Jump to content
rwitt

Onan 10KW Gen Hard To Start

Recommended Posts

I have a Onan 10KW gen.  It has been starting immediately until yesterday. Tried to start it from inside and it would not start. Went to gen and tried starting from there.  I could hear it clicking but not even trying to start.  After several tries with just clicking all of a sudden it started. Later in the evening we lost power and gen was set to come on but it didn't start.  I have just over a half tank of diesel and filters were changed in May.  

Any ideas where to start?  

Panel shows floating charge DC 13.4V

Share this post


Link to post
Share on other sites

I would start by checking and cleaning all 12 v cables and grounds to the generator.Could be something else such as a bad selenoid, but first things first, ground cables are usually bolted to the chassis, and with dissimilar metals, oxidation can occur causing conditions like you are describing.

Share this post


Link to post
Share on other sites
36 minutes ago, rwitt said:

I have a Onan 10KW gen.  It has been starting immediately until yesterday. Tried to start it from inside and it would not start. Went to gen and tried starting from there.  I could hear it clicking but not even trying to start.  After several tries with just clicking all of a sudden it started. Later in the evening we lost power and gen was set to come on but it didn't start.  I have just over a half tank of diesel and filters were changed in May.  Any ideas where to start?  Panel shows floating charge DC 13.4V

The Onan diesel generators can be primed by holding the start switch in the stop position for 30 to 45 seconds, then retry the start position. If it starts you might have a fuel supply line or fuel pump problem starting to show up. Fuel possibly draining back to the tank do to a compromised supply line.

Kay, did mention cleaning the 12 volt connections, but you did not say that the engine was turning over slowly. There is a fuse under the circuit breaker cover that might be blown. This fuse is for the glow plug power feed. If you get it started and warmed up - stop the generator. Try letting it set for 15 to 20 min. If it starts right up that could indicate a glow plug issue. The oil level being low is  also a possible issue ?

You did not mention the year of your coach or how many Hrs. on the generator.

Note, in a resent conversation with Cummins power, they mentioned that there has been an issue with the fuel pump. I regret to say that I forgot to ask if there was a particular production run or if the pump problem was related to the change to ULSD that affected the chassis engines.

Rich.

Share this post


Link to post
Share on other sites

Ron,

Just to confirm:

You can hear the fuel pump clicking.

But, the engine does not even try to turn over? OR it turns over slowly? OR it turns over at normal speed, but does not start?

Share this post


Link to post
Share on other sites

I can hear what I think is fuel pump clicking but gen not turning at all.  I did the priming and then held start side down. It continued to click for about 15 sec and then started.  Is there a separate fuel pump for the gen?  Does gen start off house batteries?  Could it be some dirty fuel and would some Seafoam cleaner help?  

2008 Monaco. Onan Quiet Diesel 10KW with 1335 hrs

TIA

Ron

Share this post


Link to post
Share on other sites

Ron,

Yes, you have a separate electric fuel pump-- that is the clicking you hear.

Most, not all coaches are wired to start the generator from the house batteries.

My suggestion is to have someone else attempt to start it while you use your digital voltmeter to check voltage on the large-gauge 12 VDC wires going into the generator. Reading should be same as house bank.  Then when the other person attempts to start it, verify that voltage does not drop below 12 VDC.  If it does, do the same check at the battery.  If voltage at the battery drops significantly, batteries are bad.  If it doesn't drop significantly at the batteries, but does at the generator, start by cleaning and tightening connections at generator and at battery.  Be sure to do the generator ground as well.

Share this post


Link to post
Share on other sites

Actually could be a battery issue.  The Float Charge reading of 13.4v may be reading the output of your charger.

We had similar issue a few years back.  Does pushing the engine battery assist switch and generator start switch work for you?  I seem to remember doing that but it's been a few years and beers ago.

Blake

Share this post


Link to post
Share on other sites

Update:  I tried to get it started the same way I did yesterday and it would not start.  I finally figured out that it was giving me a code 32 so after looking that up I proceeded to check grounds and all terminal connections on the batteries and at the generator.  It seemed that some of the connections were possibly a slight bit loose.  I cleaned both connections to the gen.  I then tried to start it.  It didn't start right up so I primed it again for about 5 sec and it started.

Mama is washing right now so when she's done I'm going to try to cut shore power and see if the auto start works.

My meter reading at the gen while trying to start it the first time today went to 12.3.  I'm thinking I may still have a issue with batteries.  Probably will replace all of them since I don't know how old they are.  No indications to when they were installed.

I'll post the results of the auto start test later.  Thanks for everyone's help.

Ron

Share this post


Link to post
Share on other sites

If the reading at the generator never dropped below 12VDC while you were trying to start the genny (this is the critical time) then your batteries are likely OK.  Assuming you mean the reading "went to 12.3" from something like 13.2 (float) then your batteries are good.

Share this post


Link to post
Share on other sites

Yup, not dropping below 12 VDC when trying to start the generator, removes then as a "prime suspect" of your no-start issue.  But with the starter not working (no high amp draw), you have not really tested the batteries.

But totally agree with Bill, look elsewhere for why the starter is not engaging.

Share this post


Link to post
Share on other sites

Just completed the auto start test.  It failed.  Apparently it tries a couple of times and only about 10 secs each time.   (could hear the pump clicking}.  then it set the same code 32 and it doesn't try again.  I tried to prime and start from the remote switches inside and then on the gen and it still wouldn't start.  Next I started the coach and let it run a few minutes.  Tried same sequence and nothing.  Waited a few mins again and then tried from remote switch and pressed the bat assist.  after about 30 secs it started.,,,,,,,,,,,,,,,,,,

Does this give anyone any ideas?

It's starting to get hot country again (been up in NW)  We have two dogs so really trying to get the auto start working so we can leave them.

Ron

Share this post


Link to post
Share on other sites

With the coach engine running and at fast idle does it start right up? If not with the same condition pushing the battery combine switch will it start right up? Code 32 seems to indicate that the stater does not start turning when power has been applied to the control board on most Onan generators, you did not give model number of yours. Can the 12 volt cables be removed from the coach source and a fresh 12V battery hooked directly to the genset, then try starting. If this does not work correctly, I would look for a Cummings/Onan repair facility.

Share this post


Link to post
Share on other sites

It started up after I pushed the battery assist and held start down for about 5 to 10 secs

 

Share this post


Link to post
Share on other sites
1 hour ago, rwitt said:

Just completed the auto start test.  It failed.  Apparently it tries a couple of times and only about 10 secs each time.   (could hear the pump clicking}.  then it set the same code 32 and it doesn't try again.  I tried to prime and start from the remote switches inside and then on the gen and it still wouldn't start.  Next I started the coach and let it run a few minutes.  Tried same sequence and nothing.  Waited a few mins again and then tried from remote switch and pressed the bat assist.  after about 30 secs it started.,,,,,,,,,,,,,,,,,,

Does this give anyone any ideas?

It's starting to get hot country again (been up in NW)  We have two dogs so really trying to get the auto start working so we can leave them.

Ron

Hi Ron, If you have cleaned all the battery cables and other connections. Look closely at all the cables as I had one that was damaged but it was hidden from view. If you have done this and still not geting adequate amperage, I have to conclude you have a battery problem. I would guess the generator ties into the house batteries. Should be easy to test just take the ground off the house batteries and see if it starts/cranks. 

Bill

Share this post


Link to post
Share on other sites

Well, 4 new batteries and generator starts right up.  Thanks to everyone for the help.  All of you are great.

Ron

Share this post


Link to post
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now

×
×
  • Create New...