# Dark oil - too dark?



## FlyFisher (Jun 30, 2018)

This is the oil out of my Honda EU2200i. I ran it for about 4hrs yesterday/wednesday with a mix of motor loads (fan and shop vac, not sure on the wattage draw but the shop vac barely runs and I have to flip the switch fast to get the motor to start without tripping the inverter off - with eco mode off). In any event - I figured it was due for a refresh. I am not sure on the hours, but I assume it has 30-40 hours since new so its well past its break in period, I admit (manual shows 20hrs for break-in change). 

I was a bit freaked when I started draining the oil - it looked black. After sampling it the color isn't black, its just a real dark amber.

Oil was Pennzoil 10w30, dino not synthetic. 

I replaced it with Pennzoil 5w30 synthetic.





















While I'm at it - another unit I have I sampled the oil from for the heck of it. I don't think this round of oil has more than about 20 hours on it and it is an old generator, just doesn't see much use. I changed the oil in it a couple years ago. Other than 2 ~4 hour power outages and various load tests I haven't used it, I use the EU2200. 

The oil in this unit has some sediment in it that was obviously settled out. I ran the generator about a week ago for a few minutes, so it has been recently run (hasn't sat for months and months).

You can clearly see the separation of the sediment (I am calling the darker stuff sediment, it does not appear to have any grit to it) in both the stuff draining from the container and the stream coming out the drain.






















Thoughts?


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## iowagold (Jan 22, 2020)

yup...
try castrol oil.
that is what honda likes.
and run a magnetic dipstick.


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## Dutchy491 (Sep 18, 2019)

Thoughts? Yep, you’re using a good car Oil but in a hot running air cooled small engine. The dark colour is due to some combustion byproducts and some of the lighter Oil components burning off. If you came to my shop I would advise you to use Amsoil Small engine Oil that is specifically made for small engines. I run the Amsoil 10w30 in all my small engines and 10w40 in some of the local saw mill engines, gas/diesel. This Oil has high ZZDP levels to minimize wear. If you don’t want to run Honda branded Oil use a motorcycle Oil. It’s more suitable for those small engines than a car Oil. Also change it yearly even with low run time. pm me for a link to Amsoil Small Engine Oil or just goggle it. Dutchy


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## speedy2019 (Jan 29, 2019)

I haven't really thrashed me generator or used it for a long period of time since having it just over 2yrs ago and been used for about 15hrs in total. I have changed the oil once and checked it about a month ago and so far the oil looks as clean as when it was new. And doesnt appear to use much oil at all, as it hasnt used any since the beginning of winter. Its a cheap genny aswel, so Im quite impressed with that.Electric Key Start Generator | Bohmer-AG - 6500W-e Portable Generator


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## Dutchy491 (Sep 18, 2019)

That’s where we get complacent. Not much use other than a maintenance run now and then, cheap unit so why over do it etc etc. Until the #%£! hits the fan. Now we worry about how well the unit holds up, fingers crossed.😬Cheap unit or expensive unit, both benefit from the best care possible. If you play the game of “ what can I get away with” it will bite you when you least expect it. Same with fuel storage. Always always mix in some name brand fuel treatment. My 2 cents, Dutchy


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## speedy2019 (Jan 29, 2019)

Dutchy491 said:


> Thoughts? Yep, you’re using a good car Oil but in a hot running air cooled small engine. The dark colour is due to some combustion byproducts and some of the lighter Oil components burning off. If you came to my shop I would advise you to use Amsoil Small engine Oil that is specifically made for small engines. I run the Amsoil 10w30 in all my small engines and 10w40 in some of the local saw mill engines, gas/diesel. This Oil has high ZZDP levels to minimize wear. If you don’t want to run Honda branded Oil use a motorcycle Oil. It’s more suitable for those small engines than a car Oil. Also change it yearly even with low run time. pm me for a link to Amsoil Small Engine Oil or just goggle it. Dutchy


I use this semi synthetic oil 10w-40 (-15c to 50c temp range) in my genny, https://www.amazon.co.uk/MANNOL-10256600500-Defender-10W40-SL/dp/B004ND8AQQ/ref=sr_1_2?crid=KMY5WMT3D8N4&dchild=1&keywords=mannol+10w40&qid=1621478442&sprefix=mannol+10,aps,214&sr=8-2&th=1




Dutchy491 said:


> That’s where we get complacent. Not much use other than a maintenance run now and then, cheap unit so why over do it etc etc. Until the #%£! hits the fan. Now we worry about how well the unit holds up, fingers crossed.😬Cheap unit or expensive unit, both benefit from the best care possible. If you play the game of “ what can I get away with” it will bite you when you least expect it. Same with fuel storage. Always always mix in some name brand fuel treatment. My 2 cents, Dutchy


 Well not much point paying stupid money for something I use maybe once a year... The 15hrs I have clocked up on the genny are all exercise hrs accept maybe 3hrs, so no point having a expensive genny, not for my use anyway.


