Onan 5500. Soooo...... We camped this past weekend at the local lake/state park. Had an awesome time! On the way there, as I always do, I ran the generator so I could run the house A/Cs and to exercise the genset. When it was time to leave, I unplugged the shore line, and noticed that the slide was abnormally slow coming in on the house battery alone. Went outside to crank the geset, and it would only give a loud click and then smaller clicking like the battery was too weak to turn it over. I figure the house battery is dead or going dead. We head home, and when I get home, I replaced the house battery (I was using a single 12VDC combination battery) with 2 6VDC Trojan Golf Cart batteries. Genset still clicks loudly and then little clicks like the battery is still too weak....but I know it's not....testing the new batteries when trying to crank the genset shows only a slight voltage drop from 13.6 to 12.8.Things I've checked already...... battery cables...good connection. Genset engine oil... good and recently changed at the beginning of the season. Ran out of daylight before I could get any further....And.......GO!

Have you tried "jump starting" the generator direct? A voltage drop does not really show how much current is getting to the generator starter. Have you checked the power cables at the generator itself?

rgatijnet1 wrote:Have you tried "jump starting" the generator direct? A voltage drop does not really show how much current is getting to the generator starter. Have you checked the power cables at the generator itself?Next on my list.....ran out of daylight last night.

My RV has a switch on the wall next to the house battery that turns on the connection to the house battery. Without that switch on I get the same results as you. If that's on I would have a local auto parts store check the battery since they will do it for free. That would point the finger in the right direction at least.

Juzaxadar wrote:My RV has a switch on the wall next to the house battery that turns on the connection to the house battery. Without that switch on I get the same results as you. If that's on I would have a local auto parts store check the battery since they will do it for free. That would point the finger in the right direction at least.Thanks for the suggestion, but my battery disconnect switches for both chassis and house are in the engine bay. There is no "Salesman Switch." Batteries are brand new and show good voltage.....2 Trojan 6VDC Golf Cart batteries. Converter is putting out 13.8VDC, and I get 13.8 at the DC panel inside. I haven't checked the actual battery cable connections at the genset itself. The cables at the new house batteries are good and clean and tight.I can hear the starter solenoid click, and then the fuel pump clicking, just no engine turn-over. Until this last attempt at the state park, it's started and run perfectly.

Just because voltage is good does not mean enough amps are getting through to turn over starter. I had this same issue several years back, good voltage, cleaned all connections but all I got was the clicking sound. I finally traced the cable from the genset to the house batteries and found the cable inside the terminal was slightly green even though the outside was clean and tight. When I wiggled the cable it was also slightly loose. After cleaning the cable end and terminal I soldered and crimped the cable end and 10 years later all is still well.

Generator Won't Turn Over | Good Sam Community

tropical36
Explorer
Aug 12, 2018
10forty2 wrote:
Problem solved. Pulled the generator, replaced starter, hit the switch, and BAM! Started right up. I must say, pulling the generator wasn't as bad as I had anticipated, but it definitely took two people and a couple of bottle jacks. Not sure WHY any RV manufacturer wouldn't put those things on a slideout tray..... I guess they planned on getting the repairs themselves.....

EDIT to say, that after following all the diagnostic steps outlined by everyone here, I traced it to the starter. New batteries, all cables were cleaned and tightened, solenoid jumped and 12vdc applied directly to the starter via jumper cables....all did nothing. Measured the voltage before and after pushing the start button...not drain on the batteries, which indicated the starter was not pulling any current. Sooo, the only thing left was to replace the starter. Replaced it with Onan OEM....didn't like reviews of any of the aftermarket starters. More pricey than I wanted but found it on ASAP Parts online. Good website for Onan generator parts....

ASAP Parts for Techs

On an old 87 Pace Arrow we once had, I was able to remove the starter from below, repair it and reinstall it on the morning we were set to leave. Only held us up for a few hours and we were underway, after lunch. Not so sure about the last one we had with a Generac, as I did have to drop it, using a floor jack and homemade platform to replace the Stator.
Now with our present quiet diesel, it had to be dropped, just for replacing the water temp. sensor, so.............
10forty2
Explorer
Aug 12, 2018
Problem solved. Pulled the generator, replaced starter, hit the switch, and BAM! Started right up. I must say, pulling the generator wasn't as bad as I had anticipated, but it definitely took two people and a couple of bottle jacks. Not sure WHY any RV manufacturer wouldn't put those things on a slideout tray..... I guess they planned on getting the repairs themselves.....

EDIT to say, that after following all the diagnostic steps outlined by everyone here, I traced it to the starter. New batteries, all cables were cleaned and tightened, solenoid jumped and 12vdc applied directly to the starter via jumper cables....all did nothing. Measured the voltage before and after pushing the start button...not drain on the batteries, which indicated the starter was not pulling any current. Sooo, the only thing left was to replace the starter. Replaced it with Onan OEM....didn't like reviews of any of the aftermarket starters. More pricey than I wanted but found it on ASAP Parts online. Good website for Onan generator parts....

