BGL990
Gold Member
Just thought I'd share my bit of fun from this past weekend.
My tractor (JD 990) has always smoked a bit when cold, probably more than some others because it has no glow plugs, just an intake preheater. In the past month or two, however, it had gotten much worse. Even given that it's getting a bit cool here these days, I was getting much more acrid white smoke than normal on startup. I was mildly concerned that the injection timing had gone off or something and called a local dealer to talk to a mechanic about it. I talked to an old timer who probably knows more about diesel engines than the engineers that design them. His first question to me was how many hours on the machine and how hard has it been worked. I told him it has 100 hours and that they were pretty easy hours for the most part. I don't really have anything that works the tractor that hard. He said two things of interest. First, the engine will be barely broken in yet and I should put a good 2 or 3 hours of HARD work on it to get the rings seated before jumping to any conclusions about mechanical problems. Second, diesel fuel these days is cr*p and it could be a fuel problem.
So, I picked up new air and fuel filters, changed them out, drained the tank, and filled it with fresh fuel (with Stanadyne Performance Formula additive as always). The fuel wasn't super old, but had been sitting in the tank for probably 3 months or so. Also, we've had a very wet summer so maybe the fuel had absorbed some moisture. Whatever the cause, the old fuel came out fairly dark – sort of like a mild iced tea color. When I re-started the engine (btw. I love the self bleeding Yanmar engines!) it smoked pretty bad for maybe 45 seconds. About the length of time I would expect for the old fuel left in the injection pump feed line to be used up. After that, the smoke diminished to a much more reasonable level. Problem #1 solved – the smoking was bad fuel.
Now for the fun part, a bit of piston ring seating action. I've got an old 5 tine cultivator and my neighbor graciously let me rip up one of his hay fields with it (our pasture has too many rocks). I put the tractor in B range, 2nd gear (effectively 5th out of 9 forward speeds) and went flat out for about 2 hours. I had the tractor 100% full throttle the whole time and adjusted my speed by adjusting the depth of the cultivator. I kept it around 2000 rpm, sometimes bogging down to 1000, sometimes reving up 'till the governor took over. For the most part, however, it was running absolutely flat out, pulling as hard as it was capable of. I quite enjoyed it. A bit of wheel spin, the sound of a hard working diesel, the wee bit of black smoke as it chugged away, the smell of fresh dirt. All good stuff /forums/images/graemlins/cool.gif
Just so everything didn't go too smoothly, after an hour or so I sprung a leak in the power beyond kit I installed earlier this year. I thought I got a whiff of hydraulic oil once or twice, but didn't think too much of it. Luckily my neighbor came out to see how it was going and noticed the oily mess all over the back of the tractor. He watched while I operated the 3pt and found that each time I lifted it up one fitting was peeing a nice stream of oil out. A quick trip back to the garage and I found the fitting was just a bit loose and the pressure had finally extruded the O-ring out in one spot. A quick fix and I was back out playing.
So, in one weekend I learned a few things:
1. Even an “old timer” agrees with the current trend toward working an engine hard to break it in rather than babying it.
2. If your fuel is starting to turn dark, consider it somewhat suspect, especially if you are experiencing any engine oddities.
3. Don't ignore any abnormal smells (or sounds I'd say). If my neighbor hadn't noticed the hydraulic leak, I might have pumped all my expensive Amsoil fluid all over his field and made a serious mess of my transmission (it's a gear machine, so would have merrily kept pulling even with a dry transmission).
4. Working your tractor really hard is pretty fun /forums/images/graemlins/grin.gif
My tractor (JD 990) has always smoked a bit when cold, probably more than some others because it has no glow plugs, just an intake preheater. In the past month or two, however, it had gotten much worse. Even given that it's getting a bit cool here these days, I was getting much more acrid white smoke than normal on startup. I was mildly concerned that the injection timing had gone off or something and called a local dealer to talk to a mechanic about it. I talked to an old timer who probably knows more about diesel engines than the engineers that design them. His first question to me was how many hours on the machine and how hard has it been worked. I told him it has 100 hours and that they were pretty easy hours for the most part. I don't really have anything that works the tractor that hard. He said two things of interest. First, the engine will be barely broken in yet and I should put a good 2 or 3 hours of HARD work on it to get the rings seated before jumping to any conclusions about mechanical problems. Second, diesel fuel these days is cr*p and it could be a fuel problem.
So, I picked up new air and fuel filters, changed them out, drained the tank, and filled it with fresh fuel (with Stanadyne Performance Formula additive as always). The fuel wasn't super old, but had been sitting in the tank for probably 3 months or so. Also, we've had a very wet summer so maybe the fuel had absorbed some moisture. Whatever the cause, the old fuel came out fairly dark – sort of like a mild iced tea color. When I re-started the engine (btw. I love the self bleeding Yanmar engines!) it smoked pretty bad for maybe 45 seconds. About the length of time I would expect for the old fuel left in the injection pump feed line to be used up. After that, the smoke diminished to a much more reasonable level. Problem #1 solved – the smoking was bad fuel.
Now for the fun part, a bit of piston ring seating action. I've got an old 5 tine cultivator and my neighbor graciously let me rip up one of his hay fields with it (our pasture has too many rocks). I put the tractor in B range, 2nd gear (effectively 5th out of 9 forward speeds) and went flat out for about 2 hours. I had the tractor 100% full throttle the whole time and adjusted my speed by adjusting the depth of the cultivator. I kept it around 2000 rpm, sometimes bogging down to 1000, sometimes reving up 'till the governor took over. For the most part, however, it was running absolutely flat out, pulling as hard as it was capable of. I quite enjoyed it. A bit of wheel spin, the sound of a hard working diesel, the wee bit of black smoke as it chugged away, the smell of fresh dirt. All good stuff /forums/images/graemlins/cool.gif
Just so everything didn't go too smoothly, after an hour or so I sprung a leak in the power beyond kit I installed earlier this year. I thought I got a whiff of hydraulic oil once or twice, but didn't think too much of it. Luckily my neighbor came out to see how it was going and noticed the oily mess all over the back of the tractor. He watched while I operated the 3pt and found that each time I lifted it up one fitting was peeing a nice stream of oil out. A quick trip back to the garage and I found the fitting was just a bit loose and the pressure had finally extruded the O-ring out in one spot. A quick fix and I was back out playing.
So, in one weekend I learned a few things:
1. Even an “old timer” agrees with the current trend toward working an engine hard to break it in rather than babying it.
2. If your fuel is starting to turn dark, consider it somewhat suspect, especially if you are experiencing any engine oddities.
3. Don't ignore any abnormal smells (or sounds I'd say). If my neighbor hadn't noticed the hydraulic leak, I might have pumped all my expensive Amsoil fluid all over his field and made a serious mess of my transmission (it's a gear machine, so would have merrily kept pulling even with a dry transmission).
4. Working your tractor really hard is pretty fun /forums/images/graemlins/grin.gif
