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Topic: 1992 Onan diesel no crank (Read 556 times) previous topic - next topic

1992 Onan diesel no crank

Good morning all,
I have had to use my 92 GV this past week, and have run the generator several times
successfully.  I subsequently had to disconnect the battery cables and charge each on separately as
they discharged over night.  I am not on full elec. shore power yet.
After charging, the Onan genset will not crank.  I makes a sound and trips the control
switch located on the generator.  Any suggestions out there?  How do I test the
solenoid?  Thanks in advance
1992 Silver U300 40
DD 6V92 Allison
95K miles

Re: 1992 Onan diesel no crank

Reply #1 –
If the generator was working before you removed the battery cables then I would start there.
 Are the connections clean and tight?
Did you brake a cable at one of the ends while removing?
Recheck the ground connection.
Are you sure that the cables are hooked up correctly? (like + to +)
If the batteries are loosing charge that quick they may not have enough amps available to crank the engine. This may cause an over load on the control board.

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: 1992 Onan diesel no crank

Reply #2 –
Quote from: Yurre –
Good morning all,
 I subsequently had to disconnect the battery cables and charge each on separately as
they discharged over night.  Thanks in advance

Are your batteries 6 or 12 volt?
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: 1992 Onan diesel no crank

Reply #3 –
Quote from: Pamela & Mike –
If the generator was working before you removed the battery cables then I would start there.
 Are the connections clean and tight?
Did you brake a cable at one of the ends while removing?
Recheck the ground connection.
Are you sure that the cables are hooked up correctly? (like + to +)
If the batteries are loosing charge that quick they may not have enough amps available to crank the engine. This may cause an over load on the control board.

Mike
Hey Mike, battery connections are all good and fully charged now.  The detroit cranks and runs fine.
I am going to try the solenoid first.. Not sure why it is flipping the control switch breaker though.
1992 Silver U300 40
DD 6V92 Allison
95K miles

Re: 1992 Onan diesel no crank

Reply #4 –
Quote from: Old Toolmaker –
Are your batteries 6 or 12 volt?

They are 12 volt.  Three of the large one.  Like I told Mike, they crank the Detroit
no problem.
It's definitely a Gen. problem.  Hopefully nothing major.
Thanks,
1992 Silver U300 40
DD 6V92 Allison
95K miles

Re: 1992 Onan diesel no crank

Reply #5 –
Quote from: Yurre –
Hey Mike, battery connections are all good and fully charged now.  The detroit cranks and runs fine.
I am going to try the solenoid first.. Not sure why it is flipping the control switch breaker though.
The engine batteries should be seperate from the house batteries.  At least on my coach it is.  The generator starts off of the house batteries.  Check your house batteries.  You can also use the boost switch to start the generator.
John M.
John & Carm Morales

"We travel not to go anywhere, but to just go.  We travel for travel's sake.  Our great desire is to move."

Re: 1992 Onan diesel no crank

Reply #6 –
Quote from: Yurre –
They are 12 volt.  Three of the large one.  Like I told Mike, they crank the Detroit
no problem.
It's definitely a Gen. problem.  Hopefully nothing major.
Thanks,
Occam's Razor again.  Just for the fun of it, run along the battery cable from the battery post to the first junction.  Once there check that all connections are clean and tight.

I've always had the gasoline/propane Onans and on those I've had trouble with the battery connection at the generator.  But yours is different.  Quieter and uses less fuel.
1992 Foretravel Grand Villa
U225 SBID Build No. 4134
1986 Rockwood Driftwood
1968 S.I.A.T.A. Spring
1962 Studebaker Lark
1986 Honda VF700C
1983 Honda VF750C
Charlie, the Dog was broken out of jail 24 Oct 2023
N1RPN
AA1OH (H)e who must be obeyed.

Re: 1992 Onan diesel no crank

Reply #7 –
Agree, check voltage AT THE GENERATOR when cranking. that will tell you if there is a voltage issue where it is important-- at the generator. BTW, if an issue, equal chance it is on the ground/negative side.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: 1992 Onan diesel no crank

Reply #8 –
Quote from: wolfe10 –
Agree, check voltage AT THE GENERATOR when cranking. that will tell you if there is a voltage issue where it is important-- at the generator. BTW, if an issue, equal chance it is on the ground/negative side.
It does not crank over at all.  When using the switch on the Gen. it makes a buzz and then
flips the control switch!  (one of the two off/on switches on the control panel.)
1992 Silver U300 40
DD 6V92 Allison
95K miles

Re: 1992 Onan diesel no crank

Reply #9 –
Quote from: Yurre –
It does not crank over at all.  When using the switch on the Gen. it makes a buzz and then
flips the control switch!  (one of the two off/on switches on the control panel.)
Sounds like a bad starter to me.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: 1992 Onan diesel no crank

Reply #10 –
Right, I'll check the solenoid first.  I wonder if the starter is accessible without
removing the gen?  It looks pretty tight in there.
1992 Silver U300 40
DD 6V92 Allison
95K miles

Re: 1992 Onan diesel no crank

Reply #11 –
I believe that our generators were installed using General Motors installation theory, which requires you to disassemble the vehicle starting with the gas cap. <grin>

Yes, the starter is on the back side as you look at the generator. If you slide the generator out you may be able to get to it.

I'm curious, though, about the sequence of events. You were using the generator, then disconnected the batteries to charge them, and then the generator wouldn't start. Is that correct? Do you have two sets of batteries? Our 1993 U300 has three normal-size batteries in the engine area that start the engine and run the automotive side of the coach. Two 8D batteries, located in a small bay just forward of the left rear tires, runs the house and the generator. Those batteries are designed so that all of the connections are at one end, just by the bay door. You should be able to put a meter on those terminals and see what each battery says.