New Yamaha EF2000iS inverter Generator Oil Issue

Further to the thought that there might not be rings on the piston.

I'm just sitting here pondering this idea.

Considering the doubling of compression by adding oil to the cylinder, one would have to conclude that the problem is likely rings.

However, with no rings, I's suspect that blow-by would be considerable. Thus causing a lot of oil to be forced out the crank case ventilation tube, into the carburetor and burned in the combustion chamber producing visible smoke. Accordingly, I'm back to the idea that the rings are either defective, improperly installed, failed to seat properly or the cylinder is defective.

The wet test, has pretty much eliminated valve guide seal issues.

When I spoke to the Yamaha dealership mechanic, his focus appeared to ensure that I understood that if they tear the engine down and don't find a problem, I'm on the hook for labor. So I replied that doubling the compression by adding oil to the cylinder, would appear to confirm that there is a problem and that it's likely related to the rings or possibly a defective cylinder.

There shouldn't be an issue establishing if there's a problem. The focus should be on the cause of the problem.

Not too confidence inspiring when the mechanic appears to be dismissive of the facts that I provided him. I sometimes wonder how well trained many of these "shop mechanics" are? When I told him that I was getting 50 psi dry and over 100 psi wet, he didn't even acknowledge nor discuss that aspect. It was basically bring it in we'll look at it. He was more concerned that I was aware that I'd be paying labor costs rather than what the possible cause of the problem might be.

I think I would have had a bit more confidence in the guy had he acknowledge the info I gave him and admitted that something is abnormal.

Either way, now that I have a registered complaint with Yamaha, I might just run the generator for a while to see if the condition changes. I'll likely take in to the shop in the spring, just prior to camping season.

However, I am very much curious to find the cause of the problem.... I'll have to see if I can resist bringing it in sooner.
 
I'd put no stock in the dry vs. wet compression readings "IF" your engine has a mechanical, automatic, compression release. The only way I'd trust that reading is if the compression release was fully disabled. Who's to say the valves did not seal a couple of degrees early due to the oil, thereby changing the reading you achieved.

I'm still thinking it's a ring seating issue.

I'm going to bet a dollar that the piston has all 3 rings on it, in the proper position.
 
Originally Posted By: Cujet
I'd put no stock in the dry vs. wet compression readings "IF" your engine has a mechanical, automatic, compression release. The only way I'd trust that reading is if the compression release was fully disabled. Who's to say the valves did not seal a couple of degrees early due to the oil, thereby changing the reading you achieved.

I'm still thinking it's a ring seating issue.

I'm going to bet a dollar that the piston has all 3 rings on it, in the proper position.


I agree that the rings are probably there as you say.

However, doubling the compression by adding the oil to the cylinder is something to be considered, compression release or not. The compression release is equal in both tests. Each test takes several pulls of the start cord to get maximum reading. The dry test probably took a good fifteen to twenty pulls to achieve 50 psi. The wet test only took half as many pulls or less.

I also agree that it's likely a ring seating problem.

Accordingly, I'm hesitant to run it in for repairs right away. I'm thinking of putting a few more hours of hard running on it to see if I can get it to somewhere near normal. Problem is, I'm no longer using the camp and I'm not real enthusiastic about running it in the back yard for thirty hours.

If we have a very rare power outage, I'll definitely put it to work. Otherwise, I'll probably just wait it out until next April or thereabouts.

Really appreciate everyone's input. It will be interesting to see what the verdict is when all is said and done.
 
Originally Posted By: crainholio
Originally Posted By: JimPghPA
t escape from the passageways that were clogged.

Again this is just a theory, but I have used GC in our 3.4 Liter engine in our 2001 Impala, and the oil consumption went from, down one quart at 2K miles with Mobil Drive Clean 5W-30 5000, to down less that ½ a quart after 8K with GC 0W-30. And that made a believer out of me when it comes to GC having less oil consumption in an engine. It did take about 300 miles on the first fill of GC before the oil leaks became insignificant.


Is that with the current amber-colored GC, or the original green stuff?


That is with the current amber-colored GC.
 
Well, it's been close to a year since posting on this issue, so it's time for an update.

Oil consumption hasn't changed much that I can see. I've been keeping accurate records for hours of use, fuel consumption and somewhat less accurate oil use measurements.

