About a year ago I found diesel fuel in the crankcase but have not been able to find how it got in there.  Can someone tell me what I need to look for I finally have some time to work on it.  The S/N is 17A16035.

There is an O-Ring located between the fuel filter housing and the injector housing that goes bad. There are several past threads that discuss this problem. I had the problem with my D4 7U a few years ago. I will try to find the part number for the O-ring or some one may get it to you before I do. Try using the search tool. There is a lot of info on this problem. I believe that the seal is a 8B4967 but am not certain. I do not have any info on the D7.  There are two seals , one on the fuel tower side and one on the governor side. I changes both while I had it apart. The old ones will not look like O-rings at all because they come out very much out of shape. There should be pictures on some of the old posts. The D7 may also have other seals that I am not aware of. I have only had the problem with my D4 so hopefully some one familiar with the D7 can help. I seem to recall a post here not to long ago about the fuel transfer pump on a D7 causing the same issue? Hope I am not leading you in the wrong direction.

Bruce

check the transfer pump and replace the seals as mentioned on the injection pump. its not a expensive fix and will save the engine.

Old Magnet can you give me some advice?

Most likely culprit is a failed o-ring seal for the fuel gallery connection between the injection pump and filter housing. Part # 8B4967 (trade size -318). Requires removal of injection pump to replace. If the transfer pump seals were leaking it would show up as flow/dripping from the tell tale line that drains the cavity between the two pump seals.

Old Magnet can I remove the injection pump from the filter housing without removing the entire governor, filter housing and injection pump. Looks like there are a couple of bolts on the engine side of the injection pump that might be tricky to get out. can the injection pump be put back out of time or is it fool proof? I think all this fuel got into the crankcase when the tractor was setting for several months without being used. I want to get this fuel leak stopped and then try to start the diesel engine to see if it will still run ok before deciding what to do next which would be an engine overhaul.

If it was running when you stopped it should still be OK.
I check oil at shut off as the engine idles in cool down. Found more oil than the day before. Changed the oil, it as I was planting time and really needed it. After 6 hours looked and over full again. Took the chance and drove it a hour to put it in the yard. Payed a friend for day with his Cat to finish. At this point it was leaking without being running.

Has been 5 years (? time fly's could be more ) still running 50 to 100 hours a year. But I also have the remains of one that a guy tried to get just one more day out of that will never run again.

On the 9u D6's you cannot get it out of time. It all came off together. But a D7 could be different.

As I stated you only need to remove the injection pump. Pump timing is by offset tang at the coupling, you can't get it out of time.

I’m reviving an older post here because my 17A just filled the crankcase with diesel. What brought the issue to light was that oil was spewing from the front crankshaft seal. We replaced the seal and then cleaned out the crankcase vent which was pretty plugged up. We theorized that since the engine was tired and had a lot of blowby, the blowby had nowhere to go and blew out the front seal. The confusing part was that the old seal didn’t look bad when we pulled it.  With the new one installed, I pressure washed off all the oil that had splashed onto the radiator. Fired it up and decided to pull the dipstick and to my surprise it was way overfull. So I got a drain pan in place and pulled the plug, and much to my surprise, instead of having the usual nice and tight flowing stream of oil going directly into the drain pan, I ended up having a rush of oily diesel spewing every which direction but into the drain pan. Haha….I picked up the pan to drain it into my waste oil drum and the gravel immediately under the pan was the only dry spot there. Ended up throwing my diesel/oil soaked shirt into the trash. 

I’m guessing the culprit is most likely the 8B4967 o-ring. In re-reading these older posts, I see OldMagnet make mention of another possible culprit being the seals in the fuel transfer pump. To clarify, are the seals being referred to the two 5M6038’s that it appears would require full disassembly of the pump? Or is it the 7B305 on the drive gear side that we’re after? Or are we talking all three to be sure?

Thanks!
-Nick

It has been a while since I worked on a 17A but my bet is the O ring on the injection pump and housing is the culprit. If the transfer pump is seeping and the lines are clear there should be a drip from the bottom of the transfer pump if it is leaking. That being said the drip line could be plugged. Getting as much fuel as you have in the crankcase means it is probably the O ring on the pump housing.
If you are working on the transfer pump, replace all the seals and save yourself some work later on. I'd start with the O ring.