1984 sn2001 cuts out at higher RPM? Help!

In a ski boat I'll take reliability over maximum performance any day. Excessive current and heat will eventually kill electronic components.

Called Vince.

FYI, Vince was great, spent >5 minutes on the phone with me, reading off the Prestolite EI Installation instructions & helping me interpret them, all with no sale in sight.

Presotite recommended a coil with 1-2.5 ohms primary resistance & no ballast resistor in circuit.

According to Vince, most Prestolite EI module failures happen when guys put Accel or blaster coils with it

He said if my coil wasn't getting hot, it is OK as is (without resistor).

Just for kicks, I might use my IR thermometer & check coil both ways.

Hope this helps everyone!

Chris, the Prestolite may be like the Pertronix Ignitor II in which it doesn't require a minimum resistance, but I suspect it does.

No harm in scanning and posting copywrited material.

Hollywood wrote: Great! Let me know when you get it.

Tim,
Fax or email, when you do get it in, make sure you post it. Also create a link in the FAQ thread.

He can probably fax it to you- they've sent me diagrams in the past. Or maybe they can email it now. You can try communicating with them telepathically, but it's probably quicker to call.

No the Dead Sea scrolls have been found. I think they were stored in the Amber Room.

Wouldn't surprise me either.

If you want the actual instructions, call SkiDIM! I never installed one, not sure if I ever saw the instructions with my own eyes... Though I did have a few conversations with Vince regarding general PCM wiring (not specific to EI), it's been 10 years since I created that diagram/picture.

Sounds like you've isolated where the problem is. Carb sounds fine. Good luck.

Not having seen the exact instructions in a number of years, I would not be so quick to blame any perceived failure rate (be it normal or accelerated) on poor documentation.

And as a result we've heard of plenty of failures due to [a lack of] poor instructions and understanding.

I'd really like to see (and dispute) the original Prestolite instructions with the blanket statement of "bypass the resistor" with no mention of coil resistance.

HW, will do, all it takes is to swicth the terminal    Not that I don't believe you, but wanted to read it myself. Haven't yet found any documentation on the old Prestolite EI but did find this post from TRBenj on (gasp) the mastercraft forum:

In my experience, the Prestolite/PCM kit usually has you bypass the resistor, while Pertronix kits will vary. It is also important to match the coil to the module. Again, I recommend that anyone installing EI follow the instructions in their specific kit.

SNobsessed wrote: The way 79 'splained it was that the EI circuit would limit coil current at the low RPM (which is why you need a resistor when using points).

Eh, I'm not going to take his word on all EI modules. These manufacturers seem to be pretty specific about what resistance they want.

SkiDIM currently sells the Pertronix Ignitor II, which in their product description does state to bypass the resistor. Pertronix Ignitor II instructions agree.
6. The Ignitor II ignition can be used in conjunction with most ignition coils rated at
0.45 ohms or greater.
7. All external resistors must be removed to achieve optimum performance from the
Ignitor II ignition system.
http://www.pertronix.com/docs/instruction-sheets/91141.pdf

HOWEVER, some of you may have had the Ignitor I, which DOES state a minimum resistance.
Pertronix Iginitor (the first edition) installation instructions:
4. Four and six cylinder engines require a minimum of 3.0 ohms of primary resistance and eight cylinder engines require a minimum of 1.5 ohms of primary resistance. Do not remove resistors if the coil primary resistance is less than specified.
5. If your Ignition coil has the recommended primary resistance, remove or bypass all external resistors.
http://www.pertronix.com/docs/instruction-sheets/1141.pdf

Hot-Spark:
Coil Warning: DO NOT use a low-resistance or an HEI-style coil. 4- and 6-cylinder: Use a coil that has resistance in the primary circuit of at least 3.0 Ohms (Ω). 8-Cylinder: Must be used with a coil that has resistance in the primary circuit of at least 1.5 Ω. Using a coil with insufficient primary resistance can cause the ignition module to overheat and misfire until it cools down again, or fail prematurely, which will void the Hot-Spark ignition warranty.
http://www.hot-spark.com/Coil.htm

Mallory:
NOTE: The purpose of resistance wire between the ignition switch (12V) and the ignition coil positive terminal is to restrict current flow through the ignition coil. Failure to use resistance wire will eventually destroy the Ignition Module.
http://prestoliteperformance.com/media/instructions/mallory/Mallory_Instructions_unilite_distributor_37_38_45_47.pdf

All that said, know what kit you have and what they want. Seems as though Pertronix Ignitor II is the only one that is safe to bypass the resistor no matter what coil you are using. And now I think most of you burnt up your EI modules on your own. SNobsessed, if I were you I'd wire back in the resistor.

what is a back flow?

hollywood is right.