ASAP Parts for Techs
bjbear
Explorer
Aug 04, 2018
10forty2 wrote:
Looks like I'm going to have to pull the generator to replace the starter. I can manually turn the engine and it turns freely. The starter solenoid seems to be working good, and the voltage is getting there, but all that happens when I hit the button is the solenoid "CLICK" and the fuel pump running.....but not turning the engine. Gotta plan another day with a couple friends, some bottle jacks, and boards to slide the genset out so I can get to teh starter to replace it. Guess that'll be a good time to do all the other servicing too.....

Before pulling the generator, I would recommend that you connect a voltmeter to the studs on the 12V supply on the generator itself. Try to attach to the end of the threaded section and not to the cable itself.

Step 1 - Then take a reading. Should be same as batteries.

Step 2 - Then have someone attempt to start the generator and observe the voltage reading. You may find that the voltage droops very low (i.e. < 9 volts).

If voltage is less than battery volts in step 1, check your ground cable
If voltage drops low in step 2, it means you probably have a bad/dirty connection on the 12 V cable(s). If voltage does not drop in step 2, then it is probably a bad starter or solenoid.

Note... a low voltage on step 2 could be the starter/solenoid, but a bad connection is more likely so should be checked before removing/working on generator.
10forty2
Explorer
Aug 04, 2018
Looks like I'm going to have to pull the generator to replace the starter. I can manually turn the engine and it turns freely. The starter solenoid seems to be working good, and the voltage is getting there, but all that happens when I hit the button is the solenoid "CLICK" and the fuel pump running.....but not turning the engine. Gotta plan another day with a couple friends, some bottle jacks, and boards to slide the genset out so I can get to teh starter to replace it. Guess that'll be a good time to do all the other servicing too.....
10forty2
Explorer
Jul 27, 2018
old guy wrote:
one thing many people over look is even if the cable ends are clean and tight there might be enough corrosion inside the cable under the protective cover. it happened to me and I was dead in the water. had to be towed in and the mechanic was smart enough to find the problem

That's something I haven't checked, but will put it on the list once I get some time to get back into it! Thanks!
10forty2
Explorer
Jul 27, 2018
wa8yxm wrote:
That ALMOST happened to me... Thankfully I caught the problem before it happened.

The Slow retraction was due to low battery power. This may be due to batteries at end of age or .. Read my story.

Might also be a tripped breaker in your breaker panel (CONV).

The story... Last October (29th) I came home from Church and noticed things were not right.. Very low voltage.. Seems my veneraboe old duodecade (12 years) old Progressive Dynamics 9180 had bit the dust... So Being sunday it was off to Auto Zone for a Deltran Battery Tender.. This is the big one. 70 amp jump start (no use in this case) 20 amp Bulk and 1-2 amp tender. Set it to 20 amps and 24 hours later it dropped to tender. I was packed so I pulled the slides in and off we went.

TO Marshall MI.. Where on Halloween I took my Debit card and the old 9180 and walked into the Progressive Dynanics Parts and Serivce department.

A short time later I walked out and it's been fine ever since.

All breakers and fuses are good. Converter is working and outputting 13.8vdc when plugged in to shore power.
10forty2
Explorer
Jul 27, 2018
bounder39zman wrote:
Either I missed it, or you failed to post model and spec number of your generator. If you post that info, you have a better chance of getting help and advice from people who have had similiar issues or are experienced in repairing these gensets

Onan 5500 BGM-FA/11578H
old_guy
Explorer
Jul 27, 2018
one thing many people over look is even if the cable ends are clean and tight there might be enough corrosion inside the cable under the protective cover. it happened to me and I was dead in the water. had to be towed in and the mechanic was smart enough to find the problem
wa8yxm
Explorer III
Jul 26, 2018
That ALMOST happened to me... Thankfully I caught the problem before it happened.

The Slow retraction was due to low battery power. This may be due to batteries at end of age or .. Read my story.

Might also be a tripped breaker in your breaker panel (CONV).

The story... Last October (29th) I came home from Church and noticed things were not right.. Very low voltage.. Seems my veneraboe old duodecade (12 years) old Progressive Dynamics 9180 had bit the dust... So Being sunday it was off to Auto Zone for a Deltran Battery Tender.. This is the big one. 70 amp jump start (no use in this case) 20 amp Bulk and 1-2 amp tender. Set it to 20 amps and 24 hours later it dropped to tender. I was packed so I pulled the slides in and off we went.

TO Marshall MI.. Where on Halloween I took my Debit card and the old 9180 and walked into the Progressive Dynanics Parts and Serivce department.

A short time later I walked out and it's been fine ever since.
bounder39zman
Explorer II
Jul 26, 2018
Either I missed it, or you failed to post model and spec number of your generator. If you post that info, you have a better chance of getting help and advice from people who have had similiar issues or are experienced in repairing these gensets

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