Starboard engine will crank, but not start

[chris41483]

I am in desperate need of help. I am more frustrated than I have ever been.:huh:

My starboard engine will crank over, but will not start. You can see the injectors fire when the key is first turned to the on position, and hear the fuel pump run, but then they do not fire when the switch is in the start position, although the engine in deed turns over.

One of the reasons I like the twin engines is the ability to swap parts for the sake of diagnosing a problem. I have swapped distributor pick ups and ecm's with no effect on either engine (port still fine, starboard still dead).

I started unplugging sensors on the port engine to see what it would start without, and then repeated the same test on the starboard, to no avail.

I ran a jumper from the battery pos. to the coil pos. to ensure the ignition system was powered up, and this had no different result.

I then checked the tach and synch guage signal wires for shorting to ground, and that was not an issue.

I have run out of ideas. I was hoping someone here could either give me a new idea, or possibly poke a hole in an assumption that I may be making wrongfully.

I got frusterated, and went in for lunch, and when I came back, it fired right up! I let it run for a few minutes, turned it off, and when I tried to start it back up...nothing!

Thank you in advance for any help!!!

P.S. The port engine seems to have this same problem intermittantly, but only if I am miles from shore:smt013, and after some time passes it will start back up. It never does it on the trailer, or at the marina, and I have never been able to find what I have begun referring to as "my electrical gremlin"

 

[ohsnow]

Does your engine shut off while running on it's own?
Had a similuar problem on an older 21' SRV. Anti Siphon valve was screwed.... At times no fuel would flow, crank but not turn over.... then she would go...
Not sure if this helps?

 

[Presentation]

Sorry if you already tried this.

Did you take it out of gear (push the black button on the throttle at the helm) and manually advance the throttle stick, resulting in you bypassing the IAC then try starting the engine?

 

[chris41483]

Thanks guys for the quick reply! Yes, I tried the throttle advance, but nothing will make the injectors fire while cranking. The coil is not firing either b/c it will not start with ether. It seems as though the computer does not know what is going on, or where the engine is in its cycle, which is why I swapped the dist. pickups, but still no luck

 

[Redhook98]

Have you looked at your Reverse kill-switch? This kills the motor for a split second when you switch the gear lever into reverse.

 

[chris41483]

I unplugged it on the one that runs, and it still starts, so I unplugged it on the one that does not start, and it still did not start.

We are talking about the one on the starboard riser, correct?