The good news is that this generator is exceptionally fuel efficient. Under light loading (less than 500 watts), which is 95% of the time, it averages 3.5 hrs. per liter of fuel. That equates to 13.25 hrs. to one US gallon. Not sure about you folks, but I am impressed with that.

Oil consumption hasn't increased. I don't measure the oil too accurately but it seems to be using approx. 100 ml. ever 25 to 30 hours. I keep a 500 ml. squeeze bottle with a nozzle nearby and just squirt in enough to top it off every third or fourth refueling. I've been using 5W50 Synthetic Castrol oil and have been doing a complete oil change every 100 hrs., as per manual instructions. Don't know why? The oil always looks fresh. It should, considering that it's being replenished so often.

The machine's exhaust doesn't show smoke but, oil does slowly drip out of the exhaust pipe. This would indicate to me that the oil might be bypassing the rings and blown out of the cylinder somehow, bypassing the combustion process. Otherwise, there should be smoke, right?

Whatever is going on, doesn't seem to be having a negative effect on operation. Spark plug looks perfect whenever I pull it. Nice and tan colored with no oil residue on it. No indication of oil being blown out of the crank case ventilation tube. There's no sign of oil, where the tube exits into the carburetor intake housing. It's dry and clean.

I have to say, this is a perplexing issue. However, if the generator continues to run well providing such excellent fuel efficiency and no indications of increasing oil consumption, I think I can live with it. I'm beginning to think that the oil consumption might actually be contributing to the excellent fuel efficiency. More than likely wishful thinking....

Any comments or theories on what you might think is happening?
 
Other than because of your small sump capacity your usage does not seem extreme for the time involved in it's use in the generator. 3.4 oz for 30 hours in an air cooled sound pretty good overall. Most generator manufactures recommend checking the oil level at least every time you add fuel.

Whimsey
 
Originally Posted By: boraticus
Well, it's been close to a year since posting on this issue, so it's time for an update.

Oil consumption hasn't changed much that I can see. I've been keeping accurate records for hours of use, fuel consumption and somewhat less accurate oil use measurements.

The good news is that this generator is exceptionally fuel efficient. Under light loading (less than 500 watts), which is 95% of the time, it averages 3.5 hrs. per liter of fuel. That equates to 13.25 hrs. to one US gallon. Not sure about you folks, but I am impressed with that.

Oil consumption hasn't increased. I don't measure the oil too accurately but it seems to be using approx. 100 ml. ever 25 to 30 hours. I keep a 500 ml. squeeze bottle with a nozzle nearby and just squirt in enough to top it off every third or fourth refueling. I've been using 5W50 Synthetic Castrol oil and have been doing a complete oil change every 100 hrs., as per manual instructions. Don't know why? The oil always looks fresh. It should, considering that it's being replenished so often.

The machine's exhaust doesn't show smoke but, oil does slowly drip out of the exhaust pipe. This would indicate to me that the oil might be bypassing the rings and blown out of the cylinder somehow, bypassing the combustion process. Otherwise, there should be smoke, right?

Whatever is going on, doesn't seem to be having a negative effect on operation. Spark plug looks perfect whenever I pull it. Nice and tan colored with no oil residue on it. No indication of oil being blown out of the crank case ventilation tube. There's no sign of oil, where the tube exits into the carburetor intake housing. It's dry and clean.

I have to say, this is a perplexing issue. However, if the generator continues to run well providing such excellent fuel efficiency and no indications of increasing oil consumption, I think I can live with it. I'm beginning to think that the oil consumption might actually be contributing to the excellent fuel efficiency. More than likely wishful
thinking....


Thanks for the update. I suspect most owners do not keep such detailed records of oil in/out. If they did, I would suspect the issue to be more common. I do not measure the in/out oil in my Eu2000i, but I think I will start doing that based on your experience to determine if our experiences match up. On a side note, I've been interested in using a vaccum oil extractor to do oil changes. I've read that in some cases it will pull more oil out. In theory, if I didnt know this prior I would probably assume I was burning, if my refill was over the quantity of the last change...

Any comments or theories on what you might think is happening?
 
Originally Posted By: Ope_Freak
Originally Posted By: boraticus
Well, it's been close to a year since posting on this issue, so it's time for an update.

