Injection Pump Leak

[Stob]

L2550- I'm seeing a leak on top of the injection pump. Looking at the parts diagram, the "holder delivery valve" appears to screw into the pump top, then the injection lines connect to the top of this holder. The leak appears to be where this holder screws into the pump. I have not attempted to tighten any of them, wanted to ask before putting a wrench to them. During use, it leaks enough where fuel is easily seen dripping on the ground. Not a lot of fuel, no stream or anything, but I would like to stop the leak. Those holders are close together, I think I would have to take the lines off to get a deep socket down from the top. Do these leak as a common thing? I assume they should be tight into the pump?

 

[85Hokie]

Not familiar with your engine - however, most have a crush washer or O ring that will need to be replaced to stop the leak.

OVER tightening the nut can lead to real bad things! SO unless it is loose - I would not place the ol' snug and half on it !!!

If not mistaken - 19mm on the nut, make sure the top is loosened first, hold the bottom one still as you loosen - I would remove the top connection completely and then place a socket or box end on the the bottom nut.

IS it the middle one or one on the end? Middle can be fun to deal with!!!

 

[Stob]

most have a crush washer or O ring that will need to be replaced to stop the leak.

You are right, the parts diagram does show an o-ring below the threads. I can't tell if it's the middle or rear line, that is where it's wet. The front looks OK.

The diagram also shows springs, if I replace o-rings, how much pressure do these springs have?

 

[85Hokie]

You are right, the parts diagram does show an o-ring below the threads. I can't tell if it's the middle or rear line, that is where it's wet. The front looks OK.

The diagram also shows springs, if I replace o-rings, how much pressure do these springs have?

I too was scared of stuff POPPING out, as I loosened the nut(s) I eased up carefully - nothing will pop up - just make sure the little stuff stays in place - you'll see what I am talking about - make sure you have a clean place to work and lube the oil ring a little when placing it back in.

To check to see which it is - clean and scrub everything with a little break cleaner and toothbrush - then fire her up (mine leaked without running) and then shine a flashlight into the area.

Since you are already getting ready to break it down - buy several O rings......hitting them all while you are there. About the time you fix one, MURPHYs law will kick in!!!!

ONCE - finished, bleed till bubble free at the top end.....and she'll make a mess once more - but after you clean that up - should be leak free!

 

[North Idaho Wolfman]

85Hokie covered it pretty well!
Think hospital clean!

Buy factory O-rings, they will be sized exactly right for it. P/N 15331-96760

 

[Stob]

Thanks guys. I'll get them ordered and wait for a decent day.

 

[1970cs]

If you are going that far, you might as well do the delivery valve washers. They have been known to cause part of leakage and slow start issues.

 

[Delmar]

Here's a link to a good thread on another forum that sounds like it addresses your issue. If you have the little pin in your plunger (talked about in the thread) be careful when disassembling.
http://www.tractorbynet.com/forums/kubota-owning-operating/345923-you-can-repair-leaky-fuel.html

 

[North Idaho Wolfman]

Here's a link to a good thread on another forum that sounds like it addresses your issue.

SORRY BUT NEGATIVE!!!!
I only read a very small portion of that thread, but that is the completely wrong way to take it apart.

The reason they put security Torx heads on the bolts is your not supposed to remove them!

That is also a different style of injection pump!

 

[Tooljunkie]

My approach is to clean area and dry it with compressed air, verify where leak is and then proceed with repair. One speck of dirt can cause other problems so the cleaner the better.

 

[kuboman]

The brass washer at the bottom is the critical one to change. It is where the leak occurs. The o-ring is to keep dirt and moisture out.

 

[Delmar]

Sorry. Didn't mean to muddy the waters by posting a link to the other thread.