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## Matt88-8 (Dec 27, 2018)

Yup, looks like mildly dark oil. Don't sweat it even slightly. Seriously. it's a air cooled, splash lube engine. If its not used in cold weather throw 15w40 diesel oil in there and send it. If it is used in cold weather use a 5w 40 syn. and change it once a year.

Sent from my SM-G973W using Tapatalk


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## Dutchy491 (Sep 18, 2019)

Well not much point paying stupid money for something I use maybe once a year... The 15hrs I have clocked up on the genny are all exercise hrs accept maybe 3hrs, so no point having a expensive genny, not for my use anyway.
[/QUOTE]
True for you. But I have many customers with over 10000hrs on their various small engines. Even one that’s over 20000. But these are engines that run almost every day and so are an integral part of everyday life for these folks. Nothing but the best maintenance because everything depends on a good running engine. We don’t rely on small engines in the same way.....until the electricity stops. Dutchy


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## iowagold (Jan 22, 2020)

amen dutchy!
yea zddp rocks for sure!
never had any luck with pensoil...
the inside of the engines always looked like what you drained out!
the amsoil is good stuff, honda oil is real good!, and castrol 10-30 is what they teach in honda school.
you need an oil that will take getting beat up....
so low foaming etc.
that small engine amsoil works for that!
same on the castrol.
and then royal purple rocks.
we add the zddp in every oil change on the small engines.
pm if you need links


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## speedy2019 (Jan 29, 2019)

Dutchy491 said:


> True for you. But I have many customers with over 10000hrs on their various small engines. Even one that’s over 20000. But these are engines that run almost every day and so are an integral part of everyday life for these folks. Nothing but the best maintenance because everything depends on a good running engine. We don’t rely on small engines in the same way.....until the electricity stops. Dutchy


Im hope if I keep my gen well maintained, it will last me 200-500hrs, so thats about 20yrs with the use it gets.. But I havent ever properly used my gen with multiple loads at the same time and for 2+hrs at a time...But the 8bhp engine does run really smoothly even when cold, and if I keep doing the monthly exercise runs, checking/changing the oil etc, theres no reason it should fail on me when I need it, is there?


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## Dutchy491 (Sep 18, 2019)

Maybe you could let us know in 20 years? 😉


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## FlyFisher (Jun 30, 2018)

Back to the original subject at hand in the thread... 

I did note the condition of the spark plugs in each unit when I took them out the other day. 

This is the one out of the EU2200i. It looks like it has a good bit of oil deposits. That seems like that would follow suit with the dark oil that came out of it. The unit runs just fine, but I am curious if I should look at it a bit closer. I can keep tabs on the plug and oil next time I run it (might be used for a good while in a couple weeks, then possibly the last weekend in June for a couple days).











This is the one out of the older rotary unit:










I cleaned both plugs with a wire brush, rag, a flat blade screwdriver for some extra scraping, and brake cleaner to get some more of the gunk off. Gaps are both around .6mm.


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## iowagold (Jan 22, 2020)

never wire brush a spark plug clean.
replace or sand blast it with the special media..
any metal scraping on the porcelain will leave metal behind.

yea change oil brand and type before you do any more damage to the gen set.
you are real close now to having to do a full engine tear down...

on a new gen set dark oil is a bad day on a gen with 40 hour run time oil changes...
the spark plugs should look like the second one with that low of hours unless the foam air filter is over oiled!
and yes that is a known issue.


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## speedy2019 (Jan 29, 2019)

I think most of us use a wire brush to clean a spark plug?


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## Dutchy491 (Sep 18, 2019)

FlyFisher said:


> Back to the original subject at hand in the thread...
> 
> I did note the condition of the spark plugs in each unit when I took them out the other day.
> 
> ...


