1980 SN stalling when hot / won't restart

dentontx87 wrote: Is the coil getting too many amps causing it to overheat? What would cause that if so?

Kevin,
Amps no but too many volts maybe. The voltage needed by a coil depends on the type. There are some that are internally resisted to drop the volts from the nominal 12 and then others that require external ballast resistors to drop the volts. You need to tell us more like has the ignition system been modified from original. EI conversion in the distributor? Considering your question on amps, do you have a friend that's more familiar with electrics that can help out?

Welcome to CCfan. Tell us more about the boat like how you use it. We also love pictures.

I believe the ignition is all stock. I purchased another oil filled coil from the local nautique dealer. I can test voltage, how much should it be getting?

My boat, a 1985 SN 2001, will be used for skiing, wakeboard and tubing. I don't know how to attach photos but it's a sharp boat.

Pete, Pete, Pete

It's time for you to learn how to post a picture from quick reply

You just click on the "full reply editor" (that's the icon to the farthest right that has a diagonal arrow pointing up, then you have all the "full reply" icons and it's the same from there..

I just posted this picture of you in your younger, wilder days using that method to be sure it worked. Nice air by the way

I had the same symptoms you and other have and chased my tail for a long time before I fixed it. I made the same mistakes you're making, so don't take this as wrong, but your trouble shooting organization sucks. You don't know if it's fuel or spark, still.. Until you know which is the problem, or if it's both, you'll be frustrated.
One thing I learned is this. With today's gas and carbs, it's easy to flood the engine when hot. Someone suggested you open the throttle all the way when it won't start but I don't know if you tried that. I would add that leaving it open for 3 or four minutes with the engine cover open would be better at evaporating the excess fuel if that's the problem. Don't pump the throttle, this only causes the accelerator pump to squirt in more fuel. Turn it over for 5 seconds, and wait, don't move the throttle. Don't want to overheat the starter motor.
Try again several times. If it roars to life, it was flooded. If not flooded, perhaps it is starved for fuel. Try putting some into the carb by whatever safe method you prefer.
No start? Put the flame arrestor back on. Move on to electrical. Bring an extra spark plug. Disconnect a lead, plug in the extra sparkplug. Hold the threads against bare metal. Have someone turn over the engine. Is there a nice fat spark at regular intervals?
If not, it's electrical.
I would try going back to points, condenser, and coil wired through a ballast resistor if you have no spark when hot. Sure it's old tech, but with the short hours we actually use boats, they last years.. Give the points a fresh filing to make sure they make contact. At least try this as a test if you prefer.
Lastly, if your or other's carbs are flooding when hot, but work great when cold, it could be too much fuel pressure. The floats can barely hold back the fuel at 4-5 psi when cold, add heat,, and they can leak and flood the engine after it's shut off. Today's gas is not as buoyant (I'm sure there is a more accurate term) as it was in 1980. My fuel pressure has been dialed back to 3 psi with a Holley fuel pressure regulator between the fuel pump and carb. Don't get a cheap Chinese one, they are erratic. This provides all the fuel I need for both my 351 and 454, and never floods after a hot stop.
I'm not an expert or a trained mechanic, this all all from my personal experience with SNs. I'm just trying to help fellow boaters.

MourningWood wrote: Another quick test is float level when running (when warm, if you can get it idle briefly). Do you trailer your boat? I ask because this is very hard on the float levels. Floats bounce, get knocked out of adjustment. More sensitive on 'slanted' carb position.

MW - Just curious how the float bounce would be exacerbated by trailering?   Seems to me that my boat takes a lot harder of a bounce riding on choppy water than it does on the trailer.   I was thinking that the float bowls would normally be full in either situation, essentially dampening any exaggerated bounce of the floats.   Can you help me to understand the logic behind your theory?    I am curious if you have had experience with needing to re-adjust your floats and how often you check them?

(sorry for the total thread jack to the OP), I am open to a PM or a new thread if you were interested in talking it through.

