vacuumbed
Salt Lake City, Utah
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Joined: 03/03/2006
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This is a new problem that started on my 1996 Onan 7.5 diesel genset. This is an open genset, not in a metal box like the newer ones.
When you hit the start button, the genset starts but then quits. The start solenoid (Not the one on the starter, but the one that controls the engine shut off) is working properly. When I connect 12 volts + to the solenoid from a different source, it will start and stay running.
When I hook my test light to the start solenoid, it gets power when you hit the start button but then gets no power when I release the start button, and the engine stalls. The solenoid has to have power for the engine to stay running until you hit the stop button.
What could be wrong? I'm thinking it's something in the electronics for the start circuit.
Thanks in advance.
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vacuumbed
Salt Lake City, Utah
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**UPDATE**
The start solenoid and the fuel pump are on the same circuit. Whatever device is responsible for giving them power while startup is not working properly. If I take a jumper wire with 12 volts + and touch the start solenoid just for a second upon start up the engine will stay running. Here is a You Tube video of what happens.
You Tube video link
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vacuumbed
Salt Lake City, Utah
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Here is a picture of the start solenoid I'm referring to and the control box. The wire with the yellow crimp on connector is the positive side of the solenoid. That is where I put power to get the generator to stay running.
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Hjudge49
St. Augustine, Fl.
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Joined: 08/15/2007
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That's not actually a "start" solenoid, but the engine shutoff solenoid. You have a wiring problem between the switch and the solenoid, probably a bad relay, but you really need a wiring diagram to find it.
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SCOMP225
Brownsburg,Indiana
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Joined: 12/08/2002
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That's a DKDFJ.
Make sure you (I know this may sound dumb) Oil level is up.
Check the Oil pressure switches above the push pull solenoid and make sure their wires are connected and tight.
Make sure the wiring on the rear of the solenoid are on the correct terminals. Do not force start it by adding 12V to the solenoid.
Trace the wires back to their source ( IE control box).
I have all of the schematics if you need them.
Chuck
1992 American Eagle
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SCOMP225
Brownsburg,Indiana
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Did some quick research and You have the updated DKD with the electronic control board verses the older transformer type.
In your picture above the larger solenoid is the Starter solenoid.
There are 2 Bosch style relays just below that are marked K13 and K14.
K13 is the preheat Relay and K14 is the Fuel solenoid.
K14 is the one I'd be looking at for this issue.
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vacuumbed
Salt Lake City, Utah
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SCOMP225 wrote:Did some quick research and You have the updated DKD with the electronic control board verses the older transformer type.
In your picture above the larger solenoid is the Starter solenoid.
There are 2 Bosch style relays just below that are marked K13 and K14.
K13 is the preheat Relay and K14 is the Fuel solenoid.
K14 is the one I'd be looking at for this issue.
Oil level is good, I just changed the oil.
I replaced the K14 relay with a known good relay, no change.
Also another noted issue. When the generator starts, there is 118 volts leaving the generator breaker. However, it takes about 36 seconds for anything inside the coach to get 110 power.
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SCOMP225
Brownsburg,Indiana
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Ok- K14 Relay is out of the equation now.
Next I see in the picture that you wired the fuel pump into that new wire terminal. That's ok unless you ever need to change the pump. because next I was going to suggest disconnecting the pump as it may be drawing too many amps to permit the Solenoid to throw out.
118 volts A/C is fine-- there is a time delay Relay in your coach transfer switch for the 30 seconds or so and that is all normal.
You need to hook a digital volt meter to that B+ terminal - attempt the start and read the voltage. With the Pump wired and without.
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vacuumbed
Salt Lake City, Utah
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When I check that circuit with a test light, power drops when the start button is released.
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snail
south west Florida
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Joined: 08/22/2003
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I had a very simular problem with our 1995 Onan gas genny. The problem turned out to be the genny controller. If I remember correctly on these units the genny serves as the engine starter. Once the unit starts it then switches to a generator. If the controler fails, the default is to shut down the engine.
After installing an new control module, everything worked fine.
good luck.
DRIVE A 2001 NEWMAR DUTCH STAR WITH 330 HP CUMMINS AND TOW A RANGER 4X4. TRAVEL WITH SPOUSE AND PET TINKER BELL OUR CORGIE.
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