How to Fix JD 430 With Leaks on Top of Injector Pump

[Suburban Plowboy]

My 430 managed to develop a new problem, and I made it worse.

There are three rigid fuel lines going into the top of the injector pump on the port side of the engine. The center line, part number AM876210, was slowly dripping diesel where it went into the thing it goes into, which may be a delivery valve spring holder. I found a picture that shows an O-ring under this holder. Maybe it's loose or screwed up.

It is not possible to tighten the hex fitting on this line without removing another fuel line, because they are in the way.

I put a 17mm wrench on the fuel line fitting toward the front of the engine and began loosening. I noticed it was not getting much looser. Then I saw that the paint was flaking off. I realized I was twisting the line.

I tightened it back up, and now I have two leaking fuel fittings instead of one.

How is it possible to remove and replace these fittings without destroying anything?

I am going to have to spend $50 to get replacements for the lines on the front and in the middle. Can I leave the rear line alone?

Will post a photo from my tractor and an image someone posted of the parts on top of the pump. I probably have an O-ring that will fit.

 

[thepumpguysc]

You use the “double wrench” method..
Hold the delivery valve holder with one wrench and use another to loosen the line.. once u break the seal on the line nut, go to the other end and loosen the line at the injector..& remove the lines as u go.. keep them in order..
There IS an oring and a copper delivery valve gasket that will need replacing..
AND.. u MUST TORQUE THE HOLDER TO 35 inlbs.!!!
All this is do-able with the pump in place but much easier if it’s on the work bench, in a vise..
Good luck..
BTW.. u have to use the manufacturers parts.. orings and dv gskts.. or you’ll probably end up doing it TWICE..
Yanmar makes the parts but u can probably get them at JD for 3 x the cost..

 

[Suburban Plowboy]

That really helps. Thanks. Do you have any idea what the part numbers are for the O-rings and gaskets? They aren't even listed in JD diagrams.

 

[Suburban Plowboy]

I found something John Deere claims is a gasket, but it looks like a copper crush washer. The part number is CH16901. I can't find any reference to an O-ring on John Deere's site.

The O-rings are nitrile, and I have two big kits of nitrile rings.

 

[Suburban Plowboy]

I found Yanmar part numbers and a Yanmar manual, which I will upload. This is the Yanmar injection manual for the 3-cylinder 20-horsepower engine on the John Deere 430, with Yanmar engine 3TNA72UJ.

The O-ring is 124550-51370. The copper washer (delivery valve seat packing) is 124550-51350.

 

[Suburban Plowboy]

You use the “double wrench” method..
Hold the delivery valve holder with one wrench and use another to loosen the line.. once u break the seal on the line nut, go to the other end and loosen the line at the injector..& remove the lines as u go.. keep them in order..
There IS an oring and a copper delivery valve gasket that will need replacing..
AND.. u MUST TORQUE THE HOLDER TO 35 inlbs.!!!
All this is do-able with the pump in place but much easier if it’s on the work bench, in a vise..
Good luck..
BTW.. u have to use the manufacturers parts.. orings and dv gskts.. or you’ll probably end up doing it TWICE..
Yanmar makes the parts but u can probably get them at JD for 3 x the cost..

I got an email from you saying the parts numbers are wrong. Where can I get the right numbers?

 

[Suburban Plowboy]

Does anyone here know if I need gaskets or whatever to hook up the other side of the fuel lines?

 

[arto98607]

I got an email from you saying the parts numbers are wrong. Where can I get the right numbers?

You could start with John Deere website and your tractor model number - maybe that will help?

John Deere Parts Catalog

 

[Suburban Plowboy]

Thanks. I went there before I came here. That site is a real mess. I guess I could call them, but it's an old Yanmar engine.

 

[Suburban Plowboy]

Someone gave me JD part numbers.

Gasket/washer: M87846
O-ring: M87979

Much easier to find than Yanmar parts. They are cheap at Green Farm Parts.

I still don't know what to put on the other ends of the fuel lines. I would guess it's the same parts, since the fittings look the same.