Not good if you’re seeing Oil residue on the spark plug from the 2200. It is a newer unit. I’m thinking that it could be some carbon buildup due to short cool runs? Change to a new plug. Then every maintenance run have it run minimum 30 minutes with a good load like a small heater and not on eco Mode. Check the plug at the next Oil change. I Bet the plug wouldn’t look that bad again if run with a load each time. You might also want to check the spark arrestor for carbon buildup! Iowa might be right that the air filter has been over oiled too? Dutchy


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## Airstreamer67 (Oct 3, 2020)

Dutchy491 said:


> Well not much point paying stupid money for something I use maybe once a year... The 15hrs I have clocked up on the genny are all exercise hrs accept maybe 3hrs, so no point having a expensive genny, not for my use anyway.


True for you. But I have many customers with over 10000hrs on their various small engines. Even one that’s over 20000. But these are engines that run almost every day and so are an integral part of everyday life for these folks. Nothing but the best maintenance because everything depends on a good running engine. We don’t rely on small engines in the same way.....until the electricity stops. Dutchy
[/QUOTE]

OK. That's the deal: expensive units for extensive use.

But, the vast majority of gensets in home use today are not extensively used. A few hours a year on average is about what most homeowners' generators see.

I know my home generators have averaged about two dozen hours a year over the past 25 years, and I live in a hurricane zone near the Gulf Coast. Some years, no usage at all. Some years, a week's usage at a time.

But this type of home usage is not at the level of the 10,000 hours or 20,000 hours usage that some may see, usually commercial or off-the-grid users. These are very different situations than what most homeowners face.


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## FlyFisher (Jun 30, 2018)

Airstreamer67 said:


> But this type of home usage is not at the level of the 10,000 hours or 20,000 hours usage that some may see, usually commercial or off-the-grid users. These are very different situations than what most homeowners face.


Agreed. This isn't to argue the point of the "screamer" class (air cooled 3600rpm) generators being used in those high-hour environments, however that is the territory for "prime use" units. By "prime use" I am referring to the lower RPM units that run at 1800 RPM with liquid cooled and pressurized oil engines. In more recent times fuel injection adds to the mix also. Think car/truck/(big) tractor engine vs a lawn mower engine. Totally different animals for totally different uses and lifespans. Even in the same "generator" use/environment the two classes of engines are totally different animals - and for good reason. 

Though, to at least make the point while I'm at it - I'll use a 15kw class generator as an example. A "screamer" 15kw unit is still "portable". They are heavy, but still somewhat portable units that you can tote in the bed of a pickup truck. Mine, for example, is around 250-300lbs (no frame cage, just C channel base frame). An example of a similar "prime use" unit is the Winco DR1214. It is actually a 12.5kw unit, smaller wattage. The base unit weighs about 1,800lbs. For it to be mobile you would need a trailer for it - either its own trailer (they have that option) or have it loaded/mounted to a utility trailer of some kind. "Mobile" and "Portable" are two different things. A 200kw semi-trailer generator is "Mobile" also, but dragging a trailer around for your power source might be out of the question if you truly need a "Portable" class generator - and for that class, speaking of the smaller wattages, you're limited to the air cooled, splash lube screamers. 

I am not aware of any smaller generators (under 10kw or so) that even have pressurized oil engines. They are all splash lube. To tell the difference - if it uses a spin on oil filter its pressure lube. Briggs & Stratton in the past 3-4 years (I think) came out with a line of commercial V-Twin engines (they made some major upgrades to their Vanguard series) that was to compete with the Honda GX series. From what I have heard, those have held their own in their respective markets (commercial mowers, pressure washers, etc) so both the big B&S and Hondas I'd say are pretty good quality today. And both are examples of pressurized oil "screamer" engines for larger portable generators. Neither company, though, uses pressurized oil on their single cylinder engines that are used up to about 8-10kw size generators - they are all splash lube.


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## Airstreamer67 (Oct 3, 2020)

Good points. That's why it's important to differentiate what the generator buyer's needs are. 

Buying an $8000,1800RPM, water-cooled generator with a pressurized oil system when an $800, 3600RPM, air-cooled splash-type oil system will serve his/her needs is a waste of money.

The heavy-duty unit will last longer for commercial and off-grid applications, but likely no longer than the light-duty unit for the average homeowner.


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## JJ Ranch (Apr 23, 2021)

My Perkins 3 cylinder industrial diesel engine generator running at 1800 rpm has a life span of probably 10,000 hours. It will serve me until my demise and then the future owners of our ranch for years and years. I consider it a ranch upgrade that is a great investment for the long term.


