Oil Level Extremely High

[BStone]

I have a L4600HST. Tractor is running but only at low RPM. Linkages are working. Tractor will just not respond to throttle. More alarming is the fact that the crankcase is overfull. I drained around 4 quarts of very thin oil to bring the dip stick level to the mid range on the stick. I have heard that the fuel pump diaphragm may be the issue. I understand how this would explain the high oil level as diesel can enter crankcase. My question is, "Would this also explain the tractor running at low RPM but not responding to increase throttle?
My gut says it might, but wondered if anyone could confirm.

Also, this engine "ran away" with me about 3 weeks, (12 hours run time) ago. Was running rough before it ran away, then ran fine until yesterday.

 

[Cglaza]

I would not run that engine anymore until you figure out where the Diesel is coming from. Diesel doesn't not have the proper lubricating properties for your engine and you may damage it further requiring an engine rebuild. But you are on the right thinking of where the Diesel would be coming from. Your injection pump is where the Diesel is more than likely getting into your engine. Being that you had a runaway and now no control, I would be looking at the injection pump really hard.

Sent from my moto z4 using Tapatalk

 

[CapnDean]

yes : It sounds to me like you are "making oil" - DO NOT RUN IT. I suspect strongly that your runaway problem is directly related to this. You are correct that the injector pump is a likely culprit. There are other things that can cause this but the seals in your injector pump are the most likely. A stuck open injector can allow waaay too much fuel to be dumped on a cylinder but you would see that in the exhaust. Usually I wouldn't start out with "remove the injection pump" but in this case I would have it re-sealed first most.

 

[Dave_eng]

There are several variants of the L4600 so check carefully to see if I have the correct engine mounted fuel pump.

Check attached parts photo. It shows a fuel pump attached to the side of the injection pump.

This "lift pump," style of pump is known to have diaphragm failures which can lead to fuel entering the engine. It could also be failing to deliver fuel to the engine in adequate amounts to run properly.

Agree with advice not to run engine with diesel mixed with oil.

Dave

 

[thepumpguysc]

Dave is on the right path.. IF the lift/supply pump is leaking into the crank case, its not delivering the correct amount of fuel pressure to the injection pump..
hence, no throttle response..
Either take it off & put AIR pressure to the inlet side & block off the outlet side w/ your finger & dunk it in some water & SEE if u have bubbles out of the engine side..
Its either that or something went wonky w/ your inj. pump..
Good luck

 

[PoTreeBoy]

Sounds like fuel in oil, but are you sure it's not hydraulic? How's your hydraulic level?
I should start out by saying I know nothing specific about your tractor.
You may have gotten a high enough oil level that it blew oil out of the crankcase vent into the intake. That provided the fuel to cause the runaway. How long did it overrev and how did you stop it?
So replacing the lift pump will fix that problem, but the question is what else might have been damaged? It was running rough before. Was that because of oil carryover or something else? I'm not sure how far I'd go if it was mine, so I can't advise you. At the very least I'd clean out the crankcase vent tube (assuming it has one). I'm sure others will have advice.