420 Sundancer DA- engine dies without warning

[4Schrecks]

Help please! On July 4, after running fine for about 3 hours total, my starboard engine started gasping for gas (diesel) and then died. Could not get re-started so limped in the last 10 miles. Changed both engines fuel filters and racors. Was able to then get engine started but no power at all. Re-built starboard racor on marina mechanic advice, still no help. Cummins mechanic "bled the system" of air and proclaimed "ok". Took off the next weekend and happened again before even onto the open water. After about 15x, got going again. I didn't want to shut off so ran for 3 hours straight. Next day, no problems at all. Felt confident had "self bled" any little air pockets that may have existed. This weekend, traveled across Lake Michigan from sturgeon bay. Ran fine on way over,came home today and died 1/3 of way home. Limped home (about 45 miles) on one engine. Any ideas? Seems to me to be a lack of gas issue...much appreciate all help. no alarms sounding and all pressures/temperatures are fine. btw...mechanic coming again 1st thing in the am...cha ching...again!

 

[endless seas]

I had something similar a few years ago when our primer pump was not sealing properly and intermittently she would die.

 

[JV II]

If all the Cummins mechanic did was bleed the system of air and that got the engine running again, then clearly there is an air lock recurring. Assuming you don't have a dirty or water in the fuel system, it looks like air lock. If it were the fuel, it would not be intermittent like you're experiencing. Are your Racors full when you open them? It should give you a fuel alarm, though. My guess is air lock. Check your Racor gaskets and fuel line connectors. If your fuel is low in the Racor, that is a good clue.

 

[4Schrecks]

So it is fixed. I thought I would put the dx on here for future reference.

Without getting into the fiasco with the mechanic constantly forgetting his tools in his truck and walking at the pace of a sea turtle back and forth (did I mention they charge by the hour?), and despite reassurances that they would have the "parts we need with us"...NOT!

Ok, to the repair, we took for a sea trial as of course it started right up. Thankfully, about 8 miles into the fog laden lake, it died with him in the bilge watching his gauges and clear line he put on to watch for air. When it died, he found no power to the fuel pump adjacent to the engine filters so he diagnosed as a bad "fuel shut off solenoid". Had to creep back where he assured me he had one in the truck...again NOT! Turns out the closest one was in Memphis, (I am in sturgeon bay wi). Overnighted and off work and back to the boat the next day. He replaces and has the engine running when I arrive. Still confused as to why it would occur intermittently, I asked him to "humor me" and check the wiring. He laughed but did anyway and guess what, found a broken power wire leading to the solenoid! Instantly proclaims, "I found your problem" and makes a new wire. Subsequent sea trial with new wire and solenoid was perfect!

So, I now have a spare solenoid and a new wire. I think, and he agrees, that the wire was the true culprit! I will try to post pictures of the solenoid for future reference for everyone. Thanks for the input and possible causes.

 

[gerryb]

Thanks for taking the time to close the loop on this one. I often take the wiring for granted as well and jump right into replacing parts.