Generator exercise

[Bud]

"They've told me that essentially you just can't wear one out."

That is my understanding concerning the Engine, and I have written just that.

"Failures occur primarily because of fuel system issues that manifest from non-use"

With a gasoline carb, yes you can't leave the gas to dry out. All? agree.

"And again, if they recommend the two-hour/month exercise regimen to prevent fuel system and whatever else fails, what's the big deal about running it for two hours/month?"

Same question, you can't think of any downside to running a generator 3-4 time longer?

Bud

[hepcat]

Originally Posted by Bud

Same question, you can't think of any downside to running a generator 3-4 time longer?

Bud

According to the techs I've had the experience chatting with no, there's apparently no downside to using the generator as much as you want, as long it gets the requisite 2hrs/continuous time at half-load once a month. I've been told that there are Onan generators in remote, off-grid residential service with thousands of hours on them that have required only routine service-interval maintenance.

[Bud]

"According to the techs I've had the experience chatting with no, there's apparently no downside to using the generator as much as you want"

So I can use the onan to power something or exercise it with no penalty for exercise vs powering something. Exercise is Free, no cost, no penalty, no expense, no nothing, no downside to exercise.

Bud

[GallenH]

I see. Makes sense. I suppose you could do it if you wanted to haul around extra LP but who does? It does seem "trade-offish" though. I'm continually reading about problems with them. Don't have one myself. Thanks

[hepcat]

Originally Posted by Bud

"According to the techs I've had the experience chatting with no, there's apparently no downside to using the generator as much as you want"

So I can use the onan to power something or exercise it with no penalty for exercise vs powering something. Exercise is Free, no cost, no penalty, no expense, no nothing, no downside to exercise.

Bud

Bud, apparently that is the case. The only cost is fuel... and the upside is generator reliability. And it's their opinion that the coach chassis will be scrapped long before the generator fails from being "worn out."

And again, I have no data with which to back those claims up... I'm merely parroting what I've been told by the guys who work on them daily. Since they've revived two 2800s for me now, one gasoline and one LP, I have no reason to disbelieve them.

[hepcat]

Originally Posted by GallenH

I see. Makes sense. I suppose you could do it if you wanted to haul around extra LP but who does? It does seem "trade-offish" though. I'm continually reading about problems with them. Don't have one myself. Thanks

The only problem that my LP 2800 has had was mud daubers clogging the vent on the generator's LP regulator, apparently a common problem. It appears that one must just be a little more judicious about planning for your LP use and refills.

[@Michael]

Originally Posted by avanti

Any evidence-based responses that contradict these opinions are heartily welcome.

I have a lot of experience with small gasoline engines since learning to repair lawn mower and chain saw engines 45+ years ago. It is with great reluctance that I join this thread.

On some ICE's I have been able to ignore all the rules, leave the gas in for years, and they still start and run. I left the same gas in a carbureted Porsche for 5 years and when I finally started it, it ran (rough, barely, until I shot carb cleaner in all the needles and jets).

But my brand new Onan, after sitting on the dealer lot for about 6 months, did not run at the time I picked up the RV. The dealer offered to delay delivery and take it to Onan. Instead I took it home, betting that it was a gummed up carb that would either clear itself or would be an easy fix in my driveway. It took about a few start attempts and 20 minutes of barely running (lean surging) before the carb cleared enough to run without surging and support a load. After an hour it was fine.

Since then, if I leave it sit a few months without running, I get a minute or two of lean surging 'till it clears. For me, for this Onan, running it every month or so seems to be necessary to avoid carburation issues. Whether or not that needs to be 2 full hours at load, I'm not sure. It needs to run though - long enough to drive off any moisture and clear the carb.

I suspect that the Onan's are more sensitive to fuel issues than some engines, and hence will roughly follow the Onan manual.

[booster]

Although this has all been gone over before, and this thread is just a rehash for other reasons, IMO, I will point out that if talking about the fuel issue in gas Onans, the type of gas is a huge issue based on what we found.


When we had our Onan, which was the newer small passage style from about 10-12 years ago, I did repeated tests with 10% ethanol fuel with and without Seafoam, and pure gas with and without Seafoam. I had setup our van with a switchable feed port so it could be run from gas cans.