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## tabora (Sep 6, 2018)

speedy2019 said:


> I think most of us use a wire brush to clean a spark plug?


Or the wire wheel on the grinder...


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## Airstreamer67 (Oct 3, 2020)

JJ Ranch said:


> My Perkins 3 cylinder industrial diesel engine generator running at 1800 rpm has a life span of probably 10,000 hours. It will serve me until my demise and then the future owners of our ranch for years and years. I consider it a ranch upgrade that is a great investment for the long term.


Yep, for heavy usage, that big 10,000 hour diesel is the way to go! 

But for my home use as averaged over the past 25 years, it would take me 400 years to wear it out.


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## iowagold (Jan 22, 2020)

lol tab or just use the grind wheel like dudley moore making keys in Arthur part 2..
i never laughed so hard!

they make a special spark plug air blaster kit you can get them as summitt racing.
they work ok!

for 2-3 bucks i just replace the plug!
not worth the time to repair!


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## FlyFisher (Jun 30, 2018)

I decided to poke a bore scope through the spark plug hole on the EU2200. Looks like the top of the piston is a bit crusty too. 

Thoughts? 

My time estimate on the unit is somewhere around 30-50 hours since new (bought new).

The times I use the generator it runs at idle 99.9% of the time - the loads aren't enough to rev up the engine except for the occasional start up load with a bigger tool like a heavy drill or circular saw. I ran a shop vac off of it the other day for maybe 5-10 minutes - thats the hardest the generator has ever run and it barely ran the shop vac (with eco mode off I had to flick the power switch on the shop vac to get the vac motor to start without tripping the overload on the generator, once it started the generator seemed to keep up with it, albeit at pretty high RPM - but that was the only time its ever run like that for more than a quick test).


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## iowagold (Jan 22, 2020)

looks like 2000 hours!
or bad rings!
or crankcase vent failure!
wow!
tear down time.


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## Dutchy491 (Sep 18, 2019)

How did you break it in, ECO mode? Good luck with that if you did. Like I said earlier run the heebeegeebees out of it with a heavy draw like a heater and see if it runs better afterwards. Other than that here’s a good example of what happens with poor poor maintenance. Dutchy


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## FlyFisher (Jun 30, 2018)

Dutchy491 said:


> How did you break it in, ECO mode? Good luck with that if you did. Like I said earlier run the heebeegeebees out of it with a heavy draw like a heater and see if it runs better afterwards. Other than that here’s a good example of what happens with poor poor maintenance. Dutchy


Pennzoil 10w30 (regular, non-synthetic) oil out of the box. Aside from that, I've run it with light loads in eco mode 99% of the time. 

I have no issues with it running - it runs perfect. There was no "problem" with it that prompted the thread. What prompted the thread was I decided to change the oil in it and noted that the oil was dark and the spark plug had some crust on it (see earlier pictures). That didn't seem right. Again, there is no issue with the engine running - it runs perfect. That's the problem with the almighty Internet - people see something down in a thread without the context and say "fire fire boom boom". Where we are in the thread is just the pictures and speculation that it all looks odd. As to why - theories have been expressed such as piston rings or some other passage of oil from the crank case to the combustion chamber. That has NOT lead to a "problem running the engine" yet, but the goal is to prevent things from getting there.


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## Dutchy491 (Sep 18, 2019)

I understand. So what does Honda say regarding the breakin procedure?


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## FlyFisher (Jun 30, 2018)

Dutchy491 said:


> I understand. So what does Honda say regarding the breakin procedure?





FlyFisher said:


> I am not sure on the hours, but I assume it has 30-40 hours since new so its well past its break in period, I admit (manual shows 20hrs for break-in change).


As for time - I'm just guessing on the 30-40-50hr amount. It has run over-night camping a couple times, I'm guessing those total runs were maybe 32-38hrs combined, not each. The rest has been maybe an hr or two here or there. If the unit had an hour meter on it that would be a no-brainer, but it does not have one (I realize there are hour meters that can be installed - that might help for future maintenance intervals).


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## tabora (Sep 6, 2018)

FlyFisher said:


> Looks like the top of the piston is a bit crusty too.


I had a PowerMate PM1500 that I purchased in 1991 and ran it until 2018 in an insulated truck box with an 8" exhaust fan for cooling. I had to take the head off about every 4-5 years to clean the carbon and crud out. It just never got run hard enough (25-50% load) and in a very hot environment. I sold it last year and it still started on the first pull and ran perfectly.


