Generator

Grampy · 07-09-2021, 02:12 AM

Has anyone replaced the brushes in an Onan 3.6.

pneumatics · 07-09-2021, 07:47 PM

Years back I thought I could until I removed the cover. You just about have to disassemble the entire unit to get to the the brushes and I did not have the tools required. I removed the entire unit and took it to a Cummings Genset service shop and they did a great job.... replaced the carb also.

Grampy · 07-09-2021, 09:46 PM

Thank you, local shop wants $1200-1500 to find out if brushes or slip rings might be the problem. Seemed excessive. Wondered if I could do myself. Unit only has 66 hours.

tanman32225 · 07-09-2021, 10:11 PM

how many hours are the brushes good for? Mine is a 12k Onan

OldWEB · 07-09-2021, 11:12 PM

Is this part of the same problem you reported here? Have you tried any of the checks asked for in the Service Manual for yer unit? You seem to give minimal info on what you have found.

EDIT: So sorry, your original question asked if anyone has replaced the brushes. No, I have not. Manual states genny has to come out and the fan has to be removed to access them. Just wondering what diagnosis suspects the brushes.

**EA37TS** · 07-09-2021, 11:25 PM

Quote:

Originally Posted by Grampy

Thank you, local shop wants $1200-1500 to find out if brushes or slip rings might be the problem. Seemed excessive. Wondered if I could do myself. Unit only has 66 hours.

How old is the unit.

Discussed at length during the Onan seminar yesterday. Old units with low hours are junk due to lack of use. A 2 year old gen with 5000 hours is better than a 3 year old unit with 200 hours. Generators have to be run.

dkoldman · 07-10-2021, 12:21 AM

Quote:

Originally Posted by EA37TS

How old is the unit.

Discussed at length during the Onan seminar yesterday. Old units with low hours are junk due to lack of use. A 2 year old gen with 5000 hours is better than a 3 year old unit with 200 hours. Generators have to be run.

Preach brother

I had to argue with a Pro Lithium Enthusiast why when boondocking; 24 hrs capacity from my batteries to serve all of my Inverter loads with normal usage was all I needed because regardless of how much I use or don't use. My genset will come on for 2 hours every day and top me back off at full. Somehow he didn't view the 2 hrs per day exercise of genset a good thing

Even with that, I still can't run my genset anywhere near that 150hrs/yr but I sure try

OldWEB · 07-10-2021, 12:33 AM

Quote:

Originally Posted by EA37TS

How old is the unit.

Discussed at length during the Onan seminar yesterday. Old units with low hours are junk due to lack of use. A 2 year old gen with 5000 hours is better than a 3 year old unit with 200 hours. Generators have to be run.

Oh wow... you got ME worried now. Our generator has 20 hrs and is going on 12 years old! This coming week I will be boondocking, so it will be run for sure! Thanks for the heads up.

Scubawise · 07-10-2021, 12:53 AM

Thanks all experts we dry camp at state parks and will continue to use the generator

dkoldman · 07-10-2021, 01:15 AM

Quote:

Originally Posted by OldWEB

Oh wow... you got ME worried now. Our generator has 20 hrs and is going on 12 years old! This coming week I will be boondocking, so it will be run for sure! Thanks for the heads up.

To hammer EA37TS point?

Onan extended the warranty on my unit simply because I had Onan Authorized Dealer install the EC-30 AGS to go with my Onan 5500. They stated that Onan generators where customers have installed the EC-30 AGS are the most trouble free. Presumably if you invest in one you will use more so than the guy that had it come with the coach; but never took the time to use.

The EC-30 is by far my favorite toy in the RV. I use every feature documented

My genny will fire up if there is a shorepower loss, gets too hot in the coach (over 78), or if my house batteries drops below 12.5vdc.
It also tops off my batteries everyday when boondocking 2 hours before Quiet time. My quiet time is 12 hours 8:00 PM to 8:00 AM next morning

Grampy · 07-10-2021, 05:50 AM

Quote:

Originally Posted by OldWEB

Is this part of the same problem you reported here? Have you tried any of the checks asked for in the Service Manual for yer unit? You seem to give minimal info on what you have found.

EDIT: So sorry, your original question asked if anyone has replaced the brushes. No, I have not. Manual states genny has to come out and the fan has to be removed to access them. Just wondering what diagnosis suspects the brushes.

Thank you, after troubleshooting many things ourselves we determined it was probably the control board. So took it to Cummins shop to troubleshoot. They said control board could be going bad. Also used ohm meter and found too much resistance somewhere. They think brushes are stuck or dirty slip rings. But says $1200-1500 to check either.

OldWEB · 07-10-2021, 10:58 AM

Quote:

Originally Posted by Grampy

Thank you, after troubleshooting many things ourselves we determined it was probably the control board. So took it to Cummins shop to troubleshoot. They said control board could be going bad. Also used ohm meter and found too much resistance somewhere. They think brushes are stuck or dirty slip rings. But says $1200-1500 to check either.

From a troubleshooting guide:

1) Tarnished slip rings from infrequent use - Check resistance on slip rings, clean if necessary.... Requires removal and some disassembly. Beyond capability of most owners. The voltage regulator will compensate for a poor connection through the slip rings until it fails. If your voltage regulator has failed, be sure the slip ring resistance has been checked - or it may fail again.