We would get surging under load, or killing on AC compressor start, after 3-5 weeks on the 10% ethanol gas. I let it sit as long a 3 months on pure gas and it was still fine at restart when I ended the tests. Both types of fuel would make it a full 5-6 months over the winter with Seafoam laced gas in them. I never tested running it dry, but I would certainly think that would work also, as I did that when I removed our Onan and it sat for over a year and then it started and ran fine.


This all goes back to the original premise that has been oft repeated, and that is conditions are probably the most important thing to consider in how often to exercise the Onan.



The Onan requirements appears to be setup to be what is needed for a small passage gas unit on 10% ethanol gas without any preservative in it. If you have other than that, like a propane unit, pure gas, or make sure there is preserved gas, it is very likely you could increase the interval time or reduce the run time.



For the corrosion issue on all models, atmospheric conditions appear to be the biggest influencer of frequency of running, and from what saw the need is less frequent than the worst case fuel intervals. Of course, it it is sitting by the beach with salty air or parked in a snowbank for months you will likely be on a much shorter interval than in a condition controlled storage area.


Everyone needs to look at the information and experiences that have given in all the discussions of this topic and decide for themselves what is right for them based on their model, fuel, conditions and risk tolerance, and that is why, IMO, the whole premise of this thread to push everyone into the same Onan spec mindset while demeaning those who suggest otherwise is misplaced.


Sidebar the wear it out statements by exercising. From what I was able to find out searching and what the Onan development guy told me (long story how he just showed up at my house) the engine and generator are typical 2500 hour rated units. To me that means they could easily last 50% more or 50% less than that and be within range. Once a month for two hours will put 24 hours a year on it or 240 hours per decade. It would appear to me that unless you use it a lot of other hours you would not likely ever wear it out, but then it also would not need the exercising because used regularly. Will it be more likely to need repair or more periodic preventative at higher hours, probably, but could also be the same or better depending on conditions. There does appear to be support for both sides of this part of the discussion.

[Bud]

Hi booster,

You talked about 2 issues, one factual and the other one speculative.

Factual, we know what happens with the tiny jets get varnished up, clogged.

Speculative, how long to exercise the onan. "the engine and generator are typical 2500 hour rated units" I don't doubt that one could maintain an onan 2800/2500 indefinitely, but so what?

The question is first, why do onan 2800/2500 fail and have to be removed from the van? It seems to me over many years of reading about onan failures on class b forums, whether an onan was exercised or not was rarely involved, not even a part of the subsequent discussion. If that is true, 3-4 times more exercise time adds up to more failures and multiple failures.

Someone could spend a heck of lot of time reading about onan 2800/2500 failures and they categorize them by cause, etc.

booster, what is your own recollection of onan failures and were they exercise related?

Bud

[booster]

Originally Posted by Bud

Hi booster,

You talked about 2 issues, one factual and the other one speculative.

Factual, we know what happens with the tiny jets get varnished up, clogged.

Speculative, how long to exercise the onan. "the engine and generator are typical 2500 hour rated units" I don't doubt that one could maintain an onan 2800/2500 indefinitely, but so what?

The question is first, why do onan 2800/2500 fail and have to be removed from the van? It seems to me over many years of reading about onan failures on class b forums, whether an onan was exercised or not was rarely involved, not even a part of the subsequent discussion. If that is true, 3-4 times more exercise time adds up to more failures and multiple failures.

Someone could spend a heck of lot of time reading about onan 2800/2500 failures and they categorize them by cause, etc.

booster, what is your own recollection of onan failures and were they exercise related?

Bud

Of the Onan problems I have seen over the years, either in person or from all the reading of issues, I would have to guess that most (75%?) were for either plugged up carbs or corroded slip rings split very heavily to the carbs. Those would both be exercise related in most cases, I think.


Next would be fuel pump, then control boards, plus a oil level sensors making up most of the rest and those would not be exercise related. There have been only a few actual engine related issues that I have seen, and one of them was caused by Onan for nearly certain as the valvetrain destroyed itself right after an Onan scheduled service which included valve adjustment. Same for actual armature replacements, which are hard to tell if they were because of basic failure or because it got too corroded to be able to polish back.


As always in this stuff, we only here about the ones that have trouble so hard to tell how many have made 2000+ hours, or how many could put up with the noise for that long . I have seen van for sale ads on a couple that were over 1000, though, and I think many didn't even have meters on them? You see well over 2500 hours on the bigger ones all the time in ads.