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## iowagold (Jan 22, 2020)

you should run a gen with a 50-75% load and eco off for the 100 hour break in period.
and yes first oil change at low hours like 5 to 20 hours.
then again at 50 hours and again at 100 hours.

something is up as it should not look like that till it has over 1000 hours...
i would not run it any more till you get it cleaned out.
crust in the rings can and will tear up the bore...
and you want to check the rings!
they could be put on wrong!

for me as a service shop all the alarm bells are going off!
lol
something is up!

take your time tearing down and check all the specs along the way.

and on all eu2000i and 2200i gens do the cam belt at 5 years of hard run and at 10 years.
it requires a tear down for that.


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## Airstreamer67 (Oct 3, 2020)

Has any data been produced to determine the effects on a genset from running on "eco" mode for significant periods of time?

I ask that because it's not unusual for an engine to carbon-up at slow and idling speeds and low loads.

The high use of the "eco" mode would be my "guess" about why the crusty piston top.


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## speedy2019 (Jan 29, 2019)

tabora said:


> Or the wire wheel on the grinder...


That a bit extreme to clean a sparkplug on..lol



Airstreamer67 said:


> OK. That's the deal: expensive units for extensive use.
> 
> But, the vast majority of gensets in home use today are not extensively used. A few hours a year on average is about what most homeowners' generators see.
> 
> ...


I have only used my gen for 2hrs during powerloss in the last 2 and a bit yrs, so theres no point of me having a expensive gen


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## FlyFisher (Jun 30, 2018)

iowagold said:


> you should run a gen with a 50-75% load and eco off for the 100 hour break in period.


What is hard about that is I don't have any real purposes for running the generator with any "significant" load. That, and the fact it is quiet, is why I got it in the first place. My other older unit is a "screamer". For light loads - running power tools, fans, computers, or a ham radio power supply once in a while, for example - I am not running high loads at all. 

In order to load to 75% I would have to intentionally "load it up" and let it run. That seems like a waste of fuel and wear on the unit. That would be akin to plugging in a heater and just blowing hot air to get the load up when all I need is a small wattage supply. Or, just power up the unit at home to do the loading and let it run with no need for generator power period. That's counter-intuitive. 



Airstreamer67 said:


> Has any data been produced to determine the effects on a genset from running on "eco" mode for significant periods of time?
> 
> I ask that because it's not unusual for an engine to carbon-up at slow and idling speeds and low loads.


Something that catches my attention is that the piston top looks "oily" - it doesn't look like dried crust it is greasy like the drippings from a smoker.

As to the tear down - I can try to work on that next week. Up to about next tuesday (8 days from now) is packed pretty good so I won't get a chance to do much tear down. I don't want to start in to it and have to leave it then not have everything fresh in my head when I get back to it. 

Are there any special tools - like E sockets - that anyone knows I'll need? I don't have E sockets, but I worked on dads generator several years ago and the carb stack is attached with E studs. I made do with a small socket, but would have been better with the right tool. With some down time it would be a good idea to get things coming if need-be.


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## McCorby (Apr 26, 2021)

iowagold said:


> you should run a gen with a 50-75% load and eco off for the 100 hour break in period.
> and yes first oil change at low hours like 5 to 20 hours.
> then again at 50 hours and again at 100 hours.
> 
> ...


Please tell me you are joking regarding a 100 hour break-in. Lol! If done correctly, a typical IC engine requires 2 to 6 hours to break-in. The biggest things to remember when breaking in an engine are to vary the load and speed (hard to do on a generator that’s not an inverter and/or not equipped with eco mode!!!) and avoid sustained high loads during the first few hours of operation. This is how I would break-in a Honda EU engine.....
0 - .5 hours: Do not use eco mode. Randomly vary the load between no-load and 25% of rated continuous load.
.5 - 1 hour: Randomly turn eco mode on and off to vary engine speed. Randomly vary the load between no-load and 50% of rated continuous load. Only run at 50% load for no more than 30 seconds at a time.
1 - 1.5 hours: Randomly turn eco mode on and off. Randomly vary the load between no-load and 75% of rated continuous load. Only run at 75% load for no more than 30 - 60 seconds at a time.
1.5 - 2 hours: (or up to 6 hours of if it makes you feel more comfortable!) Randomly turn eco mode on and off to vary engine speed. Randomly vary the load between no-load and rated continuous load. Only run at rated continuous load for no more than 30 - 60 seconds at a time.
After breaking in.......run it like you stole it! 😜

As for flyfisher’s engine.....to say it likely needs a complete teardown seems very premature in my opinion. Pictures can be very deceiving. I would perform leakage and compression tests. If they have access to a bore-scope, they can also better verify the condition of the cylinder. No matter what, I would do these checks before even considering tearing the engine down. YMMV!