2) Failed voltage regulator - Replace voltage regulator.... Requires removal of generator. The Onan voltage regulator is expensive, not repairable and has no warranty. Check for causes of failure to avoid failure of the new part. This testing beyond the capability of most owners

Good Luck!

The Gritz Carlton · 07-10-2021, 03:54 PM

"Cocktails in the Camper" once a week will keep the generator alive. Crank it, run the A/C(s) and drag the queen out there. There's multiple benefits hidden here.

Grampy · 07-10-2021, 08:45 PM

Quote:

Originally Posted by EA37TS

How old is the unit.

Discussed at length during the Onan seminar yesterday. Old units with low hours are junk due to lack of use. A 2 year old gen with 5000 hours is better than a 3 year old unit with 200 hours. Generators have to be run.

2013 with 66 hours

Grampy · 07-10-2021, 08:49 PM

Quote:

Originally Posted by The Gritz Carlton

"Cocktails in the Camper" once a week will keep the generator alive. Crank it, run the A/C(s) and drag the queen out there. There's multiple benefits hidden here.

Sounds good to me. Thanks for the advice.

dkoldman · 07-10-2021, 11:38 PM

Quote:

Originally Posted by Grampy

2013 with 66 hours

Have you had it the entire time or did you buy it like that with low hours.

I am curious because you never said; but what is it doing or not doing; and when did it start or stop?

That genset avg 8 hrs / year. I am only averaging 75 hrs per year and I am trying very hard to double that

It is easier said than done. When you do get it fixed; things to make the Genny easier to use besides the romantic escapes

1. Buy or use the AGS, let it work for you and keep things going. I have never had to prime my genset because it runs so frequently.
2. When it has started, let it run at least 10 minutes before shutting down
3. Don't hesitate to turn on to use ACs if coach is warm, I can't tell the difference in gas cost. I know it is a little more, but I can't measure any relevant amount.
4. Put in Quiet Time mode at home and even on some trips when boondocking, you will get at least 2 hrs / day.
5. Changing my own oil and filter also tends to make me want to use it after I have dome the work servicing it

Good luck

Grampy · 07-11-2021, 03:37 PM

Quote:

Originally Posted by dkoldman

Have you had it the entire time or did you buy it like that with low hours.

I am curious because you never said; but what is it doing or not doing; and when did it start or stop?

That genset avg 8 hrs / year. I am only averaging 75 hrs per year and I am trying very hard to double that

It is easier said than done. When you do get it fixed; things to make the Genny easier to use besides the romantic escapes

1. Buy or use the AGS, let it work for you and keep things going. I have never had to prime my genset because it runs so frequently.
2. When it has started, let it run at least 10 minutes before shutting down
3. Don't hesitate to turn on to use ACs if coach is warm, I can't tell the difference in gas cost. I know it is a little more, but I can't measure any relevant amount.
4. Put in Quiet Time mode at home and even on some trips when boondocking, you will get at least 2 hrs / day.
5. Changing my own oil and filter also tends to make me want to use it after I have dome the work servicing it

Good luck

Thank you for this info. We just bought the motorhome. It is a 2013 with 22,000 miles. So not used much at all. My issue is it will start right up but dies when I let off the start button. If I hold the button in it will shut off on its own in about 15 seconds. It doesn’t just die, it shuts spark off to spark plug.

OldWEB · 07-11-2021, 04:50 PM

Quote:

Originally Posted by Grampy

Thank you for this info. We just bought the motorhome. It is a 2013 with 22,000 miles. So not used much at all. My issue is it will start right up but dies when I let off the start button. If I hold the button in it will shut off on its own in about 15 seconds. It doesn’t just die, it shuts spark off to spark plug.

Can you check if there is any voltage generated when it does run? If none, then either the slip rings are not letting the power into the generator or the control board is not send any power to the slip rings.

Search the 'net for a Service Manual for your Unit and it will give some checks to do. Same ones I would think the service center did.
Good Luck!

Grampy · 07-11-2021, 05:12 PM

Quote:

Originally Posted by OldWEB

Can you check if there is any voltage generated when it does run? If none, then either the slip rings are not letting the power into the generator or the control board is not send any power to the slip rings.

Search the 'net for a Service Manual for your Unit and it will give some checks to do. Same ones I would think the service center did.
Good Luck!

Cummins had their best tech trouble shoot. Says it’s pulling too much resistance. They say either dirty slip rings or brushes not making good contact. But want $1200-1500 to check those out. So was want input as to whether I could do that myself or not.

dkoldman · 07-11-2021, 05:27 PM

Quote:

Originally Posted by Grampy

Cummins had their best tech trouble shoot. Says it’s pulling too much resistance. They say either dirty slip rings or brushes not making good contact. But want $1200-1500 to check those out. So was want input as to whether I could do that myself or not.

For me it would not even be an option. But from what I have read on your plight, your situation and your expertise; I would deal only with Cummins which you are appearing to be doing. I would commit to get it working and maybe with some Cummins warranty. Ask about adding the new AGS and maybe they work with on cost. They may align the warranty for generator with AGS? Since coach is new to you and if Cummins can recertify the genset, it will be like a brand new genset so all you got to do is just use it so it does not happen again. I would put a cap at $2,500 in total before considering replacing with a new one.

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