[Bud]

Originally Posted by booster

Of the Onan problems I have seen over the years, either in person or from all the reading of issues, I would have to guess that most (75%?) were for either plugged up carbs or corroded slip rings split very heavily to the carbs. Those would both be exercise related in most cases, I think.


Next would be fuel pump, then control boards, plus a oil level sensors making up most of the rest and those would not be exercise related. There have been only a few actual engine related issues that I have seen, and one of them was caused by Onan for nearly certain as the valvetrain destroyed itself right after an Onan scheduled service which included valve adjustment. Same for actual armature replacements, which are hard to tell if they were because of basic failure or because it got too corroded to be able to polish back.


As always in this stuff, we only here about the ones that have trouble so hard to tell how many have made 2000+ hours, or how many could put up with the noise for that long . I have seen van for sale ads on a couple that were over 1000, though, and I think many didn't even have meters on them? You see well over 2500 hours on the bigger ones all the time in ads.

Thanks booster. For the moment, I'll go with your 75% although it seems high maybe. If 75%, how many are carbs? Those are almost always a Lack Of exercise and not how long, so I don't count those. I would guess of the 75% most are carb which again is not a question of how long to exercise. That means most failures are not exercise related, rather just plain running the onan.

No one can prove their onan is happy because they exercised for 2 hours. Yet there are Many bud's, avanti's ................ that don't do 2 hours with happy onans. And the 2 hour folks, lots of them, with onan failures and multiple failures.

Bud

[EnduroRdr]

It’s been almost an hour since the last poke! Come on guys, don’t stop now! I know you still have plenty of good insults to sling around!
“ my generator maintenance is better than yours “ lol.

Ok maybe you guys need some new material to argue over?

Here’s a topic:

I prefer gas over propane because of available run time. (And economy).
My previous WGO ERA would only run about 28-30 hours on a tank of propane. Granted it had a smallish tank (I forget may 8 gal???).
I live in deep south and often boondock, so I absolutely need a/c on nights between April and October.

My issue was to refill the “onboard” propane, you are limited to the places that can fill your tank.

My current rv is on promaster chassis with a 2800 gas stuffed under it, but it pulls fuel from the promaster tank.
Therefore I can re-fuel at any convenience store.

So let’s hear which type generator is better?

Ok men take sides and commence the dueling!

[Davydd]

A company that requires an ICE engine to be run 2 hours every month must manufacture a really crappy product. I long ago chose not to go that route and have no generator with my current Sprinter. When I did have propane generators I ignored those recommendations for 9 years and they started every time.

[booster]

Originally Posted by Bud

Thanks booster. For the moment, I'll go with your 75% although it seems high maybe. If 75%, how many are carbs? Those are almost always a Lack Of exercise and not how long, so I don't count those. I would guess of the 75% most are carb which again is not a question of how long to exercise. That means most failures are not exercise related, rather just plain running the onan.

No one can prove their onan is happy because they exercised for 2 hours. Yet there are Many bud's, avanti's ................ that don't do 2 hours with happy onans. And the 2 hour folks, lots of them, with onan failures and multiple failures.

Bud

Bud, how did you get that most are not caused by lack of exercise from what I said? Of course you have to count the plugged carbs. You can make a good argument for using less than the two hours, for sure, but not the frequency, and again only under certain circumstances is the short frequency needed IMO. I can tell you from our unit, which was clogged from day one, even though Onan had "cleaned" it for the dealer before delivery, that if you have to clean out a plugged carb, it works much better to run 20 minutes three times letting it sit overnight in between runs for Seafoam to work than it does to run it 60 minutes straight. This may apply to ethanol fuel also, but I really can't say. The killer with all this is if you have old ethanol fuel in the van tank, you just replace old fuel with different old fuel, and that is why we always put Seafoam in if it was going to sit any length of time and had ethanol fuel in it.

