river today and she ran great for about 90 minutes. While cruising back to the marina at about 30 mph, the engine just stopped - like the throttle had been completely cut and the ignition switch turned off.

Was thinking perhaps the fuel tank pickup tube had gotten clogged so, when I got home, I disconnected the fuel line from the tank and put it into a 5 gal. can of fuel and ran it on the hose. Ran fine once the fuel pump got fuel to the carb.

Reconnected the fuel line to the tank and it ran fine there, too, for about five minutes.

Am wondering if there's debris in the tank that got sucked up into the fuel tank pickup tube and fell out during the drive home. Or if the fuel filter cartridge got clogged somehow. Or if the anti-siphon valve malfunctioned. 

Any other ideas?

The boat is equipped with a Prestolite distributor and Pertronix electronic ignition conversion kit.

Thanks

Did you check for spark out on the river right after it quit or did you pump the throttle and see if the accelerator pump was squirting gas into the primary throats?

Don't know how long it was from when it quit till you ran it again on the hose buty ou could have an ignition system issue related to heat and after the component cools off again, you have spark again till it heats up again and quits. It could be the coil or the ignition module for example or a mismatched coil and module or an electrical connection that needs cleaning..

The Pertronix haters will now line up to tell you what they think 

I think I'd go for a ride with the temporary tank hooked up, the timing light in the boat so if it quits you can pretty much instantly check for spark and either rule out a spark issue or confirm one.

If it doesn't quit on the temporary tank during the ride, then you know where to look (somewhere upstream of the pump). Make sure the temporary tank is vented so the fuel pump doesn't suck a vacuum in the tank and quit pumping.

Make small circles not too far from the launch ramp to minimize any paddling that might be necessary, and go upstream 

I am currently fixing a boat with only 2-3 year old gas that plugged up the injectors.  I did see you installed mostly the entire new fuel system but I did not see Drained the old fuel on your list.  

Old fuel does usually show up slowly with a lot of sputtering, yours seemed to be an instant crash so maybe the fuel was not your issue.

I did not check for spark or pump the throttle. Took about 90 minutes to get home. The coil is new and correctly matched with the module, according to SKIDIM. But it could have failed. Will take a spare coil next time out.

Good idea to take a temporary tank out for the next ride.

How do you check for spark using the timing light?

Thanks

I did drain the old fuel about six weeks ago.

The fuel in the boat tank is fresh.

Thanks

Just hook it up like you normally would and squeeze the trigger, push the button or whatever you have to do on yours to make the light flash.

Don't need to aim it at anything, crank the engine over and see if the light is flashing while the trigger is depressed..

It won't be flashing fast since the engine isn't running but if it's flashing while you're cranking then you have spark

No flash means no spark

JQ

Wasn't on the list, but I did check it about six weeks ago and will check it again.

The coil is brand new, but could be defective.

Will test primary and secondary resistance, and begin carrying a spare.

Instructions for ground and voltage checks:


Did a ground check and it was perfect. Zero resistance.

 I'd look at this TRB diagram and verify that you have about 12 volts at the following places

I did the ground test described above and found zero net resistance. Isn't that indicating a good ground?

Yes

Ken,

Followed your advice and checked voltage to/from the locations you suggested.
Have approx. 12 volts going into and coming out of the ignition breaker, into and out of the ignition switch and to the ignition coil (after disconnecting the power supply to the coil).

Also, the EI is apparently a PCM conversion module, not Pertronix.

So I'm leaning towards a diagnosis of either overheated/faulty ignition coil or a faulty EI module.

What say you?

Thanks.

P.S. Your expertise on these boats is pretty impressive.

Just to make sure we know which one you have, since it gets confusing, here are a couple of pictures  

Can spot his own distributor photo..............good job 

The 91589 kit you mention is as good as any other Pertronix kit.

If you were to install the original cam for the points, you'd need kit number 91582 but there's no difference in performance.

You mentioned that you have the original points stuff, now Pete's gonna get all hot and bothered and say to put them back in. 

You could do that and see how it runs for troubleshooting purposes.

You have to be careful that the points cam doesn't get installed 180 degrees out if you were to reinstall it. There's a little clip under that felt pad in the center of the shaft that will drive you to drinking, swearing and throwing things all at the same time. You have to get the clip off to remove the reluctor wheel and put the points cam in it's place........and then you have to get it back on all without destroying or losing the clip.

Right now, I'm thinking the issue was caused by a defective coil which was recently purchased. But we will see.

Thanks again for all of your help on this.

Sounds like a reasonable plan 

Here's a quote from 10 days ago Pete

8122pbrainard wrote: I should have mentioned it days ago - put the point set back in.

Put down the bottle Buck 

You don't say whether you've adjusted the timing at all, but since the light doesn't light up, I doubt it.

Having installed "a few" Pertronix units, I've most always had to adjust the timing some on the Prestolite distributors.

If you make a mark down where the distributor seats on the block so you know it's original starting point, you will probably have to rotate the distributor a little at a time and see if it starts and runs any better.

I'd start by advancing it a little (turning housing clockwise).

Keep in mind that if you move the distributor 10 degrees, that gives you 20 degrees of engine timing advance, so small adjustments are better than big ones

If no luck, go back to the original marks you made and go counter clockwise.

If nothing works you at least have the marks you made to get back to the original distributor location and put the Prestolite module back in.and recheck your timing.