Oil consumption hasn't changed much that I can see. I've been keeping accurate records for hours of use, fuel consumption and somewhat less accurate oil use measurements.

The good news is that this generator is exceptionally fuel efficient. Under light loading (less than 500 watts), which is 95% of the time, it averages 3.5 hrs. per liter of fuel. That equates to 13.25 hrs. to one US gallon. Not sure about you folks, but I am impressed with that.

Oil consumption hasn't increased. I don't measure the oil too accurately but it seems to be using approx. 100 ml. ever 25 to 30 hours. I keep a 500 ml. squeeze bottle with a nozzle nearby and just squirt in enough to top it off every third or fourth refueling. I've been using 5W50 Synthetic Castrol oil and have been doing a complete oil change every 100 hrs., as per manual instructions. Don't know why? The oil always looks fresh. It should, considering that it's being replenished so often.

The machine's exhaust doesn't show smoke but, oil does slowly drip out of the exhaust pipe. This would indicate to me that the oil might be bypassing the rings and blown out of the cylinder somehow, bypassing the combustion process. Otherwise, there should be smoke, right?

Whatever is going on, doesn't seem to be having a negative effect on operation. Spark plug looks perfect whenever I pull it. Nice and tan colored with no oil residue on it. No indication of oil being blown out of the crank case ventilation tube. There's no sign of oil, where the tube exits into the carburetor intake housing. It's dry and clean.

I have to say, this is a perplexing issue. However, if the generator continues to run well providing such excellent fuel efficiency and no indications of increasing oil consumption, I think I can live with it. I'm beginning to think that the oil consumption might actually be contributing to the excellent fuel efficiency. More than likely wishful
thinking....


Thanks for the update. I suspect most owners do not keep such detailed records of oil in/out. If they did, I would suspect the issue to be more common. I do not measure the in/out oil in my Eu2000i, but I think I will start doing that based on your experience to determine if our experiences match up. On a side note, I've been interested in using a vaccum oil extractor to do oil changes. I've read that in some cases it will pull more oil out. In theory, if I didnt know this prior I would probably assume I was burning, if my refill was over the quantity of the last change...

Any comments or theories on what you might think is happening?


Sorry i screwed up my last post...


Thanks for the update. I suspect most owners do not keep such detailed records of oil in/out. If they did, I would suspect the issue to be more common. I do not measure the in/out oil in my Eu2000i, but I think I will start doing that based on your experience to determine if our experiences match up. On a side note, I've been interested in using a vaccum oil extractor to do oil changes. I've read that in some cases it will pull more oil out. In theory, if I didnt know this prior I would probably assume I was burning, if my refill was over the quantity of the last change...
 
I bought a small drill driven vane pump to extract oil from the generator. I used it twice then put it away for good. It seems like a good idea but, in reality, it isn't as quick nor effective as tilting the machine over on it's side to drain the oil. I just close the vent for the fuel tank, remove the side panel, remove the oil plug and drain the oil while it's hot. I have everything set up so that I can lay the machine on it's side and leave it in that position for a complete drain. The way Yamaha designed the cabinet makes for minimal spillage and it works quite well.

In all of my years of small engine ownership (lots of years and lots of engines), I've never had one that used this much oil. Come to think of it though, my 2007 Simplicity snow blower has a 305cc B&S engine that uses about an oz. of oil in three hours or so of hard use. So, using that ratio, that would be ten oz. in 30 hours. However, that's a 305cc engine working hard vs. an 87cc engine loafing along.

Regardless, the Yamaha's oil use is forgiven as long as it keeps giving me such excellent fuel efficiency.
 
My only thought was that some OPE engines will not show oil consumption due to fuel dilution of the oil. This is quite common on air cooled engines. In other words, there is some oil consumption, but it's displaced by partially evaporated fuel and combustion by products. The oil gets dirty quickly.

This is very common on aircraft engines operated in cold environments.
 
Pretty sure there's no fuel dilution happening with this machine. Good point though.

What's most perplexing is that oil literally drips off of the end of exhaust pipe and it's relatively clean? That tells me that it's not likely experiencing combustion.

