New Cummins Onan MDKBL won't start

[Vincentc]

The newest component on our new to us 1983 43 DC is giving me the most problems. We have a 2008 9kw Cummins Onan MDKBL which has refused to start 3 times in the last 2 weeks. I bought the boat this month and was advised that during pre purchase survey the generator failed to start and the selling installing dealer repaired it.

We took delivery 8/2 and started the generator without problem. We left Sarasota FL for Pascagoula MS on 8/4 and the generator ran fine and constantly till 8/6 when I stopped it to change oil. When I attempted to restart nothing happened other than a flashing light fault code of 32. The manual said check starting battery and connections, but they were fine.
We were in Carrabelle, FL and no Cummins/Onan dealer was available, but located an independent mechanic who very kindly stopped a job he had going anc came to help. He identified and replaced 2 faulty relays, and the generator started right up and restarted after subsequent oil check stops during the remainder of our 9 day cruise home.

Yesterday, after I checked the oil and went to start up, again nothing happened. Same fault code 32. As it was a Saturday and we wanted to go out, I attempted to replace the relays myself. Purchased two 30 amp 12v 5 prong relays at AutoZone (Duralast 19273 MR76) which appeared to match the two that had previously been replaced in the control box (plug in's Marked "K3" and "K4") I put them in and no luck. No starter action and same error code. The relays removed in Carrabelle are marked “CB1-12v ACB13201”

I will be talking to the local Cummins Onan dealer tomorrow but would like to learn something more about my problem and in particular why these relays are failing and if there an underlying Onan problem here. Spoke to a repair shop mechanic in Carrabelle who commented that Onan had a lot of problems with relays.

Any thought experiences regarding the solution to these issues. Assuming the relays are the problem, can anyone tell me what the correct relay(s) is/are for these plug-in. I am also wondering if perhaps there are other relays that failed and I am looking in the wrong location. I watched the mechanic replace the two relays from a distance since the generator is located in a cramped and inaccessible location and may have misapprehended which relays he replaced. Perhaps I have a new problem.

Thanks,
Vincent

 

[Finalee]

I had a similar experience with my 2006 13.5 kw Onan. Turned out I was hitting the red emergency stop switch without realizing it while doing my preflight checks. The switch is simply an on / off type on the upper rr corner of the unit . I still accidentally hit it on a regular basis , but now know it is the problem and just switch it back on.

 

[REBrueckner]

It would be interesting to know what repair was made the first time....whether the second relay repair was a repeat or something else...


Consider that a broken or loose wire might be the cause....guys replace a component and in so doing jiggle a wire so contact is restored...things work until genny vibration again breaks contact....things go dead....

For the future, always have the repair technician describe what he thinks was wrong and exactly what he did to fix the problem...what was replaced...
log them for reference.....

 

[Vincentc]

Thanks for the comment.

I don't think I am hitting the stop switch. This morning, I did speak to the dealer who installed the gen and repaired it last before my purchase. The service report indicated that there was a loose ground. When I can get back to the boat, I am going to go take a second look and try to locate the ground.

I am presently waiting on a call back from the dealer in my home area.

 

[REBrueckner]

"The service report indicated that there was a loose ground..."

not surprising!!! Good for you for checking....

Are there any wires in the vicinity where you might have touched/disturbed/jiggled them during an oil change? For example, a wire to my fuel solendoid passes right next to my oil filter and is always in the way when changing my filter...

If you have a trouble shooting brochure, check for appropriate start voltages...if you know how to use a voltmeter.

Is your genny failing to turn over..which is what your description sounds like, or is it cranking but failing to start?? either case will tell you where to start testing....forexample, if it's not turning over, the start solenoid in the control box which engages the starter solenoid is not activating...

IF the starter IS cranking, but not starting, then likely the fuel solenoid is not getting battery voltage and you should start there....

 

[Vincentc]

The starter is not engaging at all.
I press and hold the start switch and the generator goes though some type of diagnostic then is suppose to start cranking. However nothing happens other than a very faint clicking sound. The sound is definitely not the starter engaging.
We made do last night without generator and had 12 people aboard for a friends birthday. Used the oven before we left shorepower and everyone had a great time. About the only issue was the lack of interior 12v lighting and unmaterialized concern regarding no power for the refrigerator. I will study the hatteras owners manual to see if there is something I am missing regarding inside lights.
A local dealer says he may have someone out Thursday AM. I will probably wait to let them address the issue with a lasting solution.
Thanks,
Vincent

 

[Fanfare]

Wait--no 12v interior lights? That seems strange...

 

[Vincentc]

I found the 12v lights. There is a switch in the stairway to the aft cabin that has to be on for the switch in the salon to the left of the steps up to the aft deck. I didn't realize that and when I flipped that switch while the generator was off and nothing happend I assumed it was a 110v light.

There is a lot to learn. Thanks for the comments.