Have a L3901 w/425 hrs. Started one morning and sounded like the bottom end was trying to come through the oil pan, immediately shut engine off and pulled dip stick. oil very thin and registered a high level on stick. Carried tractor to a Kubota dealer and was told the engine would need to be replaced they were not able to rebuild! picked tractor up and removed motor myself. pulled engine and took to a well know machine shop for rebuild. was told from machine shop nothing wrong with engine, (Could tell a cylinder was dumping fuel) it was out so we went through it anyway all new pistons/bearings/ injectors ECT ECT ECT. Reinstalled engine and still has the knock maybe worse than before. Rebuilt engine was ran for probably 5 minutes, new oil is black and over full on the dip stick. Question is what sensor would cause the new injector to dump fuel? maybe a ECU problem? I'm not confident in my local Kubota dealer advice because of their original finding which was BS!!!
Fuel Knock
- Thread starter Chad P
- Start date
85Hokie
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That "knock" - you sure it is engine related? Could it be what IS attached to the engine? Pump, etc?
where you get those injectors? OEM or ????
where you get those injectors? OEM or ????
North Idaho Wolfman
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GreensvilleJay
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not OEM injectors, will have to reach out to machine shop for brand. no programing has been done to new injectors. was told by the machine shop new injectors do not require it.
North Idaho Wolfman
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I'm pretty sure you need to have the injectors programmed into the ECU for it to run properly.
That aside, it knocking should not be injectors, unless they are dumping fuel into the cylinders.
Make a video of the knock and post it on YouTube and give us a link to see it.
Could the knock be related to a lift or injection pump gone bad?
Maybe a seal leaking fuel into the engine?
Maybe a seal leaking fuel into the engine?
whitetiger
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It does not matter if they are OEM injectors, reman injectors, or injectors that fell off the back of a truck, they must be registered to the ECU. There is no way to get around it; it must be done using Diagmaster.
My reply may not include this tractor but a failing mechanical lift pump diaphragm has filled many sumps with fuel.
Dave
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curious so I checked, L3901 has an electric pump...... so mystery not solved yet...unless there's a 'passage' in the injector pump that allows fuel into the oil ??
grr. looked at a few more parts pages...seems there's a mechanical pump as well !
grr. looked at a few more parts pages...seems there's a mechanical pump as well !
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whitetiger
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Are you sure it is diesel fuel in the crankcase? Check your hydraulic oil level as you may have a failed seal in your hydraulic pump.