I'm having trouble getting my head around that aspect. No blue smoke, no sooty spark plug, fairly clean oil dripping from the exhaust. Oil must be escaping past the oil ring for sure and past the compression rings as well. OR.... the exhaust valve guide seal is leaking oil? However, if that was the case, one would think that the some of the exhaust gas would blow past the defective seal and into the valve cover, thus blowing oil out the crankcase ventilation tube and into the carburetor intake housing, which isn't the case.

I guess this mystery will remain as such until something lets go or oil consumption gets right out of hand. Still got a couple years on the warranty. Hopefully if something goes wrong, it will be sooner than later. If it keeps on performing as well as it does I can live with that.

I'm anal when it comes to maintenance anyway. Giving it a shot of oil every so often is no problem. I just have this curiosity thing going with the oil consumption. It's simply a matter of trying to understand what the cause could be????
 
Been doing some research on the Yamaha EF2000is. Haven't come up with anything regarding oil consumption.

However, I did find news that I find a bit disconcerting. If anyone is thinking about buying one of these, beware. It appears that some of them are being built in China. I know that I will NOT buy a Chinese built Yamaha - anything.

More food for thought, how does Yamaha build the same machine in both Japan and China and charge the same price?

Seems to be more reports of problems with the Chinese built units as well.

Here's a very informative link: http://ghost32writer.com/?p=6127

What the [censored] is Yamaha thinking?
 
Originally Posted By: Joe72Mart
Off topic:

BTW Welcome back Borat.

I've always enjoyed reading your posts.
Stick around this time.

Joe


Thanks for the welcome back.

I was very busy all year and didn't put too much thought into participating in forums.

Now that I'm seeing a glimmer of light at the end of the tunnel, I'll likely have more time to indulge. However, I won't be spending my winters in the north anymore. Last winter was so cold and long, that it finally pushed me over the edge. We're moving out of our house here in the woods and into a condo in town.

I've disposed of my snow blowing equipment, and will be hanging up my snow shovel. Heading south baby! And won't be back until April.

We will still have the camp however and will be keeping all of our grass cutting/trimming equipment, chainsaws, water pumps, outboards, ATVs and other gas operated machines. So, I'll likely still have some interest here albeit at a somewhat diminished level, that I'm certain, will please some members.....
 
China or not, people are getting 13,000 hours out of these things! Stunning lifespan. It seems the trick is to remove the muffler's screen to prevent clogs. Otherwise, they are long life units.
 
Originally Posted By: Cujet
China or not, people are getting 13,000 hours out of these things! Stunning lifespan. It seems the trick is to remove the muffler's screen to prevent clogs. Otherwise, they are long life units.


I pulled the screen on my machine on day one. I keep the machine housed inside a building and manufactured/extended the exhaust pipe to discharge outside. My machine only has 350 hours on it so far.

The lifespan of the Japanese built EF2000is is pretty well documented and as previoulsy mentioned, very impressive. Not certain how well the Chinese units are faring. Not sure if they've been around long enough to rack up the hours. Time will tell I guess.

Either way, I'm not convinced that the Chinese assembled machines will be on the same quality level as the Japanese built units. I'm happy to sit back an let others carry out that experiment.
 
Originally Posted By: boraticus
Originally Posted By: Cujet
China or not, people are getting 13,000 hours out of these things! Stunning lifespan. It seems the trick is to remove the muffler's screen to prevent clogs. Otherwise, they are long life units.


I pulled the screen on my machine on day one. I keep the machine housed inside a building and manufactured/extended the exhaust pipe to discharge outside. My machine only has 350 hours on it so far.

The lifespan of the Japanese built EF2000is is pretty well documented and as previoulsy mentioned, very impressive. Not certain how well the Chinese units are faring. Not sure if they've been around long enough to rack up the hours. Time will tell I guess.

Either way, I'm not convinced that the Chinese assembled machines will be on the same quality level as the Japanese built units. I'm happy to sit back an let others carry out that experiment.


I agree, Borat, seems like they should sell for less if sourced from China. Same thing with the new Toro's running chinese (Loncin) engines. Interestingly, there is not a huge price reduction in Toro equipment since switching from brand name suppliers to Chinese. Sure, they can't market they are selling products for less since they are getting killer deals on Chinese motors. Nobody would buy them. Toro would probably agrue its necessary to keep overall costs reasonable.
 