Flyfisher.........

Is it burning/using oil? If its not, and leakage and compression are good........and it can handle rated load, I highly doubt you have piston or ring issues.

How long do you let it run with the choke on? I’ve seen people run with the choke on for way too long. This can lead to excessive carbon build up and fuel dilution of the oil. You should turn the choke off as soon as it is possible after starting a cold engine. After the engine starts, and as much as the engine will allow, gradually adjust the choke toward the off position. Then with the choke off, let it warm up for a few minutes before applying a load. A fully warmed up engine, that’s properly tuned, should not require choke to start.

Also, do you keep eco turned off until the engine is fully warmed up? This will also help reduce carbon build up and fuel dilution of the oil.


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## FlyFisher (Jun 30, 2018)

I have a mirror for the bore scope so I will poke it in the hole again and see if I can get a glimpse of the cylinder walls.

Although, I had to take the thread protection ring off the camera to get it to fit inside the hole. So I am not sure that will work - the mirror screws on those threads = might not pass through the spark plug hole.

As for choke and eco mode - 

I start with choke, eco mode off. Once its running I take choke off. If it is running a bit rough at start up I will cycle the choke on and off, but not for a sustained period of time. That may only be a few seconds. Once its running I put it on eco mode. 

The times I've run heavier loads (like the shop vac example the other day) I will take eco mode off. That is a rare occasion, though. 

I would confidently say that more than 95% of the overall run time thus far has been at idle in eco mode. 

I did not get a sense that the oil was low when I drained it. It was up in the tube on the crank case and measured fine on the dipstick. 

Another mechanic buddy of mine questioned the deposits on the cylinder as being oil entirely. He is thinking it may be from fuel.


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## McCorby (Apr 26, 2021)

I would agree that it is more likely caused by fuel rather than oil. Running in eco mode under light loads for extended amounts of time can cause carbon buildup. A carbureted small engine‘s combustion efficiency and its intake & exhaust scavenging efficiency at low speeds and light loads is not the greatest. This can result in fuel dilution and carbon buildup In the combustion chamber. I would recommend running at higher speeds and loads occasionally to help burn off these carbon deposits. This will also help prolong the life of your spark plug.


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## FlyFisher (Jun 30, 2018)

Ah success! The mirror made it through - albeit with a shoe horn and some care but it went. 

I'm not an expert, but I see more scoring from the boring of the cylinder than I do rub marks from the rings... 

Thoughts?


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## FlyFisher (Jun 30, 2018)

Tested compression. Looks like 65-70 PSI. I did a bit of browsing online and it looks like people are getting 50-70 so this is on the upper end of the range. That is a good thing.


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## Dutchy491 (Sep 18, 2019)

Yep, so once again I say to work that little genny with a heater hooked up. Yes it's a waste of energy doing this, but it preps the motor for working efficiently later in life. Kinda like a marathon runner practicing prior to race day... Your compression numbers look promising too. Now do as your told. LOL Dutchy


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## McCorby (Apr 26, 2021)

Like I said earlier, pictures can be deceiving. To get clear and detailed images of the cylinder wall you really need to use a high quality bore scope that uses a fiber optic light source.

As for the compression, I do not know what that spec is for this engine, but what you measured doesn’t seem to be out of line. I do know the spec for my Honda HS928 snowblower is 85 - 121 psi, but this spec varies depending on the engine.


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## tabora (Sep 6, 2018)

speedy2019 said:


> I think most of us use a wire brush to clean a spark plug?





tabora said:


> Or the wire wheel on the grinder...





speedy2019 said:


> That a bit extreme to clean a sparkplug on..lol


Nah... Been doing it that way for nigh on 60 years. And I don't have to buy many spark plugs as a result of getting them REALLY clean.