Since the coil makes the spark and the spark is weak, maybe the coil isn't any good even though it's new. The module just tells the coil when to make the sparks

I'd probably put the Pertronix module back in and use the old coil and see what your results are spark wise.

That should tell you some good info.

I don't think I'd use the Pertronix coil with the Prestolite module though if it's the 0.6 ohm coil. It wouldn't play well with the Prestolite module.

It might be a silly question but are the positive and negative terminals on the new coil connected right.

If the wires were hooked up backwards the coil will still make some spark but not nearly the same intensity.

I will follow your advice and try the Pertronix module with the old coil after the weather here clears in a few days.

Am fairly certain the module was connected to the coil correctly, *but* it is possible that I made a mistake. Would be great if that's the case and all goes well when it is tested again.

I'd probably take them up on the offer. You'll have a new distributor with no wear on it.

Jonny Quest will say it just has to be RED 

Don't sweat it..................Buck got the bad coil or ignitor or whatever 

Oh, it will definitely be RED!

Your choice of colors of course. 

Since quite a few people have done this swap, one of them should be able to tell you what wires fit. I made some from a universal kit so the wires would be plenty long.

I *think* I can adapt/convert the distributor ends of the wires with a boot and terminal kit for about $10.

Also, Performance Distributors recommends using a new hot wire connected to the distributor from the starter solenoid or a fuse in most applications.

Finally, Summit Racing's website indicates the RED distributor won't ship for another month, but that's OK. They are great to do business with and I want them to make some money on this.

Thanks once more for your help.

Well at least you had good results based on your alternator/no spark thread 

Is the coil you have exterally ballasted? If so, did you connect the coil to the low voltage side of the resistor? 

Yes, and it is connected to the ballast resistor with a purple wire.

Did you leave the ignition key in the on position without the engine running? 

No, I did not and never have.

Can you quantify really really hot?

It sounds like you had no running issues with the engine even with the hot coil.

Back in the first post of this thread you said you replaced the coil..........I guess I'm curious what coil you're using right now. Something like brand and part number or coil primary resistance (like maybe 1.5 ohms as an example)

And.........if you're gonna check voltage from the resistor going to the coil, do it with the engine running and warmed up to get a number that will really mean anything 

 On my boat the coil appeared very hot last year as well, the laser temp gauge for HF said 130 degrees. I thought that was too hot and installed a new flame thrower II epoxy filled coil.  probably overkill but it helped my hot start  issues. At the time I wondered the same question keno is asking now... how hot is hot.

The coil part no. is R117004A, purchased from Skidim for the previous setup with the Prestolite electronic ignition module. Primary resistance is 1.0 to 1.1 ohms (with engine warmed up).

Voltage is 12 volts to the resistor, and 9 volts from the resistor to the ignition coil.
That should provide 12 volts to a new D.U.I. distributor after the resistor is bypassed, correct?

Is that 12 and 9 volts with the engine running?

I think you should have at least 13 to the resistor with the engine running if your alternator is working as it should. And a few volts drop through the resistor

What's battery voltage when the engine is running? What's alternator output right at the output terminal

I took some "representative numbers today on a boat with points and had the numbers below with it running::

14.5 volts at the battery and also the alternator output

13.5 into the resistor 

11.0 out of the resistor

coil temp of 125 ish degrees after running for quite a while. To me that's warm but not hot

These were with a 1.3 ohm resistor and a 1.5 ohm coil so 2.8 ohms total resistance.

For the DUI, I think you'd want up around that 13.5 number with the engine running and the alternator supplying power.

I'm wondering if the alternator is putting out the correct voltage.

it was a nice day for a cruise 

Not nearly as much time as you donated to your friends Cobalt

Happy birthday

Maybe you'll get one of these a little ahead of schedule today

Or one of these too

Have a good one 

With the engine running, there were 14.3 volts indicated at the battery and the heavy orange wire on the alternator. (is that the battery positive wire?)

12 volts at the yellow wire on the alternator.

Thoughts?

Your alternator is working since the battery is at 14.3 volts with the engine running.

The heavy orange wire is the alternator output supplying charging to the battery and supplying the electrical system when the boat is running.

12 volts on the yellow wire to the alternator is low though. It should be up more in the 13.5 range.

That is the excitation to the alternator, it'll work just fine with that voltage supplied to it but.........that voltage is also going to the choke which will be just fine also and the ballast resistor supply. Your points will work OK with that 12 volts into the resistor but the upcoming DUI will be happier with more voltage like the 13.5 mentioned earlier.

It comes from the keyswitch in RUN back through pin 6 on your 8 plug connector and the wires are spliced together as shown in the photo below of that particular section of an untaped engine side wiring harness. It gets to the keyswitch through pin 5 so somewhere in that wiring you're losing too much voltage

You're losing 2.3 volts  between the battery supply and the ballast resistor supply which is a lot. Something around a1 volt loss would be much more normal and would be much better for your upcoming DUI distributor.

You previously checked that you had about 12 volts with the engine OFF and the key in RUN, but you should do the same checks now with the engine running and see where the voltage is being lost. It could be any connection in the flowpath being loose or corroded enough to affect the wires ability to carry load like where the wire connects to the keyswitch or the ignition breaker as a couple of examples

A genuine PCM wiring job

It also seems like he vanished or something before he could put it in or update what his results were or maybe it's backordered or maybe the boat really did drive him to drinking

Buck..............you out there?