posted 07-05-2009 12:33 PM ET (US)        

The engine is a 1998 Johson 115/V4 60 degree loop-charged engine (J115SLECM).

On Friday afternoon we took the boat off the mooring and it started up without any problem. Having not been on the boat for a two weeks, we let the boat idle at the dock for about 10 minutes in hopes of charging up the battery and running some fresh fuel through the carbs. The motor was shut down and ten or fifteen minutes later would not restart-- there was just a faint clicking/whirring noise from under the cowling. We thought the battery had died so we ran out and bought another one. An hour later we installed the new battery and the engine started right up. As expected the system check ran the self check and everything appeared to be clear -- however, the tachometer was not working. Thinking this was simply a matter of a loose cable, we headed out for a short cruise. A half hour later, running at moderate speeds, the motor surged three times and died (luckily within a very short distance to our mooring).

The next day we check all the fuses (all fine), cleaned and reconnected all of the battery wires, replaced the spark plugs, checked the fuel filter, etc. We turned the key and the engine fired right up. Accompanied by a chase boat, we went out for another cruise and the engine died again after about twenty minutes -- this time at low rpms and without any real surging. We towed the boat back to the mooring, waited an hour and it started right up again, but died within minutes...

A few considerations:
- The boat has only been run twice this season, both for less than an hour
- The first day were running on a half tank of stabilized gas from last season. The second day we filled the tank, but it did not seem to have any effect
- As I said, the tachometer was not working, but had before
- This season, I had replaced the fuel filter with a racor water separator, but took it off and reinstalled the older OMC one to see if it was restricting fuel flow -- it did not seem to be the issue
- I posted another message two weeks ago inquiring as to a system check warning I had gotten just before I headed for home. It is here:

I think this has surpassed my very humble abilities. Is there anything leaping off the page here, or should I haul the boat and bring it to my local OMC guy? I've done some searching on the site and reviewed my shop manual, but am unable to narrow it down. Perhaps it is a faulty Powerpack and the rest of the issues are just red-herrings?

posted 07-05-2009 12:36 PM ET (US)            

http://continuouswave.com/ubb/Forum4/HTML/006762.html