OMC 5.0 Backfires

[gmckenna]

Appreciate anyones opinion...<br />I have a 1987 OMC 5.0 that starts fine and idles fine but at power it pops through the carburator with a corresponding loss in power. It smooths out real soon but then pops again.<br />I have changed the points, rotor, condenser, cap, water separator (no water) and the in-line fuel filter...still the same. I adjusted the timing to 10 BTDC and the points are set to .018? <br />I took it to the shop and they ruled out a valve problem and suggested that it is a "power module" In my experience a "power module" sounds to be part of electronic ignition system.... remember, I have points and condenser...doesn't that mean I wouldn't have a power module?<br />Any suggestions appreciated!

 

[Stanp]

Re: OMC 5.0 Backfires

an '87 omc, you must have standard ignitionm, but I'm not entirely sure. The one component you did not mention was the coil. Backfiring sounds to me like a bad coil. check the coil to see if its leaking fluid. THey are cheap to replace, I'd just do it. Oh, Has anyone put new spark plug wires on recently. If so, they may be put on incorrectly - that causes backfire (and will ruin the engine). Best guesses.

 

[LANDSCAPE]

Re: OMC 5.0 Backfires

response to back firing. I had same problem with my 89 seaswirl. Went through many trouble shooting procedures. Finally found that condensors @ 2.79cents can be bad form factory try a couple of new ones. I went through 3 before engine ran fine.