diesel fuel in oil of my JD450b crawler

[RP]

My mechanic has replaced the fuel injectors, fuel pump and seals on the shaft of the fuel injection pump. Still getting diesel in the fuel. Any ideas? Thanks.

[NWJD fan]

Umbrella seals on the injection pump shaft can be finicky. Also make sure the surfaces the seals ride on are not rough or scored. Lift pump was replaced?

[jtrichard]

X2 on both..... About the only way raw fuel can get in oil pan

[RP]

Yes, the lift pump was replaced. My mechanics feels it might be those umbrella seals. Yea, they are tricky. Thanks.

[Les]

Well, I got the same problem on my 450B - fuel all the way up my dipstick! What I DON'T have is a mechanic! How do I go about replacing the umbrella seals on my pump myself, and where can I get the parts? Thanks for your help.

[Les]

By the way, I have fuel spraying from under my FIP on the external of the engine. Is that from the same issue, or do I have additional problems?

[NWJD fan]

A diesel fuel injection shop should be able to supply umbrella seals. Fuel spraying from the pump is something else, maybe a bad seal on the throttle shaft or loose bolt/bad crush seal on one of the injector lines would be my first guess. There are a few recent threads here with good info on removing and installing injection pump to access seals if you haven't done it before. If you don't have a service manual now is probably the time to get one.

[RP]

You might need to replace the Fuel Transfer Pump. It could be source of fuel getting in your engine too. About $50. Suggest you do it before you replace the umbrella seals. The umbrella seals are part number T11290. You need 2 of them. They are very tricky to replace. There are some timing lines that need to be found and kept in place for the Fuel Injection Pump. Also there are some special tools that can be helpful to put the umbrella seals in (Stanadyne). I had a mechanic do my work.

http://www.oshkoshequipment.com/product ... ation-tool

http://www.oshkoshequipment.com/product ... ation-tool

[Les]

Awesome! Thanks for the advice. I'll get to work as soon as I can get this guy back to the workshop.

[RP]

Again, my opinion, change the Fuel Transfer Pump first. It is easy compared to replacing the umbrella seals. After you do that check the oil for increased diesel in the fuel. (I replaced the oil in my dozer many times for accurate reading on diesel in oil.)

I think,(and I would like to hear from others), that at idle, that diesel fuel will seep past the umbrella seals if they are in fact the problem just due to the hydraulic pressure from the higher elevation of diesel fuel above the umbrella seals. I'm not sure.

[Les]

10-4. Got one ordered. Hope that's it. Also, it looks like that part # is no longer available (T11290). That have another set of seals with a different part number though. Not sure if those will fit.

[RP]

Here is website for JD parts. Also, they do carry some special tools, but not sure if they have what is necessary for the umbrella seals. They didn't return my email. I was able to borrow those 2 tools.

http://www.greenpartstore.com/

[RP]

Here is website for JD parts. Just type in "450b" where it asks for model.

http://jdpc.deere.com/jdpc/servlet/com. ... ervlet_Alt

[my74ls4]

Just replaced my umbrella seals after a FIP rebuild. I took a aluminum coke can and cut a 1" x 2" strip of aluminum. Wrapped it around the seals after lubing them with petroleum lube. Slid pump over aluminum and slid aluminum strip out. Slowly and carefully slide pump on the rest of the way. Worked perfect, no special tool needed.

[RP]

That is great idea. I was thinking (if I had to replace umbrella seals again) of modifying some small food tongs (like for hot dogs) to put those seals in. And a cigar container (expensive cigar) might have worked to slide those seals on.