I have about 3k hours on my EF2000iSv2. It is about 1.5 years old, made in China and I bought it new. On on startup lots of blue smoke pisses out the exhaust. If the eco mode is left off after start the blue smoke clears. This is a new problem that began a few weeks ago.
When the sun is near sunset and shining right on the generator, I can see blue smoke but it isn't thick enough to capture on video. It has always done this. The oil/blue smoke can be smelt whenever it is running. A camper complained to me about it once. Since new, it has used oil between oil changes. I top it off every other day.
I'm looking to fix at least the startup smoke issue. What could be the problem(s)?
I thought about taking it back, but I'd need to buy another generator to replace it. Another observation is it doesn't always huff smoke. The hard to see blue smoke I can live with, it was the startup huffs that bugged me. This week it hasn't been a huffer. I wonder if oil level and/or level of the generator would contribute to blue smoke. What do you think? I use it out in the desert and won't know if the generator is actually level to the horizon.
digitalnomad, I have an EF2000iSC that has 86 hrs on it and it does not use oil. Oil usage is caused by 3 different parts, all of which wear out very, very slowly when the motor is regularly maintained and not abused. Abuse would be running it near the rated load in full sun on a hot day or using it for multiple eco idle low power very short run times in cold weather.
Those parts are:
1) The cylinder wall surface (damaged by dislodged carbon deposit particles or environmental dirt fines that sneaked past the air filter). Since it has been using oil for a while you should have heavy combustion chamber carbon deposits.
2) The intake valve stem rubber seal. With age, a high run time and heavy loads the rubber heat hardens and wears out. (it is inexpensive and very easy to replace). That is the 1st thing I would replace (with the piston @TDC!!). Try and wobble the valve stem to see if it has excess side play.
3) The valve cover breather check valve (gunked up or loose reed, or reed is bent away from sealing off the passageway opening). It can fail to maintain the required slightly negative crankcase pressure, then allowing oil to be forced pass the valve stem clearance and be burned in the cylinder.
Not having the Genny level is easy to fix. Place it on a 3 foot x 2 foot rectangular sheet of 3/4" plywood and check for level, with a level and make it level! Then overfilling the oil is not possible.
With proper oil changes and regular servicing of the air filter foam, while ensuring that the foam element has a leak free seal against the air filter housing, your Genny will age gracefully with you.
I appreciate the detailed response, Rob. The generator has used oil since I bought it brand new. In fact, after a couple days of use after purchase it shut down. That was my introduction to the low oil feature. On one hand I was glad it had the feature, on the other hand it shouldn't have happened.
I'm hoping it doesn't have a bad oil ring. I'm going to check the valve cover breather check valve. Maybe it is stuck. Would an un-level surface cause excess oil usage?
digitalnomad I would make the easy shots first, check:
3) The valve cover breather check valve. Here's a really easy way to test its function without using any socket wrenches. Remove the breather hose coming from the valve cover at the other end where it connects to the carburetor air intake tube for purposes of a crankcase breather check valve function test. Put a 2" tall object like a 2x4 piece of lumber under the 2 rubber feet on the carburetor/oil fill side to tilt the oil level away from the threaded oil fill opening so oil will not be blown out of the opening. Remove the dipstick, then put your mouth on the air intake tube end and try to blow air into the valve cover, where you should feel near solid resistance. There may be some very slow leakage which is normal. Next, apply suction to it, where you should feel very little resistance. The importance of this test is to confirm there is a dramatic difference between the blowing and suction tests, because when the underside of the moving piston forces the crankcase pressure to change in the positive/negative direction once per one revolution of the crankshaft, at an idle or 3,600 RPM it effectively maintains a partial negative atmospheric pressure in the crankcase airspace. That not only reduces oil being pushed past the intake/exhaust valve stem clearance, it also relieves the stress and prevents oil weepage past gasket surfaces and the 2 crankshaft oil seals. BTW, that blow/suck test is a very good function test for anyone to use on any single or twin cylinder power equipment engine to easily check the performance of a very important engine component that is subject to wear/breakage/contamination, causing heavy oil usage and oil weeping or leaks.
