I have a 2005 BX1500. It’s the 2 cylinder Diesel engine. I have 370 hrs on my tractor. It’s run fine up till now but when recently started (sitting about 2 weeks since last used), it started but after 20 seconds, began running rough and the engine was vibrating. The scary part was it was putting out black smoke that smelled awful. It will still restart but it does the same thing. Does anyone know what issue I’m having? I’d like to have a general idea before I haul it to the dealer and put myself at their mercy. Thanks.
Engine issue
- Thread starter Kubota Joe 1500
- Start date
Lil Foot
Well-known member
Lifetime Member
Equipment
1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
No, I’m sure of that. I had fresh winterized diesel in my yellow can. Tank was filled the last time I had snow to move (April). None added since. Worked fine for snow and other chores u
Do what Jim L Suggested. Sounds like not enough air to burn the fuel...black exhaust = unburnt fuel...I think anyway!
I have a BX1500 and recently had an issue where I was losing RPMs - not as bad as what you are describing but new fuel filters fixed it. Unless you have done both very recently I would change both fuel filters and the air filter as advised above and see what that does.
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kubotafreak
Well-known member
Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
Black is burnt fuel/over fueling, white is unburnt. If we are being diesel specific.Do what Jim L Suggested. Sounds like not enough air to burn the fuel...black exhaust = unburnt fuel...I think anyway!
I think you have some heavy water in your fuel.
Just trying to understand, but if there if over fueling, where does the oxygen come from to burn the extra extra fuel?
Perhaps it turns to carbon, like when coke is made from coal with lack of oxygen for combustion?
I have seen those tricked out diesel pickups some guys have, that belch black smoke when pushed a bit. Always assumed it was unburnt fuel due to not having enough oxygen to combust the excess fuel injected into the cylinders.
For or some reason I thought white exhaust might be a sign of water in the fuel. Obviously no expert here...g
Edit: Kubotafreak, I must be older than I realize. looks like I just repeated what you said
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Those “bubbas” think they’re “cool” by tinkering with their fuel-injection to run overly-rich. It’s against the law and in most states can be reported for enforcement by reporting a “smoky” vehicle but you have to get the vehicle description/lic. plate if making a report. It’s very annoying if you’re sitting behind them in traffic and having to breathe that stuff.
Back to this thread-topic: Be sure to check that you don’t have mud daubers or mouse-nest etc in your intakes or have a collapsed air filter which restricts air flow and causing a rich mixture.
kubotafreak
Well-known member
Equipment
GRAND l6060, L3560, B6100, gr2100, tg 1860, g1800, g1900, g2160
All good!! probably means we share the same experiences... Water can cause both white and black smoke in a diesel. It really just depends on the engine and other factors like injector type. Im just trying to stay simple given how the OP described the suddenness of the issue.Just trying to understand, but if there if over fueling, where does the oxygen come from to burn the extra extra fuel?
Perhaps it turns to carbon, like when coke is made from coal with lack of oxygen for combustion?
I have seen those tricked out diesel pickups some guys have, that belch black smoke when pushed a bit. Always assumed it was unburnt fuel due to not having enough oxygen to combust the excess fuel injected into the cylinders.
For or some reason I thought white exhaust might be a sign of water in the fuel. Obviously no expert here...g
Edit: Kubotafreak, I must be older than I realize. looks like I just repeated what you said
Henro, think about you burning something with a flame. It almost instantly turns black from carbon soot. However if you were to keep burning it, the residue burns away as well. Same with the diesel engine. If it does not fire/crack off at all the fuel is white, simply because it is a mist of fuel nothing more. If a diesel fires off at all the fuel burns. Now how long the burn sequence/amount of fuel introduced determines if the engine can reach a self clean burn in the cylinder. So this is commonly seen with the above truck example. The fuel being introduced does not have enough time to reach the complete burn/use, so it is expelled out the exhaust and you see it. Now the tricky part is why the engine does not have the ability to burn off the fuel. Low octane(dissolved water), too much fuel injected(bad injector), or engine load too high. Many factors can create the black smoke effect. Another example of water in fuel would be heavy wet fuel, separated out from the diesel. You might get white smoke, remember what I said about the engine not firing off, so the fuel/water is pushed out as a mist. Heavy water can also seize and score components, causing over fueling... so black smoke.
diesels are weird
they can black smoke under a load too even when operating properly (assuming mechanical injection and no dpf)
I had this happen on one of the few bx1500's we have in the area. A plug was out of the front of the block behind the cover and oil pressure was low inside the engine. Engine was trying to seize, sounded poor, low power, but plenty of black smoke (as if you had a mower deck bogged down in tall grass). Oil light didn't work. It eventually seized completely. Owner didn't fix it, they sold it for parts to a wholesaler.
they can black smoke under a load too even when operating properly (assuming mechanical injection and no dpf)
I had this happen on one of the few bx1500's we have in the area. A plug was out of the front of the block behind the cover and oil pressure was low inside the engine. Engine was trying to seize, sounded poor, low power, but plenty of black smoke (as if you had a mower deck bogged down in tall grass). Oil light didn't work. It eventually seized completely. Owner didn't fix it, they sold it for parts to a wholesaler.
I liked Jim L’s idea of mouse nest cause that’s what it smelled like. Found none though. I’m thinking must be watered fuel/clogged filter. I ordered a Racor water separator and waiting for it. I’ll give her a complete service with all filters and fluids while she’s in the shop. Thanks to all who replied. Great bunch of guys.
Engine issue resolved. I got and installed my Racor water/fuel separator. I eliminated the inline filter under the tractor and put in a new inline filter between the separator and the injection pump. Tractor starts and runs smoke free, vibration free and as well as it ever has. So, watery fuel was the issue and now I should have a means to control that going forward. Thanks to all who offered help. Your suggestions saved me having the dealer fix what I could fix myself.I liked Jim L’s idea of mouse nest cause that’s what it smelled like. Found none though. I’m thinking must be watered fuel/clogged filter. I ordered a Racor water separator and waiting for it. I’ll give her a complete service with all filters and fluids while she’s in the shop. Thanks to all who replied. Great bunch of guys.
