Getting my D4 7U 9689 up and running, I had to pull the governor to get the starting pinion out.  For any concerned about messing with a governor, it was an easy removal, once I saw that I had to remove the lower bolt holding the governor spring, I could then unbolt the lever that links to the injection pump.  I found this to be an efficient design.   As I was in that far, I figured, might as well pull the injection pump and replace the 2 o-rings 8B4967 and the cam seal 4B4865.  As a side note, I used a 12” C-clamp to help pull/press in the o-ring at the end of the fuel galley, its tight, but with some dull screwdrivers, I had it pulled/pressed in, in about 10 minutes.  Glad I made the effort to do the work, what I found was the front o-ring was leaking, the end cap o-ring was fine, the cam seal was completely worn.  Sorry for the long play-by-play, but I found the fuel galley had been rusting, and it had accumulated a good amount of rust at the 4th pump.  I removed the pumps, and carefully honed the fuel galley, clearing it all out well with spray  brake and carb cleaner.  The 4th ferrule was clogged, I got that cleared and polished.  Part of the ferrule had corroded, but I don’t think I should try to mess with it—thoughts, difficult to pull or press in?  What would you suggest I do on the injector line, I figured I would try to blow it out, to make sure it is clear?  Also, anything I can/should do for the 4th injector, I believe chances are good that it has crud in it.  Thoughts/advice?  Thanks.

Hi OBR,
I would leave the ferrule as it will likely update to a different design that suits the later forged body pumps that do not have the bleed screws.

As a by the way---
they are tight in the housing and the update ones are even tighter and hard and so shattered when we tried to fit or pull damaged ones at the Dealer.
The update ones have an orientation and installed height that must be followed.
Cheers,
Eddie B.

Thanks Eddie B for the info on the ferrule...perhaps in another 50 years or so, it will need to be replaced by a machine shop. I'm going to replace the ferrule o-rings and button it all up.

Thanks Neil for the info, sounds like they were about in the same rusted condition, I really don't think #4 was getting much fuel, if any. If you could provide the model filter/separator you installed, I'm thinking that needs to be on my list. I'm also going to pull the 3 filters and see about cleaning out the fuel tower, any tips on that process? Best.

any aftermarket water separator will work just get one with a plastic or metal bowl instead of glass as glass is a bit too fragile for crawler tractors.
and remember the lucas/cav style will leak if overtightened as the seals move out of place. i have a parker-racor type unit on my machine.
the filter tower simply drain it wipe it out and rinse clean with diesel and of course fit new filter elements.

Great, thanks all for the replies.

Hello, I have a D4 7U and I have been trying for days to get the pony start pinion out. Manual says just pull the govenor housing cover. But this is just not enough. It seems almost impossible to pull the back side bolt on the govenor housing. I have the flywheel clutch out so I was thinking on pulling the flywheel but I dont know if that is going to work either. Did you actually pull the whole injection pump to get the pinion out? Anyone have any suggestions? Thanks

rsilva11, This is how I got out my D2 pinion. As long as you have removed the pony/donkey motor off the top of bell housing and have the pinion engaged (shortened length as it would be to start diesel motor), it should come out, from memory a slight roll away from main engine and it should come out, heavy little sucker if it lands on a finger on the way out, yes its tight to get in and out, I took side cover off that has handle in it as well (Pinion must be shortened or will not come out) I hope this helps