2) The intake valve stem rubber seal. Since it has used oil since new, getting an engine where the rubber seal may be torn, have not been fully installed or is missing, that is your 2nd test to do, requiring at least a 10mm socket, ratchet and extension using the method in my 1st response.
What should have been done before there was over 10 hours on it was take it to the Yamaha dealer to register a complaint it has been emitting blue smoke and using considerable oil since brand new. That's because they won't act on it then, saying it needs more break-in run time. It's still on warranty, isn't it?
Thank you for the instructions, Rob. I'm going to test the check valve when I come across a 2X4. For now, I'll just keep adding more oil.
Yes, the generator is under warranty. It has been about 1.5 years since I bought it new at a Yamaha dealer in Vegas. They also have a service shop. The easy thing to do would be to bring it in. But I'd need to replace it at that point since I need a generator to survive out in the wild.
Rob, I decided to just replace the valve cover breather check valve. There has been a big increase in blue/oil smoke on the first startup of the day. Turning it off then back on clears it instead of just letting it run. It has not puffed smoke when I pull the start cord a few times with the ignition off.
No, it's not the rubber hose! The check valve is riveted to the internal underside of the ($46!!) valve cover, part #9 on the same diagram.
Before you do that, be sure the check valve is not working! Disconnect Hose #12 from Pipe #13 and try the suck/blow test to confirm it behaves like a check valve: easy flow on suction, harder flow on blowing in - - - just be sure the dipstick is removed to relieve your suction/pressure actions you apply to the close system so the oil level is tilted away from the threaded opening and the oil is prevented from being "blown out". First be sure to put an object under that side of the Genny to allow air to escape from the dipstick opening.
Rob, you were right on the money. The check valve test failed. There is absolutely no pressure when blowing in nor out of the tube.
It was like blowing through an oily straw. The air went into the crankcase and out the oil filler hole and vise-versa. There wasn't any noise whatsoever from a PCV or check valve. The behavior was as if the valve is missing or stuck completely open.
Does this malfunction sound like the root cause of oil consumption?
I'm wondering if a valve stem seal is flaky too. That part is cheap. I'm not sure I want to give Yamaha $50. If the valve is there, is there any access to fiddle with the internal component to get it unstuck after removing the valve cover?
Yamaha was unhelpful and Yamaha of Las Vegas where I bought the generator was unresponsive.
"Does this malfunction sound like the root cause of oil consumption? " Yes.
The check valve is nothing more than a thin plastic disk floating in a confined space, centering it over the breather passageway opening. Burning oil since new means it likely has never worked at all or somehow is stuck partially open. A possibility is that a piece of the hidden/internal mesh used to capture oil droplets from the "fog" vapors may have been dislodged and got stuck between the disk and the port seating surface. THAT is a warranty covered defect.
The pic link below shows my EF1000iS genny's valve cover internals, similar to the EF2000iS model.
You could remove the valve cover and take a look-see for the anomaly as you suction/blow on the attached hose. Also check the oil drain-back hole opening for a manufacturing defect. My guess is the Yamaha dealer would be "cooperative" with resolving your defective part.
If you have (or can borrow) an iPhone we could FaceTime (mine on WiFi) for further guidance as you do the above operation.
Thanks for that. From the pic, it doesn't look like I could take the breather apart and clean/inspect it. I will need to just keep running it as and drop it off at Yamaha before Nov. 2020 when the warranty runs out. I'd like to have it fixed now, but I'm not in a position to give it up without replacing it.
I'm guessing the valve stem seal will fail prematurely because of the non-functioning breather valve.
"I'm guessing the valve stem seal will fail prematurely because of the non-functioning breather valve".
Yes and No. The increased crankcase pressure pulses will press it harder against the circumference of the valve stem, but the extra oil "passing by" will keep it virtually floating on a film of oil.
Taking the valve cover off will reveal a cracked/broken/propped-up or out of position disc valve, when compared to the full contact, in place position as in the pic link above. you could also see exactly what is causing the disc valve to malfunction as you re-do the suction/blow test on the attached hose. BTW, replacing the valve stem seal IS easy, but ONLY for someone with the mechanical experience needed to do so. Anyone "winging it" could drop the intake valve into the cylinder -then- the cylinder head will have to come off to re-install it. You mentioned running in the desert (heat?), so with the ~3000 hours run-time I would have the valve stem seal replaced by a mechanic friend.
So . . . what exactly is the Genny being used for and how heavily (a guesstimate percentage) is it continuously loaded? Single source Off grid power or just a lot of camping?
Rob, great information. I greatly appreciate your input and expertise. It does sound worth while to pop the valve cover. I wasn't sure if the warranty would be voided if I removed it and started manipulating the broken breather valve. It does sound like there are cases where it could be popped into place and for that I may risk it.
I am mechanically inclined with lots of experience on cars & trucks and do have light valve stem experience on a Chevy 350 CI where I needed to replace the valve stem seals. To keep the valve from dropping, I pushed rope into the cylinder hole through the spark plug and packed it in the combustion chamber. Ghetto, but it worked to hold the valves without using an air compressor.
The generator is being used to power computer equipment. I'm a software developer. A desktop PC and a laptop. Probably 400 to 500 Watts about 8 to 10 hours a day. Every few months, I charge my Chevy Volt with it for about 30 minutes to run the generator hard since it just idles all day in eco mode. That probably does nothing, except ease my mind and add to the wear. The draw for that duration is about 960 watts (8 AMPS). The car will draw either 8 AMPs or 12 AMPS, depending on an in-car power selection. I'd run it at 12 AMPS, but the generator won't put out that amount unless I'm at sea level.
The generator does get heat from the sun. Lots of it. Plenty of rain, wind, hail and snow too, but the snow typically melts around it. As a nomad, the usage is 100% off grid power. Dispersed camping in the mountains and deserts of Nevada, California, Oregon and Utah.
Hold your horses! Yesterday I tested the breather check valve on my new orange W*n 2000W 79cc inverter genny, virtually a clone of the Yamaha EF2000iS engine/alternator design/layout. It passed air with suction applied as the metal reed sang a vibratory song, then on the blow in it resisted, passing only a very slow tiny amount of air, as expected with that simplistically crude type of one way "valve". It mimics a perfectly functional differential pressure valve to maintain a slightly negative crankcase air pressure.
Just minutes ago, after reading your post, out of curiosity I opened up my EF2000iSC and performed the same test to see how the Yamaha version would perform and what kind of sound it would make. To my SHOCK, IT SHOWED ZERO RESISTANCE TO BOTH SUCTION AND PRESSURE!! WTF??? OMG!! My only reasonable explanation is that the plastic disc needs a more powerful pressure pulse change to reposition itself. I cannot imagine not having a working check valve, especially since the EF1000iSC has one (as shown in pic). It is possible they have engineered oil tightness into the piston rings and cylinder head.
Figuring there may be a timed breather like BMW OilHeads where exit air passageways are covered/uncovered by the crankshaft as it rotates, I slowly pulled the recoil stater while rapidly applying the suction/pressure pulses . . . still with no change in airflow resistance from the valve cover at any crankshaft position. I even checked the male fitting on the "air cleaner joint" which also showed no airflow resistance in either direction. That is really puzzling in that this is the first one cylinder engine to behave as if there is NO breather check valve in the circuit. They seem to rely on the location of the breather hose's male spigot right at the opening to the carburetor, where there is continuous slightly negative pressure with violent intermittent negative pressures during every intake valve opening as the engine runs.
So, there is some other anomaly or damaged part(s) causing the heavy oil usage. Prior to removing the valve cover, be aware that it first requires splitting the blue center main covers and removing the air shroud and "other parts."
During storm Irma (9/11/17) I loaned my EF2000iSC to my neighbor where it ran 46.5 hours with only one extra recoil start. The oil level dropped to half way down the threaded fill opening without triggering the low oil shutdown. It powered a monstrous stainless steel full sized double door upright freezer -or- a 3 door kitchen refrigerator, either one of those two -plus- a big coffee maker, numerous phone chargers and table lamps on extension cords.