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## iowagold (Jan 22, 2020)

yes on the 100 hour break in.

hummm is there a chance you slipped up and got 2 cycle fuel in this gen set???
or mix of gasoline and diesel?
yea we see that on job sites..
gesiel or dasoline makes a mess out of a good working fuel system.
depends on the mix of those fuels to what i call it! lol!
same on the older 16 to one 2 cycle in a 4 cycle engine...
but if you have later stihl synthetic 50 to one mix it will burn out or the cyl over time. 
that low ash stuff!

yea that stuff builds up in the rings and makes a mess!

i think if every thing was reported right to us 
it could be a flipped ring or not put together right oil ring set.
rare but it could happen!
with low hours you might want to have a new ring set on hand and swap out the rings
looks like the hone marks are still heavy on the walls.
make sure they are off set proper on the open part of the rings.
even on the multi piece oil rings. 
make sure the ring gaps are off set.

also make sure to clean the exhaust screen or check it now for oil on that screen
you have to remove the muffler to get to that!

there is a flapper on the side of the engine to check action for the crank case vent.
pull the carb and see inside the intake runner if there is oil just before it enters the combustion chamber.

as far as tools the service manual shows the tools required.
as well as the steps. and all the go / no go dimensions of the parts for specs.
you will need a fly wheel puller for small gx honda or make one.
from there it is all ISO japan on the Phillips screws
and metric on the rest of the sockets.
take pix as you go to doc the parts.
use lots of baggies for the parts and mark the bags as steps of removal.
lots of different lengths of the same bolt and screw dia used in these units.
pm if you need a link for the honda bond to seal the crankcase.
as well as tools.


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## speedy2019 (Jan 29, 2019)

My gen doesnt like the choke at all, as the engine sound rough and the longer its on for the rougher it sounds. So I turnoff the choke as soon as its starts, but might leave it on for a few seconds if its really cold. (I think if I left the choke on longer than 20secs, the engine would probably run so rough it would die) The engine purrs like a cat as soon as the choke is turned off though.


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## McCorby (Apr 26, 2021)

iowagold said:


> yes on the 100 hour break in.


Can you please show me where a small engine manufacturer recommends a 100 hour break-in procedure for their engines? I have been in the small engine development and testing profession for nearly 30 years. I have helped develop and document break-in, durability, and performance test procedures for a number of small engine manufacturers throughout my career. Break-in procedures typically look similar to what I posted above. I have never heard of a small engine break-in procedure that extends past 2 to 6 hours. Now, if you mean it can take more than 6 or 8 hours for some engine components to fully break/bed in, then yes you are correct. But after a few hours of initial break-in you are good to go. You do not need to do anything special after that.......other than be sure to change the oil after the break-in is completed.....and again 20 or so hours after that.

FlyFisher, I do not recommend tearing the engine down without a competent small engine mechanic taking a look at it first. With the limited information you have provided and without actually having “hands on” the engine, someone on the internet can not properly diagnose what your issue is or if you actually even have an issue that warrants a complete engine teardown! Just say’n!


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## FlyFisher (Jun 30, 2018)

McCorby said:


> FlyFisher, I do not recommend tearing the engine down without a competent small engine mechanic taking a look at it first. With the limited information you have provided and without actually having “hands on” the engine, someone on the internet can not properly diagnose what your issue is or if you actually even have an issue that warrants a complete engine teardown! Just say’n!


With the compression checking as it did I am OK with it for the time being. I don't like the looks of the gunk on the piston, but perhaps getting it hot will burn it off. 

For what its worth, I've worked on dozens of engines over the years - from small .049 glow RC engines (the old Cox single speeds as well as some Norvel .061's with throttles) up to the 6.7l diesel in my truck. So tearing in to equipment doesn't really phase me. I'd rather not do it, though, unless really warranted. Yeah, everyone has different opinions on condition - what looks like something to one person says something entirely different to another. 

If things don't improve then I'll figure out a tear down plan.


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## FlyFisher (Jun 30, 2018)

iowagold said:


> hummm is there a chance you slipped up and got 2 cycle fuel in this gen set???


Possibly. I had left-over marine fuel (high octane 2 cycle) that I diluted with regular gas to get rid of it in the lawn mower etc a couple years ago. I do not recall if I ran any of it through this engine, but it is quite possible. If there is any mixed marine fuel left I usually save a gallon or two and have it on hand for my chain saw. I don't like having extra mixed fuel so I keep things separate until I need it (our 2 main boats/motors run straight gas - one is a 4 stroke Merc and the other is a new ETec 2 cycle - but it is oil injected and requires straight gas, the other 4-5 motors are all mixed 2 strokes).


