I have a friends 2008 L48. He couldnt get her started. Asked me to look at it for him. He had recently replaced fuel filter and lift pump. i bled the fuel system first and checked all relays and lever switches. All seem to be in good working order. She turns over fine and seems to have good compression but wont fire. After scratching my head for a bit and recharging the battery i checked the oil and realized there is fuel in the oil tank. Quite a bit actually. Definitly fuel and not hydro fluid. Could there be something wrong with the injector pump? It hasnt been serviced yet but the injectors themselves were serviced.
fuel in oil pan
- Thread starter kyle b.
- Start date
North Idaho Wolfman
Moderator
Staff member
Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
How do you know there is fuel in the oil?
How far overfilled is it?
And you wouldn't be able to tell the difference between hydraulic oil and motor oil in the motor, it's not like they stay separated, same with fuel, it will simply just blend with the motor oil.
If it does have fuel is probably from a bad lift pump, that's the most common place for it to came from, it's very very rare that the injection pump leaks fuel into the oil.
If he changed out fuel system components and didn't bleed the system, you're probably not starting because it needs the line bleed all the way to the injectors.
Crack all the lines at the injectors, set the throttle to high, crank till you get clean bubble free fuel out the injector lines.
well it smells like fuel and not hydro fluid and the little bit of fuel that was in the tank is now almost gone. The hydro fluid is still right at full with no signs of loss. there seems to be quite a bit of fluid in the oil pan. Almost enough to come out of the dipstick tube. Guessing at least a gallon or so too much. the lift pump is brand new with no signs of damage. I did bleed the lines all the way to injectors. Have yet to pull injectors and inspect them but they were pulled by a Kubota tech and inspected to my knowledge. Thinking either an injector nozzle is off or damaged or a seal is bad in the injector pump.
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
I would go ahead and drain the oil out and refill with oil. Then see if it gets over full again.
You may want to remove the injectors and see if one is flooding the cylinder and getting into the oil. Rearrange the line so the injector can be attached outside the engine. Reconnect the injector to the line and bleed the line to the injector and use a cardboard piece to see how the injector sprays. Don’t get your hand close to the spray since it will be high pressure spray. (But you probably know that already)
Sent from my iPad using Tapatalk
You may want to remove the injectors and see if one is flooding the cylinder and getting into the oil. Rearrange the line so the injector can be attached outside the engine. Reconnect the injector to the line and bleed the line to the injector and use a cardboard piece to see how the injector sprays. Don’t get your hand close to the spray since it will be high pressure spray. (But you probably know that already)
Sent from my iPad using Tapatalk
Hey thanks Russell. Pulling the injectors was next on my list in hopes of not pulling the pump....which looks to be one heck of a project. LOL. Guess its a good time to pull and inspect/test the glowplugs as well. Definitely a good idea with the cardboard too. Appreciate it brother.
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
If you have to loosen the lines at the injector pump, be sure to hold the larger hex with a wrench so it doesn't move. There is some mechanism there that larger nut holds in place.
Sent from my iPad using Tapatalk
Sent from my iPad using Tapatalk
A failed lift pump will sometimes fill the crankcase with fuel so don't blame the injectors quite yet.
Do you know why the lift pump was replaced? Could the fuel in the oil have been in the oil at that time? it may be as Russell K suggested. Change the oil and see what happens. That problem might already be fixed. Not starting might be a separate issue. With all that fuel in the oil, not starting might have been a good thing.
I believe the lift pump was replaced hoping it was the starting issue which is working properly and does not seem to be leaking internally. Waiting on the funds for oil and filter replacement from owner. Also checking on gasket and seal kit for injector pump. Having a tuff time finding the exact injector pump part number to ensure proper kit is ordered.
North Idaho Wolfman
Moderator
Staff member
Lifetime Member
Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
There is no gasket or seal kit that will fix it if it's leaking fuel out the bottom of the pump (the only path to oil).
As the seal from the pumps piston to the fuel is steel to steel.
Unless you've rebuilt quite a few pump I wouldn't recommend you mess with it, as just removing the delivery valves and not installing them perfectly can damage the pump beyond repair.
Send it to someone that can rebuild the pump with the proper test equipment.
Also if you remove the pump and send it in to be tested, remove all of the shims under the pump and do not lose them as that is how the timing is set.
It is very very very unlikely that fuel is leaking out the bottom of the injection pump, I've worked on countless units and have yet to find one leaking.
And you can throw all this information out into the wind if someone has worked on the injection pump before you got to it.
Edit: Correction: one pump was leaking, it had water in the pump and froze and cracked the case of the pump.
Last edited:
Thank you wolf man. It appears no one has touched the pump yet. I have not either. Working on draining oil and replacing filters. Going to recheck lift pump and bleed the system again. Be back tonight and post progress. Thanks again wolfman.
i had a bad lift pump, did the same thing one time, i sent my oil off an came back fuel in oil....