YM240 smokes heavily, lacks power

[kenmac]

Looks like black smoke at full throttle. Like when I get on my diesel truck hard.. Possible injector /fuel related. If your getting too much fuel in the engine. Check your oil & see if it's showing over full

 

[winston1]

I've gone back and looked at your pictures real close. Pictures can be decieving. The smoke looks in between white and black. looks grey. Do you say it is black or grey?

 

[284 International]

I'd say the picture colors are pretty close. The smoke is dark gray, I would say. When throttling up it looks black, or when any load is placed onto the engine (trying to drive, raising or lowering the bucket, etc) it goes darker to black, when at low throttle or decelerating it's more blueish.

The oil level is in the middle of the operating range and seems to have stayed there the whole time.

It "seems" like the tractor uses more fuel than it should for the little bit of driving around I've tried to do, but I don't know how to gauge that. In less than 30 minutes of operation (never being worked hard, just driving around the yard) it has used about 1/4 inch of fuel in the tank.

 

[kenmac]

My guess would be injector problems or possible injector pump timing

 

[Gary Sweat]

Check that the fuel bowl or filter is not sucking air into the fuel. I had that problem a few days back. The engine had no power and smoked. Couldn't take off in high gear. It had never done that before I changed the filter. It turned out to be the fuel bowl was not seated all the way and was sucking air. Strange thing is, it didn't leak at the fuel bowl

Once I pulled it apart and reseated the filter in the bowl the engine ran fine with full power and no more smoke.

 

[284 International]

I pulled the fuel bowl today when I drained the tank and replaced it with different fuel. That doesn't mean it isn't leaking still, since I may have reinstalled it the same wrong way as before. I don't think the fuel bowl is the problem, but I'll see if I can find a replacement filter and carefully check the bowl, too.

What color was your smoke, Gary? This is dark gray when at full throttle with no load. I can drive around in high gear, but it doesn't really have any power.

For clarification, Winston1: I don't think it's the fuel itself. What I topped off with was fresh from the pump, and went into my pickup at the same time. I've driven 150 miles in it since then. I replaced that fuel with diesel from another station today, and the same symptoms appeared. I'm trying to get all the low-hanging fruit, which is why I don't have an air filter on it at the moment, to eliminate that as a possibility, and why I used two sources of fresh diesel, and removed the muffler.

I guess it's time to move on to more involved levels. I don't have a service manual yet, but have seen valve clearances are supposed to be 0.008 on the intake and exhaust, as well as 0.006 for both. The only numbers I've found for head bolt torque is 127 to 133 ft-lbs. Are those measurements correct, are the units supposed to be Newton-meters? (That would work out to around 97-98 lb-ft of torque) To what specification are the injectors supposed to be torqued?

I'm getting a bit discouraged: This was supposed to be a simple, straightforward re-assembly to get a tractor to use around the property. It has become a source of frustration instead. Thank you to all who have helped me so far, I really appreciate your assistance. Merry Christmas.

 

[Gary Sweat]

I pulled the fuel bowl today when I drained the tank and replaced it with different fuel. That doesn't mean it isn't leaking still, since I may have reinstalled it the same wrong way as before. I don't think the fuel bowl is the problem, but I'll see if I can find a replacement filter and carefully check the bowl, too.

What color was your smoke, Gary? This is dark gray when at full throttle with no load. I can drive around in high gear, but it doesn't really have any power.

For clarification, Winston1: I don't think it's the fuel itself. What I topped off with was fresh from the pump, and went into my pickup at the same time. I've driven 150 miles in it since then. I replaced that fuel with diesel from another station today, and the same symptoms appeared. I'm trying to get all the low-hanging fruit, which is why I don't have an air filter on it at the moment, to eliminate that as a possibility, and why I used two sources of fresh diesel, and removed the muffler.

I guess it's time to move on to more involved levels. I don't have a service manual yet, but have seen valve clearances are supposed to be 0.008 on the intake and exhaust, as well as 0.006 for both. The only numbers I've found for head bolt torque is 127 to 133 ft-lbs. Are those measurements correct, are the units supposed to be Newton-meters? (That would work out to around 97-98 lb-ft of torque) To what specification are the injectors supposed to be torqued?

I'm getting a bit discouraged: This was supposed to be a simple, straightforward re-assembly to get a tractor to use around the property. It has become a source of frustration instead. Thank you to all who have helped me so far, I really appreciate your assistance. Merry Christmas.

My symptoms were I had to pull the throttle 2/3rd the way back and it felt like it was running on one cylinder at lower rpms. The smoke was kind of gray when it started up but went to black as soon as I gave it a lot of throttle. It would pull itself around in all but high gear but ran really ruff. I first thought I had an injector problem but it turned out that the new fuel filter I installed did not go all the way up on the bowl shaft and that held the bowl off just enough to let air into the fuel.

 

[284 International]

I will make sure to look at that possibility then, it seems similar to what I'm experiencing. Thanks for the tip.

 

[KWentling]

I had a Miller Air-Pack welder with a Deutz diesel that smoked black terrible and would even die. Thought air filters would fix it, but didn't. Changed the fuel filter and it ran like a champ. May or may not be your problem, but worth a try.

Kim

 

[California]

I have some random thoughts on this. Wish I had some real advice!

If it ran nice one day and badly the next it doesn't sound serious. And the clanking about-to-scatter racket is normal for these, if a little unnerving.

That smoke isn't normal, nor the fuel consumption. These run an extraordinary long time on little fuel. I estimate a half gallon or less per tach hour (1.5 wristwatch hours approximately) doing real work. For your tinkering I would expect the fuel consumption to be unmeasurable.

Could it be working real hard to overcome resistance in the hydraulic system? The 3-point lever should be pulled full back to lift, then let forward a little to relieve the load after full height is reached.

Or could that loader circuit be loading it down? I never heard of a chain-driven hydraulic pump on these so that might be connected wrong, too. Fluid should cycle freely out to the valve and back to the reservoir except momentarily when you use the lift or curl levers to send fluid to the cylinders.

I like Winston's theory of the fuel filter sucking air somehow.

I don't know why a head gasket problem would increase fuel consumption like you describe.

I assume the injector pump is good if you can get the thing started. Look for evidence the pump was removed and tinkered with. I found lock-tite on the pump mount bolts so it was obvious it had never been off. (I stopped with the first bolt, didn't pull it!) There isn't anything an owner can do to the injector pump besides making a mess of it.

That smoke and hard running sounds like power is created then lost somewhere, probably as heat. Does the hydraulic fluid get hot?

Obviously if the head was off and the previous owner gave up because he couldn't fix it, there could still be a head gasket leak or maybe a cracked head letting coolant into the intake. (I expect a leak into the the exhaust wouldn't affect how it runs). Can you look into the intake and exhaust with a flashlight when you hear that sizzling?

The Hoye instructions are for appraising the individual injector spray patterns. But a bad pattern should make starting difficult so I don't think the problem is there. I would put on a heavy welding glove, use a long wrench, and loosen each fuel line at its injector to see if letting the fuel escape and not reach the injector affects each cylinder equally. (Similar to shorting each spark plug to identify a weak cylinder). If each cylinder is contributing equal power, the problem has to be external to the head/block.

Wish I had some better ideas!