Good morning from hilton head

[rwappleton]

Our old girl made it like a champ! 22.7 KTS @ 2100RPM just before entering Skull creek.

Generator(ONAN MDKAL 9KW) 445 hours since new starts, takes the load, and runs between one and two hours and quits. Now a little hard to start. Fuel filter has 8-10 hours since change however tanks were cleaned after the change. I can hear the fuel pump,good waterflow, and no breakers popped on the panel. Ideas????? besides changing the filter again which I am going to do in an hour.

Ice maker(u-line) gets cold but no cubes. water is confirmed to the back of the unit.

STBD alternator does not begin to charge until over 1500 RPM but once it does it stays on even at idle???

As Always thanks for the Help,

Becky and Russ

 

[jim rosenthal]

The alternator problem sounds like the voltage regulator inside it. I would take off the unit and bring it to an alternator shop and have them bench test it.

What safety interlocks does the genset have? It sounds like one is tripping and shutting it off. Does the load have anything to do with how long it will run?

 

[Boatnut]

If my memory still works a little bit, when a fault occurs on the Onan units they trip a circuit breaker. It sounds like the unit restarts but no as well as it should. Hopefully Dave will jump in and add some advice. It doesn't sound like a sensor problem. If you are not familiar working with electrical diagrams and have a copy of the manual you cam email me a copy of the diagram I'll do my best to getyou through the electrical circuits. It is possible the diagrams are available online send me the model number an I will look. There are plenty of generator problems that pop up on the forum, I am trying to collect as many diagrams as I can to try and help people out. Good luck, enjoy your trip.

 

[JLR]

I had a similar problem with an Onan on my 56. It turned out to be the ball in the Racor filter not seating properly, or more accurately, shutting off fuel flow to the genset. I also had a similar problem many years ago, also with the Racor, which turned out to be cracked and let air in. Worth a shot and cheap fix.

 

[rwappleton]

Jim,

Alternator is going to visit the local shop in Columbus,GA when we go home.

Jim and Boatnut,

I did not have the secondary fuel filter so I am going to find one now. Load does not seen to effect the time it runs. I have it running now with load and want to hear the shutdown. Both times in the past we were under way and the Purrrrrr of the Detroits drown out the genset .

Was still hard to start and the Racor is clean and clear.

There are only 2 breakers on the control box and neither have been blown.

Got be something stupid. Can the run solenoid get hot and release and cause the shutdown?

 

[sgharford]

Our old girl made it like a champ! 22.7 KTS @ 2100RPM

Man is that dreamy for 43DC - I'm jealous!

 

[saltshaker]

Generator problem sounds like a fuel issue. I had a problem similar to what JLR mentioned. Racor was leaking air and the generator would stall out. Hard to start and would stall out again before running. Next time it stalls out, open the lid on the racor and see if the fuel is to the top of the element. If it isn't, you probably have a fuel issue. Not sure how the sensors shut the unit down from a fault but don't think they would create a hard restart situation. Another thought is that you may have sucked air while running causing the unit to get hot and shut down but again that doesn't explain the hard restart.

 

[carolinacoast]

I had a dirty secondary filter (that I paid a mechanic to supposedly change) that presented similarly. I don't recall if it ran that long though. Anyway, as others have said, likely a fuel issue of some sort.

I now date and add engine hours(except water filters-obviously) with a sharpie to EVERY filter, whether I change it personally or not. That simplifies things for me.

 

[Tinman]

I had a dirty secondary filter (that I paid a mechanic to supposedly change) that presented similarly. I don't recall if it ran that long though. Anyway, as others have said, likely a fuel issue of some sort.

I now date and add engine hours(except water filters-obviously) with a sharpie to EVERY filter, whether I change it personally or not. That simplifies things for me.

Good idea on all scheduled maintenance tasks. Try some 2" blue painters tape, easy to see and removable.

