MD Crankcase Dilution

Ok here goes. I HAD HUCKSTORF DIESEL OF FRANKLIN, WI REBUILD THE LIFT PUMP RIGHT AFTER I GOT THE TRACTOR bc it was diluting the oil in the crankcase. IT WAS NOT DILUTING THE OIL WHEN SITTING, but everybody said it was the lift pump anyhow. I finally said the heck with it and got it done. I replaced both fuel filters and sedement bowl gasket at that time. I have now owned it for five years and haven't done much more than start it once a year.

Now that I have played with it the fuel bowl leaks down sometimes. I would guess that could dilute the oil, but it only leaks about an inch and never gets worse. I turn the fuel off when not in use.
Could I have installed the sedement bowl or fuel filter gaskets wrong?
Could I have installed the lift pump or seal wrong and now it has a problem?
Why is it leaking down when sitting?
When I bleed the injectors two and three do not pulse just pee out fuel. Could this be the cause for oil dilution when running?
Can you put some sort of potion in the fuel to clean them or do they have to be rebuilt? Where should I send them?

really sounds like the injectors are at fault here. does the engine smoke really bad, or exssive blow by ? one thing that imconfused on is you say your getting diesel in the engine crankcase or in the bottom of the injector pump ? id imagine that it would be pretty hard to have diesel pour into the crankcase. unless... the injector pump is filling up with fuel and the front pump seal is bad cause fuel to leak into the crankcase that way. if this is the case then the seals in the pump are bad, leaking fuel into the oil for the pump.

Andrew

Like Andrew said, in order for fuel to get into engine crankcase from any part of the filter or pump system, it would first of all have to over fill the pump sump with fuel and go in from there. If injection nozzles are the problem it won't be running very well and if compression same thing. I have seen engines literally fill crankcase when one cyl was missfiring, however, this is ordinarilly on a 6 cyl combine where the opertor is not in tune as much as to how the engine sounds.

No, the inj pump does not fill with diesel.
Yes, the engine doesn't run awesome that's why I don't run it much.
Yes, there is a fair amount of smoke, but not like my pickup with the chip turned up
Whenever I pose this question to others they always say lift pump, but like you guys said all the symptoms aren't there for lift pump. I appreciate you looking past the "that is always the problem" solution!
The engine does knock for the first little bit when you switch over. Nothing outragous, but it is noticable. Ask me more questions! I don't really know enough to tell you everything you need. Are injectors something you can rebuild yourself or is that something that must be sent out?

Ok, thats good to know that the pump is not leaking fuel directly into the crank. I would suspect what you thought then with the injectors. When i had my injectors rebuilt two of them were near pluged solid and the 3 of them were opening at way to low of a pressure. Thus just "dumping" fuel into the cylinders, not a fine mist like it should be. When i had them done it cost around 275 to have all 4 done. You unfortunatly can not test them on your own beacuse there are speical tools required to test pressure, flow and so forth. The only question i have to lift pump is how much pressure you are getting out of it? This would be the gauge on the side of the pump. The gague just shows a red and white range, remove that gauge and install a regular pressure gauge with number 0-100lbs will work fine. you should have at least 40 lbs of pressure.

Andrew

(quoted from post at 13:15:48 12/22/09) Ok, thats good to know that the pump is not leaking fuel directly into the crank. I would suspect what you thought then with the injectors. When i had my injectors rebuilt two of them were near pluged solid and the 3 of them were opening at way to low of a pressure. Thus just "dumping" fuel into the cylinders, not a fine mist like it should be. When i had them done it cost around 275 to have all 4 done. You unfortunatly can not test them on your own beacuse there are speical tools required to test pressure, flow and so forth. The only question i have to lift pump is how much pressure you are getting out of it? This would be the gauge on the side of the pump. The gague just shows a red and white range, remove that gauge and install a regular pressure gauge with number 0-100lbs will work fine. you should have at least 40 lbs of pressure.

Andrew

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A gauge with white and red on it!?! Mine is yellow with a bunch of oil I will get a regular gauge and throw it in there to quantify the pressure.

Where did you send your injectors?

EDIT - Any idea on the fuel bowl leaking down? Just a poor gasket fit? Nothing leaks when it is running and the bowl fills up to capacity.

yes a gauge that works will sure help I got mine done at a local diesel injector repair shop here in CT. I would think that any good diesel repair shop would be able to service them. They are not complex or confusing or unique like say the pump its self is.

Andrew

I agree with the other guys it probually is a injector issue but before I pulled them out and had them rebuilt. I would check the injection pump vent tube see if that is plugged. If it is it could return fuel aslo. I would have the injectors pattern tested and that almost any tractor or engine shop can do. See if they are bad of if you are chasing the wrong thing. I have rebuilt my MD completly now and have 2 others that are just in need of restore. I have my WD6 (same except for standard tread model). It has 1500 original hours on it. Just thought i would throw in my 2 cents. Good Luck.

(quoted from post at 16:43:17 12/23/09) I agree with the other guys it probually is a injector issue but before I pulled them out and had them rebuilt. I would check the injection pump vent tube see if that is plugged. If it is it could return fuel aslo. I would have the injectors pattern tested and that almost any tractor or engine shop can do. See if they are bad of if you are chasing the wrong thing. I have rebuilt my MD completly now and have 2 others that are just in need of restore. I have my WD6 (same except for standard tread model). It has 1500 original hours on it. Just thought i would throw in my 2 cents. Good Luck.

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I appreciate the .02! I never thought about the vent tube. Like most originals it was cacked with mud and oil so that could be a possibility. It is good the hear from somebody who has experience.

Hey was just wondering what you found on your md? Wondering what you have found is wrong with it maybe. Send my a email when you get a chance I love to here about these old gas overs and well try to help you anyway I can. Thanks