[Bud]

Originally Posted by booster

Bud, how did you get that most are not caused by lack of exercise from what I said? Of course you have to count the plugged carbs. You can make a good argument for using less than the two hours, for sure, but not the frequency, and again only under certain circumstances is the short frequency needed IMO. I can tell you from our unit, which was clogged from day one, even though Onan had "cleaned" it for the dealer before delivery, that if you have to clean out a plugged carb, it works much better to run 20 minutes three times letting it sit overnight in between runs for Seafoam to work than it does to run it 60 minutes straight. This may apply to ethanol fuel also, but I really can't say. The killer with all this is if you have old ethanol fuel in the van tank, you just replace old fuel with different old fuel, and that is why we always put Seafoam in if it was going to sit any length of time and had ethanol fuel in it.

Sorry booster, I probably did articulate it worth a darn.

Generally agree about carbs and consider it a FACT that leaving gas to dry out will result in a failure from a lack of exercise or not eliminating the fuel after running.

The speculative part is how long to run the onan, but you HAVE to solve the carb problem by exercise or no fuel in the carb jets. It is not a 'how long to exercise' thing.

Back to the speculative part, how long to exercise. If you eliminate carb failures since those are not a part of 'How Long to Exercise' that 75% you quoted which was carb failures and slip rings, that only leaves slip ring stuff which I'll bet is well less than half of the 75%, so > 37.5% plus 25% is over half of onan failures having nothing to do with 'how long to exercise'.

My guess is way over half of onan failures have nothing to do with 'how long to exercise'.

Bud

[GeorgeRa]

Both main issues Onan could solve by eliminating slip rings and by providing a remotely control valve to run it dry before storage for gas models or just eliminate slip rings for propane models, unfortunately this level of innovation could be at the level of rocket science for Onan folks.

I have on old Honda 1000W Inverter generator which I store dry, never had a problem with starts and, and, believe it or not, absolutely no corrosion on slip rings, and, it is very, very quiet.

Edit - instead of a valve a remote control of the fuel pump could allow to run the generator to dry before extended storage.

[hepcat]

Originally Posted by Bud

Back to the speculative part, how long to exercise. If you eliminate carb failures since those are not a part of 'How Long to Exercise' that 75% you quoted which was carb failures and slip rings, that only leaves slip ring stuff which I'll bet is well less than half of the 75%, so > 37.5% plus 25% is over half of onan failures having nothing to do with 'how long to exercise'.

My guess is way over half of onan failures have nothing to do with 'how long to exercise'.

Bud

Bud, as I said waaaay back in an earlier post, I'm pretty sure that the Onan recommendation is a one-size-fits-all proposal, and is aimed primarily at the fuel system issues. Failures from other sources such as circuit boards or sensors likely wouldn't be affected one way or the other by run time, either "exercise" or "use under load."

[moosey]

When we bought our 2000 RT V-200 two years ago, the previous owner had Onan install a new generator 2 years BEFORE we bought it. When we picked it up, the generator had less than 2 hrs on it. We thought that was great until we started looking through RV oriented web sites/forums, and found the info about exercising these things-under load, for at least 2 hrs a month. Obviously, the previous owner never did that. We drove it down to an Onan dealership in Portland (ME) and had them look it over...change the oil etc. They said it was running great and that we were probably lucky. The tech did recommend that we run it for a couple hrs a month under some kind of load. So...who knows. No exercising for two yrs preceding our purchase, and it was in fine condition.

[booster]

Originally Posted by moosey

When we bought our 2000 RT V-200 two years ago, the previous owner had Onan install a new generator 2 years BEFORE we bought it. When we picked it up, the generator had less than 2 hrs on it. We thought that was great until we started looking through RV oriented web sites/forums, and found the info about exercising these things-under load, for at least 2 hrs a month. Obviously, the previous owner never did that. We drove it down to an Onan dealership in Portland (ME) and had them look it over...change the oil etc. They said it was running great and that we were probably lucky. The tech did recommend that we run it for a couple hrs a month under some kind of load. So...who knows. No exercising for two yrs preceding our purchase, and it was in fine condition.

Did the original owners live where ethanol fuel was mandated? If not, that could be very big part of it surviving.

[moosey]

Originally Posted by booster

Did the original owners live where ethanol fuel was mandated? If not, that could be very big part of it surviving.

The vehicle was originally purchased in southern California, and spent most of its life in Fla. Only over the past 4 years has it been "living"above the Mason Dixon line...specifically here in Maine. Anyway, Maine doesn't mandate ethanol so this particular generator has been free of that issue.