Dreaming wrote: MourningWood wrote: Another quick test is float level when running (when warm, if you can get it idle briefly). Do you trailer your boat? I ask because this is very hard on the float levels. Floats bounce, get knocked out of adjustment. More sensitive on 'slanted' carb position. MW - Just curious how the float bounce would be exacerbated by trailering?   Seems to me that my boat takes a lot harder of a bounce riding on choppy water than it does on the trailer.   I was thinking that the float bowls would normally be full in either situation, essentially dampening any exaggerated bounce of the floats.   Can you help me to understand the logic behind your theory?    I am curious if you have had experience with needing to re-adjust your floats and how often you check them? (sorry for the total thread jack to the OP), I am open to a PM or a new thread if you were interested in talking it through.

Ah yes, but when running on the lake, the floats (and float bowls) have a constant and steady supply of fuel to them, don't they....

Yes, at least annually.
When the boat comes off the lake, the hot fuel will both slosh out the vents and, with a hot motor, evaporate, especially today's fuels. The floats can and do pound out of adjustment. Boat trailers aren't known for an overly-cushy suspension, either.

Another item is the float itself. First, they should be brass, not plastic. Over time, even the brass ones can develop pinholes in the brazed seam. The hotter the fuel, the more these will open up, flood the float, and there you are.

Test: Get a gram scale and weigh the float. Then immerse in boiling water for a few minutes, remove and re-weigh. (you can't see any leak bubbles in the boiling water, hence the scale). If heavier, replace.

Morfoot wrote: beatsmd wrote: SNobsessed wrote: Also, some coils don't like horizontal mounting. The oil inside doesn't cover the windings adequately. What coil do you have? I've been having the same problem with my 1984 Nautique, and (if I'm remembering right) I never had the problem before installing an electronic ignition a couple years ago. At that time, I installed a new PerTronix 45111 Flame-Thrower II 45,000 Volt 0.6 ohm Coil. It's an oil-filled coil, and it is installed horizontally. Could the fix be as simple as just replacing the coil with a new epoxy-filled coil? If so, which coil should I install? Had the same issue with the 88 back in 2008. Didn't realize the coil that I had purchased in 2007 was an oil filled cooler. (I had done the points to Petronix ignition swap over probably in 2005.) Bought a Petronix Flame Thrower n June of 08 and have never had a problem since. (knock, knock, knock )   I do however keep the original points setup in the boats toolbox in case the Petronix fails. Keep in mind you DO have to use a ballast resister with the above coil.

It turns out I was wrong about the Flame Thrower I installed--it is actually an epoxy-filled coil. I can't remember if I removed the ballast resister or not. I'll have to check when I get home from work. If I didn't install the coil with the ballast resister, can I simply correct the installation by rewiring the ballast resister, or do I need to install a new coil (presumably because the old one was damaged by the improper installation)?

The internal resistance built into the coil is .6 ohms while the ballast resistor used is a 1.5 ohm resistor. Pretty sure I installed a 1.0 resistor.

I've heard here many a time where the Pertronix EI system isn't too reliable but I've had nothing but success with it.

I would wire it back in.

I hear you can get pretty far up that creek with points and get stuck too Tim It seems the newer units have more troubles? Or is it because there are less experienced "mechanics" trying to install them? The neighbor who towed us in used to own several gas station back in the day in New Youk City, he was relating his experiences that he had gone thru up to and including of taking the tow truck and rescuing customers that just had a tune up.

tjdarland wrote: Below is my troubleshooting plan. Any guidance would be appreciated! Before next run: > Check anti-siphon valve. I'm not sure that I have one but will check and, if so, I'll most likely remove it completely. Thoughts? Thanks in advance for any help!

I'm not sure why you'd want to remove your anti siphon valve, since it's a safety feature.

Go ahead and remove it and then if you have a fuel line leak between the tank and the fuel pump all that gas in the tank siphons into the bilge till the tank is empty. Nice explosive fuel air mixture just waiting for a spark.

You can probably figure out the rest of what happens

Just helping you stay out of the burn ward or the morgue so you can finish your troubleshooting

Hey everyone. Thanks for all the troubleshooting advice. Turns out my gut was wrong--it was the ignition coil. Easy fix and now she's running like a new machine!

tjd