Weird problem, no spark

emccallum wrote: Thanks! Glad you didn't say "tubing"

Oh wow, must have been too busy wakeboarding. :)
Yes if I remember correctly that was it, ran fine again!

Thanks, hope to have it here by Monday. Then hope the boat runs fine again!

Seems like it's the distributor module that's bad.
What do I look for to find another one; is it Prestolite, Ford, PCM, ...?
Regular car part or marine-specific?
Thanks!

SNobsessed wrote: Sander - The resistor is just bypassed. I did this to my boat, as the prestolite EI is happy with full 12V.

But the coil may not be and it could overheat causing the problem described.

Take a look at the coil see what it says about external resistors... along with all the rest...

OK, thanks, no worries there then.

Would a battery cable that black be able to cause the issue?
I cleaned the top of it a bit, as good as I could, but don't know how far in it's that black.

Here's what the negative cable of the battery looked like:

Tried to replace it, but no such thing around here. Skidim, here I come again. ;) 'Till then gotta keep going with this one I guess.

This is how the resistor is (not) connected. Been like this for quite a while actually, 2 years probably, maybe even more. I remember some mechanic put it this way, when it is hooked up as it should be, the boat won't start. Bad resistor?

TRIP wrote: We'll have a multimeter tomorrow morning. Still wondering if when Pete's jumper-tip works that means it IS inside the distributor or is NOT?

OK, my best guess. The negative pole of the coil has to be grounded (wire to dist. case)to complete the circuit through the primary and secondary windings where 12 volts gets turned into 20,000 volts. When the points open or electronic module signals, the negative ground is lost, collapsing the magnetic field in the coil, inducing the "firing" of the coil.
Since your ground is iffy, sometimes the coil won't get charged up until you ground it with a jumper. Then it works until enough resistance (heat) builds up at the ground point (distributor hold down)to interfere with the grounding. Any semi bad connection from dist. to ground will do. I would sandpaper the wire connectors, bolt, washer, etc.,until I had about .7 ohms resistance (depending on the resistance from the meter itself, mine reads .6 just touching the leads together),from the negative coil to the block. About 10 ohms will be high enough to mean NO ground connection. Set your meter on ohms (omega sign). Some meters have 200, 2000, 20k settings, some set the range automatically. I set mine at 200 (zero to 200)for resistance testing, 20K for coil center testing.
BTW, all my coils have different values both on the low side (neg to pos 1.5 to 2.1)) and center to either neg or pos 10k to 15k.but work fine in those ranges with points and resistor.
I wouldn't trust an electronic module that got hot like yours (from a poor ground)to be trustworthy either.
Always check ohms with the power (key) off, or you'll be buying a new meter. At least the cheapo ones like mine.

There's no need to pull the distributor out, it only grounds through the hold down piece, very likely the problem. Sanding the contact surfaces will ensure a good ground.
Get a multimeter and read the instructions over until you understand how to test for resistance (ohms)and volts. Otherwise you are working blind.
For the cost of a pizza, you can see what's actually happening.

SNobsessed wrote: 8122pbrainard wrote: You can simulate the point set (or electronic module) opening and closing with a jumper between the - terminal on the coil and the engine block. Just touch the - terminal and then when you break the connection you should get the spark. This is the test I would do at next failure - Then you will know if it is inside the dizzy or not. Use a known good spark plug wire coming out of the coil to eliminate the dizzy cap/ rotor too.

Time to revive this thread! Problem only occurred occasionally, and I could always 'fix' it thanks to Pete's tip (jumper between negative and block).
Now it happens all the time however, sometimes every 30 seconds.

Anyway, I now know that using that jumper solves the issue. Like it 'breaks' a short circuit, and everything works OK again.
What I don't know is if that means the problem is in the distributor, or not(?).
I also noticed that the module (if that what it's called) inside the distributor gets crazy hot.

TRIP wrote: I do need to get a volt-meter or ohm meter or whatever it's called, and learn how to use it.

I think Pete just shed a tear.

Yup, will do!

It does have an external resistor so that could possibly be it too.

Thanks again!

I would suggest making sure you don't have any ground wires loose that could be getting bounced around causing an inconsistent ground or a frayed wire that is shorting out. Also though resistors rarely go it does happen and can start out by acting up just now and then. Though with electronic ignition you probably have an internal resistor in your coil. If not I believe you can get a internal resistor coil and bypass your old one. What kind of pressure are you getting from fuel pump. (that is more of an after thought by the sounds of your problem though)

I agree with that. But an hour or two of wakeboarding would be way more than enough time to make a coil hot. Lot of heat built pulling weight at 18-20 something mph. But you never know if its just starting to give out. You could run boat to operating temp then shut off and if you have points you can turn key to on position and manually open and close points with a screw driver and you should see a spark. I have heard resistors rarely fail but would definitely start back there and work forward. Sorry no help if you have electronic ignition, have to learn more about that myself, switching away from points this spring.

True. I did forget to ask whether he electronic ignition or not