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Topic: Onan emerald plus 4000 genset in '93 LD 23.5 (Read 541 times) previous topic - next topic
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Onan emerald plus 4000 genset in '93 LD 23.5
My genset starts and run just fine but does not provide power as it should to the coach.
I have done the obvious checks like breakers (control panel and on the gen itself) and
still no juice to the coach.  I can't locate a transfer switch if there is one.  Also, can't find
if the genset is hardwired to coach or is there a plug that should be checked/cleaned.
Any suggestions welcome....I'm stumped. Thanks, D. Larson
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #1 –
There is a circuit breaker on the generator that is the usual cause for this. If the generator is running it is producing power. 
Harry 2006RB
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #2 –
I have the same Generator in my '94 LD30'   I'm working a problem on mine where it will start but it stops when you let go of the start switch.  The light doesn't come on.  for some reason if you play with it long enough it'll start working normally.  I'm changing out the switches and circuit board...

In your case, does the light on the internal switch come on?  have you tried measure the voltage on the output to see if there is any coming out of the generator?
Time spent camping is not subtracted from your lifespan
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #3 –
Quote from: DesertDust  - 
I have the same Generator in my '94 LD30'   I'm working a problem on mine where it will start but it stops when you let go of the start switch.  The light doesn't come on.  for some reason if you play with it long enough it'll start working normally.  I'm changing out the switches and circuit board...

In your case, does the light on the internal switch come on?  have you tried measure the voltage on the output to see if there is any coming out of the generator?

Unlike the later 4000 series, the Onan Emerald has an oil pressure switch. If it gets sludged up it can be fussy when engine is cold and can keep the engine from running when not holding the starter button.   Probably not your issue but when you mentioned that after playing with it long enough it starts working normally that was the first thing I thought of.   I was able to just clean mine. 

(I don't remember if the light was on or not.)
1995 26.5 Island Bed
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #4 –
Quote from: MarkT  - 
Unlike the later 4000 series, the Onan Emerald has an oil pressure switch. If it gets sludged up it can be fussy when engine is cold and can keep the engine from running when not holding the starter button. 

Well it's worth checking, I've got a new one coming as part of a deep-service    thanks for the tip
Time spent camping is not subtracted from your lifespan
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #5 –
Hi—like you, my genny (‘07 22’TK) was producing power but no power to the coach.  The transfer switch is located on top of the converter.  With the genny running, I gave the transfer switch a good rap thinking it would trip the switch.  No such luck!   I finally got power by unplugging the coach from shore power and letting the genny run.  After quite a while, the transfer switch sensed the need for power to the coach (since the shore power was disconnected) and viola’ I had power to the coach.   The genny had not been exercised by the former owner for quite some time.  I had the genny serviced to make it run, but it took all of the above to switch to power the coach.  Now, after it has been used and exercised regularly, it switches almost immediately.  Good luck!
2007 'TK 24'
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #6 –
There is supposed to be a twenty second delay to let the generator engine stabilize before hitting it with a heavy load. (the generator).  RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #7 –
Ron, ours will run for about a minute before the switch over. We have a replacement transfer switch and it is remoted
up under the kitchen sink.

Jon
1994 MB
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #8 –
Quote from: MarkT  - 
Unlike the later 4000 series, the Onan Emerald has an oil pressure switch. If it gets sludged up it can be fussy when engine is cold and can keep the engine from running when not holding the starter button.  

That was *exactly my problem.  I replaced the oil pressure switch and problem solved.
I also found a youtube video that addresses this problem and has a nifty was of determining for certain that the switch is the problem..

https://youtu.be/GBED2qjKoFE?si=juYyU0NXfz5wR9fn

Time spent camping is not subtracted from your lifespan
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #9 –
Quote from: DesertDust  - 
That was *exactly my problem.  I replaced the oil pressure switch and problem solved

Well.. Almost.   I replaced the oil pressure switch, oil and filter, and circuit board. and it started right up.   BUT

now after about 6-7 minutes it shuts itself off, just like someone pressed the off switch.   Sometimes it will restart, sometime it wont, at least for awhile.   I'm going to check on the condition of the wire leading away from the switch but...

the compartment it's in is so  tight that the top of the generator is almost touching the ceiling of the compartment so, I cant get in there to change the carb or back spark plug.   It looks like my only choice is to drop the generator at least a few inches... anyone done that before?

