I have a '82 Bayliner with a Volvo Penta AQ125A engine. There has been a recurring issue with burning out coils. It seems that you can go out on the lake 2-3 times before it fries. We get towed to shore, replace the coil, and within minutes are bounding accross wavetops once again. Just before the coil dies the engine starts skipping and sputtering and the tach jumps all over. If you open up the throttle it will rev and then bog and rev and then bog...rinse, lather, repeat. This goes on for a while until you are about 400 feet from shore and then the engine dies and will not start again. We get towed to shore, replace the coil, and within minutes are bounding accross wavetops once again. When we go to replace the coil it is almost too hot to touch. Needless to say this has been a frustrating experience. I have tried to convince my father to name the boat "Tow ME!", but he just shoots me a dissaproving look that only a father can.
We have tried factory coils, aftermarket coils, coils with internal resisters, coils that need external resisters, red ones, blue ones...all burned out after a few hours of use.
What could cause this issue? Bad condenser? Incorrect points gap? Bad coil ground? Gremlins? As much as I enjoy crawling into a hot engine compartment while bobbing around at the mercy of the waves as the landing fades into the distance, I would like to find a solution to this issue. It's getting expensive to bring a spare coil with me every time I use the boat. Thanks in advance for your help.