b7100 injector pump leaking

[Steve NC]

Hope everyone is having a great holiday season. I started up my tractor today and noticed a leak on my injector pump. I couldn't find anything loose. The fuel leak appears to be coming from between the big nut and the top of the injector pump itself. I cleaned off the entire injector pump and all three lines with brake cleaner and then blew the area off with compressed air. I started up the tractor and this was the area of the fuel leak. My manual doesn't give me much detail about the injector pump itself. I saw in the parts book that it lists an o-ring and a gasket below this nut and was wondering if anyone had worked on this problem before and knew if it was as simple as backing off this fitting after removing the fuel line to change the o-ring and maybe the gasket or it required more work with the pump itself.

 

[85Hokie]

you my friend have a bad O ring!

Easy to replace - getting the O ring is not $$ either - the shipping kinda sucks on a .99 cent part! However, if you can get the specific size, you could go down to NAPA or anyone like that and get one. Get 1/2 dozen while you are there too!

I bought an entire O ring set at Northern Tool (Harbor Freight has them too) like 10 bucks.

Now, I'll tell you this, getting that mofo off can be fun! If you are dealing with the middle one, it is a grade A beeeaaauuuch! Unless of COURSE you take the first one out and then get to the middle one. ( I chose the hard way!)

Here is what I did - I took a crappy ol 19mm wrench, cut a slot in it and allowed it to slide down the top.....after a lot of torque I snapped that 19 like a candy cane! Sooo..... I ground down the open end and allowed it to sit on the nut as I held the nut below with another wrench and then gave the 19 a couple of taps. YOU must take the line off first! THEN get the nut on top of the pump. DO not try to loosen the bottom nut only.

After taking the line off completely - you can get another box end down on top - I had to grind the side walls off the open end wrench to do it.

Once the nut is free - be careful to twist it off slowly, expect a little tension under it, and then once free - slide it up and pull out. The O ring will be there....and flat at day old beer too.

There are other parts that could come out, a spring and/or small ball ....so I have been told!

Pull the old O ring off, replace it, a little lube and retorque everything (except the top line where it goes into the injector.....)

If your machine has a decomp lever (it should at that age) - use it as you spin the engine over with the the throttle wide open, it will spit after a while and then will pump diesel down your injector. Tighten top nut and she should fire up and no leaks!

What I left out - someone will correct!

 

[D2Cat]

I'd also suggest doing all three since you're there.

O-rings aren't quite as critical as some other parts, but if you're near a dealer just buy the correct ones there. They're less then a $, and they're the correct metric O-ring.

I would also suggest to have the O-rings when you start dis-assembly. That way you can remove, install and be done. There are a couple of small parts in there you don't want to misplace, move or turn upside down!

Have a nice clean floor, or at least a clean piece of cardboard under you engine as you work on it. It sure makes it easier to find boo boo's!

 

[D2Cat]

85Hokie,

"Now, I'll tell you this, getting that mofo off can be fun! If you are dealing with the middle one, it is a grade A beeeaaauuuch! Unless of COURSE you take the first one out and then get to the middle one. ( I chose the hard way!)"

What happens if you need the middle one loose, but you start with the third one? Will that screw up the process?

 

[85Hokie]

85Hokie,

"Now, I'll tell you this, getting that mofo off can be fun! If you are dealing with the middle one, it is a grade A beeeaaauuuch! Unless of COURSE you take the first one out and then get to the middle one. ( I chose the hard way!)"

What happens if you need the middle one loose, but you start with the third one? Will that screw up the process?

you cant start with the 3rd one......that one is worse than the middle one!!!

 

[D2Cat]

I know it's getting late, but which one is the first one, then?

 

[85Hokie]

I know it's getting late, but which one is the first one, then?

Ok.....I am really am LOL !!!

The first one is the one that the wrench touches first?????

IF I remember correctly .....YOU TOLD ME The easy way......and I f#@$ed that all up!!! I broke a cheap POS wrench and invented a couple of new words!

 

[Steve NC]

Thanks guys! I was hoping it would be that simple but after looking at the parts break down I wasn't sure. I was just wondering about the "boo boos" I might encounter. Hokie, it is the one closest to the radiator but I plan to do like Cat mentioned and replace all 3 provided nothing else flew out of the pump. I am preparing a parts order for next week. I was getting ready to take advantage of the 70 degree weather we are getting right now and repaint the tractor and order new decals along with a seal for the front axle and some more o-rings for the lift. Considering this tractor has seen its share of use and abuse im really surprised in its over all condition. I couldn't be more pleased with the way it has performed this year.

 

[D2Cat]

Steve, there is a little "check valve" that sets in there (looks like a very small copper T), and a small spring. They won't jump out at you!! They will stay where they are when you remove the line. Just be aware they are there and don't move them.

That is why I suggested, have the replacement O-rings right there and just put them on and re-assemble.

Be sure to clean the area before you begin to work around the IP. Keep each valve covered as you work on the next one. You will need to remove all three lines, then re-assemble in the reverse order so your wrenches fit between each valve again!

 

[M3Stevie]

I just did this job myself on a B7100 I picked up a few weeks ago. The Delivery Valve Holder closest to the firewall was loose as the PO tried bleeding the line at the pump and I had no way of tightening it with everything assembled. I just pulled the fuel lines then the Delivery Valve Holders and changed all 3 O Rings while it was apart. I also blasted the fuel lines with brake cleaners and blew them out with air. The PO ran it out of fuel and could never get it restarted so I did this job after replacing all the rubber lines up to the injector pump and before I got it running. It was more of a trouble shooting and clean up exercise.