Time spent camping is not subtracted from your lifespan
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #10 –
Hi Desert Dust;  You didn't say how many hours your generator has.  I'm always surprised that people don't realize that you need more than a quarter tank of gasoline to run the generator.  The dip tube for the genset doesn't go all the way to the bottom of the tank. That is so it won't drain your tank to zero and leave you stranded.
   Also your Emerald Plus has an altitude adjustment and a winter/summer setting. I could see that affecting your engine if the choke shuts off after a few minutes, and leans out the mixture too much. 
    So the AI says: "Ensure the generator has enough fuel, the oil level is correct, and the air filter is clean. "  Something to start with.  I'm up to 135 hours now, about 80% maintenance running.  I skip maintenance if I've recently run it for real.  (I have forgotten to adjust for altitude and summer!)
    Last but not least, you could have the dreaded " worn out fuel hose" issue where cracks in the line from the fuel tank make it hard to get gasoline into the genset carburetor.   
    The companion has a write up on this: The Lazy Daze Companion: Generator      RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #11 –
I guess the question is if it's surging before shutting off.  You said off like a switch.
  My 2000 started what I think is the dreaded fuel line issue in Sonoma a few weeks ago.  Can't tell yet if fuel line or pump.  I was hoping the fuel line repair had been done as it appears the tank was dropped at some point.  Thanks for the link to companion Ron.  BTW, mine will start up if I fiddle with running fuel pump for a minute.   It either stays on for whatever I need, an hour plus or shutdown within a minute but with surging so appears fuel related which is why I ask OP if surging.

Ramon
2000 Mid-Bath
2012 Lance 830 Truck Camper/2006 Cummins Dodge Ram Megacab
1985 Multi Plan - Donated to the American Breast Cancer Foundation.
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #12 –
Quote from: RonB  - 
Hi Desert Dust;  You didn't say how many hours your generator has.  I'm always surprised that people don't realize that you need more than a quarter tank of gasoline to run the generator.  The dip tube for the genset doesn't go all the way to the bottom of the tank. That is so it won't drain your tank to zero and leave you stranded.
   Also your Emerald Plus has an altitude adjustment and a winter/summer setting. I could see that affecting your engine if the choke shuts off after a few minutes, and leans out the mixture too much. 
    So the AI says: "Ensure the generator has enough fuel, the oil level is correct, and the air filter is clean. "  Something to start with.  I'm up to 135 hours now, about 80% maintenance running.  I skip maintenance if I've recently run it for real.  (I have forgotten to adjust for altitude and summer!)
    Last but not least, you could have the dreaded " worn out fuel hose" issue where cracks in the line from the fuel tank make it hard to get gasoline into the genset carburetor.   
    The companion has a write up on this: The Lazy Daze Companion: Generator      RonB

Lordy, the tank is full.   what's weird is after a few mins (sometimes right away) it will start again and run normally.   I'd love to do more investigating but I'm going to need to drop the unit down at least a few inches to get to anything close to the top.
Time spent camping is not subtracted from your lifespan
Re: Onan emerald plus 4000 genset in '93 LD 23.5
Reply #13 –
Hi Ramon, and DesertDust: There is a mechanical governor for speed regulation, near the top of the engine that is reachable from the side door.  Many many years ago I had a problem with surging, and I sprayed the speed control linkage with some WD-40, followed by some quick lube spray. It hasn't done it again, but of course I don't run it enough to be sure that that was anything, or something!  The RPM is supposed to be steady, but load on the generator will change the RPM just for an instant and the engine will return to speed. Most noticeable when the A/C compressor switches on and off.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB