YM2210 Vent Tube?

[Smoody]

Ok, I am not sure what this tube is called, I have some oil/wet stuff that sometimes comes out this tube, but not always, seems to do it when I have to turn it over more then a few times to crank it. Its minimal but I think this is called blow by? How much is to much and is it normal to occasionally get this?

I also have a YM2001 but the tube is extended down far enough to where as if it has it it spits it on the ground, so I can't compare.

Second, is it normally harder to start a 2 cylinder vs. a 3 cylinder yanmar? my YM2001 cranks right up first turn no matter temp, the YM2210 takes a few turns on a cold morning, and puffs out white smoke while its trying to start, after it starts the smok clears and I can shut down and crank back with 1 turn.

All this normal?

SEE pic for the tube im referring to, this is a picture I got off the internet so its not my actual tractor. The "red circle" is to show where the nasty stuff blows out onto the tractor frame.

Thanks

 

[deepNdirt]

it is a crankcase vent to prevent Crankcase pressure buildup, just as your pistons build compression in the cylinders they also can build up pressure on the down stroke in the crankcase, usually you wouldn't notice any oil coming from the vent tube, it is design to relief vapor pressure do to windage of the internal engine components and the pressure of return stroke from the pistons, when the engine is cold your oil level builds higher in the oil pan and the rotation of the crank will pickup the oil and disperting it creating windage/ pressure, as the engine warms the oil thins and can move thru the engine more freely, usually when you start seeing oil around the vent tube would be a good time to change the oil, if the oil gets too thick it will not move thru the engine freely causing the oil returns to clog and then build excessive crankcase pressure,

 

[Smoody]

Thanks DeepNDirt, that's explains it better. however I did just change the oil last week (Rotella 15w-40), however I am not sure if it done it before or after the oil change, I didnt notice it until yesterday. I cleaned the soot off the frame and I guess I'll know soon enough.

 

[California]

The vent tube is operating normally, ignore it. Cars used to vent to the ground like that. Then smog rules required retrofitting PCV's (Positive Crankcase Vent plumbing) which route that smog back into the intake so you don't see it.

As the pistons go down the air in the crankcase gets compressed, and that tube lets the crankcase 'breathe' to outside. Of course a worn engine will have more pressure in the crankcase, and coming out that tube, due to compression that got past the rings.

2 cyl vs 3 cyl starting. I was amazed that the 3 cyl YM186D I bought recently starts instantly. Even faster than any gas engine. My 2 cylinder YM240 used to fire on the first compression stroke but take a couple of revolutions to smooth out. Now running B90 biodiesel it doesn't start as readily and can take 5-10 seconds of smoky cranking before it fires off. I topped up the YM186D with B100, about B50 blend in it now, and it still starts instantly. I suppose improved starting was one of the reasons for upgrades beyond 1970's technology. I still prefer the 2 cylinder engine's torque however!

 

[normde2001]

Ideally your crankcase should have a vacuum, as measured by a "manometer". If there is pressure instead, could be a bad vent, (PCV), should only let air out, not in, bad head gasket, rings, plugged exhaust, or even bad dipstick seal. Bad HG or plugged exhaust could be a reason for your hard starting.

 

[tallyho8]

As the pistons go down the air in the crankcase gets compressed, and that tube lets the crankcase 'breathe' to outside.

I was under the belief that as one piston went down the other one came up so they did not compress the air in the crankcase but maintained steady pressure.

 

[California]

Approximately, but you still need some venting.

Off-topic trivia: I first started reflecting on this when I learned my BSA (ancient British motorcycle) had side by side cylinders that went up and down in tandem, like an oversize single. This made it even-firing, one impulse per 360 degrees of crankshaft rotation. The downside was a huge volume of air, smoke, and oil droplets forced out the crankcase vent with each stroke. This was directed at the chain and described as a 'feature' essential for lubing the chain.

Then Honda entered the American market with 250 and 305 twins. 'Scrambler' (high pipes, no low end torque) and 'Dream' (touring trim) if I remember correctly. Both idled real fast with a curious loping rhythm. This was a combination of a light flywheel and pistons that rose alternately, giving a firing pattern of one cylinder firing 180 degrees after the other, then nothing for another 540 degrees of rotation. At the time the traditional motorcyclists dismissed this design as crackpot like an electric motorcycle or something. Actually Honda soon buried the British in the light-bike market. Honda's biggest advantage? Their motorcycles didn't make a puddle of oil where they were parked! As you noted, the near constant crankcase volume meant little to no oil pushed out the breather.

These Yanmar twins are like Hondas - The cylinders rise alternately and they fire 120/540.

 

[Kernopelli]

Approximately, but you still need some venting.

Off-topic trivia: I first started reflecting on this when I learned my BSA (ancient British motorcycle) had side by side cylinders that went up and down in tandem, like an oversize single. This made it even-firing, one impulse per 360 degrees of crankshaft rotation. The downside was a huge volume of air, smoke, and oil droplets forced out the crankcase vent with each stroke. This was directed at the chain and described as a 'feature' essential for lubing the chain.

If I remember correctly, Harley used to use it as a chain oiler as well. The difference in the Wisconsin 2 cyl.THD and TJD engines was their firing order, the THD's fired together and the newer version TJD used a 180* crank. Hard to imagine how they figured a twin would run better without opposing each other to some degree.

 

[careyo63]

After getting use to an old 2cyl. 650 Spec.Yamaha years ago made my Yanmar 2TR20A pretty sweet and bring back some memories thank goodness without all the vibration

 

[Smoody]

So to be clear is some wet stuff coming out of the crankcase tube normal or should it not do it at all?

 

[normde2001]

So to be clear is some wet stuff coming out of the crankcase tube normal or should it not do it at all?

Shouldn't be any, if all is good, oil at correct level. My YM2000B has none. Never noticed if it blows air out. Easiest to check is plugged exhaust.

 

[California]

I ran my YM240 (essentially the same engine) this afternoon then thought to look at that vent for you. It is dry.

But the old pre-smog cars I owned years ago were always moist there. I think this can be blowby, past the rings, or water vapor evaporating out of the oil as the engine warms up.

 

[SpaldingTractors]

when I see anything coming out the the vent tube (to me) thats not a good sign.
steve

 

[Smoody]

Just to make sure all is clarified, this tube does not "blow out" anything constantly, and it has only blow out a finger tip size of oil/gunky/watery substance 2 times, both times after cold starting it.

I know I said it was oil, but after inspecting its more watery, the tractor does sit outside but it always coverd with a heavy duty tarp and I have a metal can over the muffler to keep rain out.

Tractor runs great, no power loss and only smokes under a load, powershift changes with ease, no leaks on the machine. I was just curious as to why this mixture very randomly comes out the crankcase tube.

Thanks all.

 

[clemsonfor]

after running mine this weekend for 2 eq. hours, while letting cool down idleing i checked the tube as i was down there and thought about you. The tube appears oily, yet i have never seen a drip under the tractor. I did remember putting my finger to it to feel any pressure, there was none but i did have a tiny say half to 1/3 drop that when my finer was there it came off. This was after bushhoging and bouncing on some rough areas and had tiltited to that side on a side slope so i dont know if that contributed to it? Like i said after it has been sitting on my concreate carport or onthe trailer it has no drops that fall from that point. My guess is the oily tube if from vapors or oil mist? BUt i do not usually see any thing dripping or blowing out of this tube.

 

[Smoody]

Thanks clemsonfor, I have yet to see a drip of fluid under my tractor from this, no white smoke or mist coming out either. Just a smidge of oily/watery stuff left on the frame. I don't think its that serious, or at least no immediate overhaul needed. I cleaned the frame and plan to monitor it over the next few weeks.

I read that the 2 cyl is always harder to start then a 3 cyl, so that eased that worry a bit, anyway, if this thing did need an overhaul in the future what kinda price range am I looking at? just curious. I gave $2800 for the tractor and I changed the fluids, replaced the warning light panel, new air filter and changing the hydro fluid in the next few weeks.

One more question, looking at the muffler, there is black carbon buildup in it, I guess that's normal? How do I clean the muffler?

 

[clemsonfor]

unless its cocked up (the muffler) i would not worry about it. Its just clamped to the manifold so take it off and i guess you could run water through it or deisel fuel to rinse out the inside and then blow it dry? Mufflers and pipes get sooty they have burned hydrocarbons through them go stick your finger in your trucks tail pipe and it im sure runs cleaner than a 30 year old diesel tractor .

On the rebuild i have no idea the cost. That would depend on if your just buying the parts to do it your self or haveing a mecanic do it and then it would depend on his labor price and what he does to it. By tthat i mean will he jsut rering the pistons and put new bearings in it or will it need new liners or crank turned, new pistons, etc. etc.

-nate