 

[bigbill]

russ, check the belt, i had this same problem and it was a loose belt. didnt pop the breaker, and was hard to restart. dont know why the breaker didnt pop or why it was hard to restart but the tightening of the belt solved the problem.

 

[rwappleton]

UPDATE:

Belt was a little loose removed sound shield(much easier than I thought) tightened belt added a pint of anti freeze. Still hard to start it ran 1+45 and shut down. No shuddering shaking or unusual sounds generator performance appears to be normal. Fuel bowl full, no breakers popped.(I have 2 check generator and check engine). 2 things, engine seems warmer than I think it should be. Anyone know what it is suppose to run at (MDKAL 9.0)? I can not find the number on the Cummins site. Raw water flow appears to be very good. When we were doing the yard work raw water pump was found to be leaking and have a bent shaft (howd that happen?). All replaced and also discovered that unit required 1" sea cock and original for old unit was 3/4" so that was corrected also.

Unrelated is the foam inside the shield is disintegrating. Making a mess for sure and maybe sucking some it the intake as well. Replacement suppliers?

If no luck soon the generator(wallet eating) Gods will be called.

Becky and Russ

 

[Boatnut]

We are king of shooting in the dark here trying to help you out. More info usually helps. You say it is hard to start. Does it crank over normally or is it cranking slow? Does it start and quit several time before it stays running. There are a few things that can cause the problem, it helps to start eliminating possibilities.

 

[saltshaker]

My next guess would be that she's running hot and tripping the high temp sensor. I'm guessing you added a new seacock and hoses with the upgrade? Is there an external or internal strainer that may be restricted? What is the generator thru hull fitting? It can be difficult to see a reduced fow of sea water unless it's significant. The fact that she shuts down after nearly 2 hours might suggest that cooling is marginal.

 

[doc g]

if it shuts down without stumbling just like you just shut it off , it's probably an overheat , or oil pressure shutdown. Bypass the sensors AFTER you confirm normal oil pressure and normal operating temp some other way . Normal temp would be 180 ish if it's like other gens. I had an issue that I traced out to being a loose wire connection in the harness that would (I guess) get hot and allow the fuel solenoid to drop out. .....Have fun ! Hope this helps .............Pat

 

[eze2bme]

If it's temp related and the water flow/cooling system checks out, could the t'stat possibly be going bad?

 

[rwappleton]

The unit ran great before it when into the yard.

Cranks normally good voltage.

when it does fire which takes a while 15-20 seconds it stalls 3-5 times before assuming 1800RPM once running good until 1+45.

new install in 2001 450hours total time

My current guesses are: Bad glow plug/plugs for starting

Thermostat or waterflow issue for shut down

 

[carolinacoast]

Since the seacock was changed, maybe the new inlet hose has a kink, causing an overheat?

 

[Sailor John]

I had a similar problem with my Onan 6.5K.
Appears insufficient water flow caused (eventual) overheat and immediate shut down. Needed to replace the impeller. Easy.
Hope for you too.
Sailor John

 

[Fanfare]

Did the yard paint your bottom? I once had so much bottom paint slathered over my generator raw water intake that it impeded flow. Also wasn't good for the generator impeller.

My hull generator thru hull intake is circular with lots of small round holes about 1/8 in. across. Some holes were entirely filled in with paint, others nearly so. Snorkeled and chipped them out with an ice pick.

I could see that there was not the usual flow of cooling water coming out with the generator exhaust.

 

[rwappleton]

UPDATE: Checked all sensors and seem to be fine. Running temp is 182-185 with lots of water. Cleaned out heat exchanger. Installed new raycor filter.

Sunday, Generator ran for 1.5 hours and stopped during slow cruise. Tried restart and would crank but not run.(no breakers popped) Fuel bowl on raycor was full. Engines were running so could not hear fuel pump.

Waited 45 minutes, very hard to start (1.5-2 minutes of cranking) finally ran and stayed running for 3.5 HOURS WITH NO TROUBLE???????????

My plan is to check connections on the fuel pump unless someone has a better idea? Load makes no difference.