D6 9u Fuel in the oil

I just worked on a neighbors 9U that was getting fuel into the crankcase last month. The culprit was the O ring between the fuel injection pump and the filter tower. There is also an identical O ring at the other end of the fuel rail between the injection pump and the governor that you may as well replace while you are there. Its not a very hard job, the injection pump drive can only be assembled one way (offset drive tang). I got the parts ( two O rings and two gaskets) from Cat for less than $35 if I remember right. The fuel pump is heavy so be prepared for that. Also there are a couple of bolts behind the fuel pump that are fun to get at, just get an assortment of u-joint sockets and extensions and be patient, you'll get em. Hope this helps.

Good luck

Bruce P

Sorry for the double info, ccjersey types faster than I do! lol

Bruce P

yes, most common source.
Take that funny shaped cover off the filter tower and you can see the leak source.

Raymond, I changed the "O" ring on the ferrule on my 7U after removing the injector housing late last year. It is inexpensive to do and not too time consuming. The housing is heavy and I lifted it onto the track and fixed it there. The nut in the back is tough to get to. I did pressure wash the crud out from behind before working on it and that helps a lot to see what you are doing. The "O" ring is a fat one and crushes down when you tighten the bolts while installing the housing. I did change the lip seal since I had it apart. That keeps the fuel out of the injector housing.