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## Dutchy491 (Sep 18, 2019)

FlyFisher said:


> With the compression checking as it did I am OK with it for the time being. I don't like the looks of the gunk on the piston, but perhaps getting it hot will burn it off.


Let us know what you find after a good long hot run. Run it for a couple of hours, but not on eco mode. I’m thinking that the goop in the cylinder and on the piston will be diminished significantly if not completely. Dutchy.


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## iowagold (Jan 22, 2020)

McCorby said:


> Can you please show me where a small engine manufacturer recommends a 100 hour break-in procedure for their engines? I have been in the small engine development and testing profession for nearly 30 years. I have helped develop and document break-in, durability, and performance test procedures for a number of small engine manufacturers throughout my career. Break-in procedures typically look similar to what I posted above. I have never heard of a small engine break-in procedure that extends past 2 to 6 hours. Now, if you mean it can take more than 6 or 8 hours for some engine components to fully break/bed in, then yes you are correct. But after a few hours of initial break-in you are good to go. You do not need to do anything special after that.......other than be sure to change the oil after the break-in is completed.....and again 20 or so hours after that.
> 
> FlyFisher, I do not recommend tearing the engine down without a competent small engine mechanic taking a look at it first. With the limited information you have provided and without actually having “hands on” the engine, someone on the internet can not properly diagnose what your issue is or if you actually even have an issue that warrants a complete engine teardown! Just say’n!


mc corby what company are you with?


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## McCorby (Apr 26, 2021)

iowagold said:


> mc corby what company are you with?


Sorry, but that is not something I want to share.


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## JRHill (Nov 19, 2020)

Airstreamer67 said:


> Has any data been produced to determine the effects on a genset from running on "eco" mode for significant periods of time?
> 
> I ask that because it's not unusual for an engine to carbon-up at slow and idling speeds and low loads.
> 
> The high use of the "eco" mode would be my "guess" about why the crusty piston top.


This is a straight out reaction to this post:

As for Eco mode use, I have a EU7000is for emergencies or the daily charging of the battery bank in the winter. We are off grid. Put it in service in Aug. 2018 and it has ~2000hrs on it now. After break in* I have kept it in Eco mode continuously including winter cold starts except if running something with on/off substantial high surge loads (like a large hand grinder, etc). Absolutely not a problem with THAT generator**. You mention idling speeds. On a genset with Eco mode there is normal and low idle. Low idle is not putt-putt-putt at no load which would not be best practices for long periods. I wouldn't do that with any small engine.

*After I considered the genset broken-in at the 200hr 2nd oil change (running Eco off) in changed over to full synthetic. I have run 5w30 or 10w30 Mobile1 year around since. The oil comes out barely tinted at 200hr interval changes. I have a magnetic dipper and there's rarely anything but a film of something magnetic on it.

**The EU7000is (gas) is a different breed being fuel injected. The injection system absolutely accommodates cold starts in the winter but needs sufficient warm up time. My system autostarts and stops the genset and the only time it runs is to charge the battery bank (and feed everything else while doing so). I just leave it at 5 minutes warm up year around. The critter is so quiet you almost never detect it running and its 15' away from the kitchen window.

As an ending, other than batteries, my greatest expense in off grid has been playing with generators - or should I say experimenting. I experimented with much generator stuff and have many memories of a middle of the night running outside to fire and warm up a generator getting my slippers filled with snow and hoping the run would be completed. Plus I had to stay awake to shut it down. When my wife retired I said NO MORE and "bit the bullet" and got the Honda. I added the auto start linked to the solar devices to start and stop the genset. Not only does it start and warm it up but it cools it down.

The story goes on from there starting last fall. I ditched the FLA batteries and went with lithium. Now I don't have corrosion points, specific gravity, distilled water, logging - nothing. ITS ACTUALLY BORING. This didn't come as a small expense. The Honda (which worked great with FLA batteries) but the main thing was fuel savings. The lithiums were expensive too. But if you tripped and fell and bonked your head on a rock can your household continue on?

This is kind of long. Doing cheap is not always cheaper. After years I believe if I was out of the picture the household we could continue on. I have about nothing to do but honey-dos. I can't blame the solar anymore. The bottom line is protecting your household is paramount. You, what happens from a drunk driver are a cat or bear or A TICK?


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