Again, register a complaint NOW about the excessive oil use since new. You should also provide HARD shade for the genny in hot weather, in the same way in which you would not work hard lifting heavy loads in full sunlight, for 8-10 hours without any rest .
Interesting find on the EF2000iSC. As far as the oil usage during Irma, mine is not far off of that. It has gone 3-4 partial days without a need to top-off. About 25-35 hours collectively. But your generator may get better and stop using oil after break-in.
When I called Yamaha the other day to ask about the PCV, they just referred me to the Yamaha dealer where I bought it and didn't mention any need to register a complaint. Then again, the first agent transferred me to a recorded message that ended the call. The second agent gave me the run down on how to handle warranty issues with it.
What do you think of the WEN 2000 watt generator? I'm wondering what the sine wave would look like on an oscilloscope with some of these generators. I need a pure sine wave, already went through the modified sine wave saga on a previous Champion 1200 generator. It had a good motor. Never re-filled the oil once and it ran better than the Yamaha, but it outputted a modified sine wave breaking my power supplies (and it was much louder).
I ran into someone with the Harbor Freight Predator 2000, a Honda clone. It doesn't use any oil, but the pull cord broke on it.
digitalnomad, Being you have an average Wattage draw under 600W and will run it for thousands of hours I would recommend a new Yamaha EF1000iS inverter Genny, of which I have a 2009 model and consider it my favorite one (of 5 in-house). Nicknamed it the "Doomsday Machine" since it can very quietly run my Kenmore medium chest freezer and Amana 21 CuFt Energy Star bottom freezer Refrigerator from Eco Idle, at the same time . . . . on less fuel than ANY OTHER GENNY MADE! It's also very reliable and long lived.
Another plan for less money with better power coverage and freedom from downtimes would be to get Two, yes Two WEN 56125i 1,250-Watt surge (1KW continuous) Inverter Generators @ $294.28 each at the best price from the Mfgr: Wenproducts.com More impressive is the cost for the parts. Look at the prices for the Carb, Inverter, and Stator, consider the free shipping , even for just one $4.77 Air Cleaner Element then think it over, here: 56125i Parts Because of California and PRico power woes it sells out frequently, so be patient. They are distant clones of the 50cc EF1000iS but with a 60cc engine, have readily available inexpensive parts by phone, and have a great reputation. So for $590 you'll ALWAYS have a running inverter Genny as one can be down for oil changes, a carb clean, lent to a neighbor, etc. Also they can be parralled for 2KW continuous, 2.5KW start Wattage if company shows up with electric blankets and a space heater. The biggest plus is the big historic record the 1250W and 2000W Orange/Yellow boxes have. IF you discount most of the the One Star reviews given by Bots or people that have NO clue about their machine and blame the Mfgr when they don't understand not only how to properly use it but also do NOT maintain them enough or correctly.
Last year I bought a Wen 56200i 2,000W inverter Genny (an EF2000iS clone) and it works great. Before I even started it I took it apart (ALL the plastic panels and the valve cover removed) and was impressed with what I saw. After a slowly incremental, progressive break-in with 5 complete heat cycles over a week I was ready to test it. Turning a 1,400W heat gun "On" from Eco idle the voltage very briefly dropped to 113V and the Hertz also measured by the Fluke 115 varied only from 60.04 to 60.07Hz (Wow!, that is tight) It's Orange/Black and a beauty too. BTW, on another topic Consumer Reports just rated the EF2000iS clone Harbor Freight Predator 2KW inverter genny a "Best Buy", -but- I believe the near identical twin Wen has better Tech/Parts/Phone support and it's way more handsome.
I also ran my EF2000iS last week with the side cover off just to test the valve cover breather hose output with the engine running (no electrical load). It fluttered big time, as if there was no breather check valve. Yamaha may have found out that filtering out the oil mist from the crankcase vapors and opening up the breather flow pulsations going thru a smaller diameter opening will better and very lightly lube the top end of a continuously heavily loaded engine, extending its life. So . . . don't buy a new valve cover, especially without removing the old one for inspection.