Originally Posted By: Ope_Freak
Originally Posted By: boraticus
Originally Posted By: Cujet
China or not, people are getting 13,000 hours out of these things! Stunning lifespan. It seems the trick is to remove the muffler's screen to prevent clogs. Otherwise, they are long life units.


I pulled the screen on my machine on day one. I keep the machine housed inside a building and manufactured/extended the exhaust pipe to discharge outside. My machine only has 350 hours on it so far.

The lifespan of the Japanese built EF2000is is pretty well documented and as previoulsy mentioned, very impressive. Not certain how well the Chinese units are faring. Not sure if they've been around long enough to rack up the hours. Time will tell I guess.

Either way, I'm not convinced that the Chinese assembled machines will be on the same quality level as the Japanese built units. I'm happy to sit back an let others carry out that experiment.


I agree, Borat, seems like they should sell for less if sourced from China. Same thing with the new Toro's running chinese (Loncin) engines. Interestingly, there is not a huge price reduction in Toro equipment since switching from brand name suppliers to Chinese. Sure, they can't market they are selling products for less since they are getting killer deals on Chinese motors. Nobody would buy them. Toro would probably agrue its necessary to keep overall costs reasonable.



The irony of it all is that having product assembled in China is supposed to be to keep manufacturers competitive. One would think that using Chinese components or having products built in China would result in price reductions? If everyone is using China as a main component of their manufacturing process, then everything built there should be less expensive.

Companies like Toro and Yamaha are obviously resting on their laurels. They've chosen to incorporate China into their manufacturing process yet do not pass any of their cost savings on to their customers. They're increasing their profits and we, who buy their Chinese built equipment may very well be buying products not in the same class as those made elsewhere.

I know that I will be very discriminating when purchasing anything new and will certainly be looking at country of origin vs. price.

Don't take this as a China bash. It's not. I know there are good products that come from China. However, there are a lot of not-so-good products from China as well.

Two years ago I had purchased a Hyundai HY2000si inverter generator that was built in China. Thought the Hyundai name would have upped the ante somewhat in quality. Initial evaluation and opinion of the machine was good, although it was a bit on the heavy side. Power output was good due to the 125cc engine, which started, ran very nicely and used no oil! Anyway, that honeymoon was over at 175 hours when the machine self destructed.

Prior to the stator shattering the magnets, the machine blew it's inverter. I replace the inverter, fired up the machine and the stator/rotor let go. Talk about disappointing.

The Chinese are very good at making a product look well made - from the outside. However, look deeper into the machine and there are glaring examples of poor quality of components as well as manufacturing assembly.

A buddy of mine bought a Chinese Boliy inverter generator that began leaking oil profusely only after a few months of ownership and very little use. He brought it to me to look at it. The screws for the valve cover were finger tight? I tried to adjust the valves and the lock nuts were so tight, that I was afraid I'd break something trying to back them off. So, no valve adjustment. Gave the machine back to him and a month or two later, he called me again because it wouldn't start. The choke mechanism had fallen off the carb. Fixed that and a few weeks later, the choke lever broke off. The machine has sat unused now for close to a year and I'm finished with wasting my time on it. Nothing but trouble.

I know that you don't judge the quality of country's entire output on two examples. However, they're the only two Chinese built generators that I've been exposed to and both are/were total disappointments.

In the case of Hyundai, it would appears that the Chinese have dragged Hyundai down to their level rather than aspiring to achieve the level of quality that Hyundai has recently achieved. Let us hope that Yamaha and other leading manufactures, do not allow this to happen to them.
 
Oil consumption update.

Well, it's camping season again and the EF2000is has been put back to work since the last week of April. I've put maybe 50 or 60 hours on it this year and not much has changed. Oil consumption is consistently the same, about 100 ml. every 30 hours or so. No smoke from exhaust but clean oil does accumulate at the end of the exhaust extension pipe. Fuel consumption is spectacular. With the light loads it's used for, we consistently get 3.8 to 4 hours (sometimes better) per liter of fuel. Amazing fuel efficiency.

I've come to the conclusion that the oil consumption/fuel efficiency is a reasonable trade off. As long as those figure remain the same, I'm OK with that.

Speaking of oil consumption, I read somewhere about Honda cars using too much oil and owners complained. Honda apparently stated that the oil consumption was a result of efforts to increase fuel economy. Anyone else ever hear of that?
 
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