Kubota 1J770-50605 Common Rail Assembly for V2607-CR / V3307-CR (Genuine)

Genuine Kubota common rail assembly, part number 1J770-50605, Kubota catalog description RAIL,ASSY. This is the high pressure accumulator rail for Kubota’s V2607-CR common rail diesel: it holds fuel at injection pressure between the Denso HP3 type supply pump and the injectors, and it appears as catalog section 548000 COMMON RAIL in the Kubota parts books. We verified 1J770-50605 as the current genuine number on the OEM diagrams for both the KX057-4 excavator (engine designation V2607-CR-E4-BH1/2) and the SSV65 skid steer. Kubota supplies it as a complete rail assembly with its rail mounted pressure hardware; the injection pipes, hollow screw and pipe stay shown on the same diagram are separate part numbers.

Valley Fuel Injection & Turbo is an authorized Kubota dealer and a diesel fuel injection specialty shop in Woodland, California. We are not a box shipper: we handle common rail system repair on the bench every week, we supply the full genuine Kubota engine parts picture around this rail, and we verify the part against your engine serial number before anything ships.

Application & Fitment

Confirmed applications for 1J770-50605, taken from Kubota OEM parts diagrams:

• Kubota V2607-CR-E4: KX057-4 compact excavator (diagram designation V2607-CR-E4-BH1/2)
• Kubota V2607-CR-TE4: SSV65 skid steer loader; the SVL65-2 compact track loader runs the same engine and its Kubota catalog carries the same 548000 Common Rail assembly
• Kubota V3307-CR-TE4: the V3307-CR shares this rail assembly with the V2607-CR

Dealer and aftermarket listings for this rail and its direct predecessors also reference the U55-4 and U55-5 excavators, the R530 series wheel loaders and the SVL75-2C, which is consistent with the shared V2607/V3307 common rail platform, but we have not verified those machines against an OEM diagram ourselves. If your machine is not listed above, do not guess: give us the engine model and serial number and we will confirm the exact current Kubota number for your unit.

One caution from our parts counter: do not confuse this rail with the 1J574-506xx or 1J508-506xx rail assemblies. Those fit the larger V3800 engine used in M series tractors and SVL90-2/SVL95-2 track loaders. The prefixes look similar; the rails are not interchangeable.

Cross-Reference Part Numbers

• Kubota supersession chain: 1J770-50600, 1J770-50603 and 1J770-50604 are all replaced by the current 1J770-50605. If the tag on your old rail shows any of those numbers, this is the correct genuine replacement.
• Caterpillar 436-1092: cross for the earlier 1J770-50600 / 1J770-50603 rail on the CAT C3.3B, the Caterpillar build of the Kubota V3307-CR.

Denso reference numbers for this rail circulate on aftermarket listings, but we have not verified them against Denso literature, so we do not publish them. Read us the numbers on your old rail and we will cross them properly.

Frequently Asked Questions

Does 1J770-50605 replace 1J770-50600, 1J770-50603 and 1J770-50604?

Yes. Kubota has superseded that entire chain to 1J770-50605, so the current number is the correct genuine replacement for all of the earlier rail numbers on these engines.

How do I make sure this rail fits my machine?

Have your engine model and engine serial number ready when you call. The V2607-CR and V3307-CR share this assembly, but Kubota fuel system parts can change by serial range, so we confirm the current number for your exact unit before we quote. That is standard procedure on every genuine Kubota fuel system part we sell.

My supply pump failed. Should the rail be replaced at the same time?

Often, yes. A failing supply pump can push metal debris downstream through the rail, injection pipes and injectors, and a contaminated rail will take out new components. We can advise on cleaning versus replacement, test your injectors through our mail-in rebuild service, and quote the related genuine parts for this system in one call, including the 1J770-50504 supply pump, the 1J500-50550 SCV kit and serial-correct injectors.

Why Buy From Valley Fuel Injection

Valley Fuel Injection & Turbo has specialized in diesel fuel injection since 1993 and is an authorized Kubota dealer. That combination matters on common rail work: we sell the genuine part and we also diagnose and repair these systems every day in our fuel injection shop. We check supersessions and serial breaks before shipping, we can package the rail with the matching Kubota pump, injectors and sensors, and if your symptoms point to diagnosis rather than parts, we will tell you that straight.

Pricing & Availability

This genuine Kubota rail assembly is sold by phone so fitment gets verified on every order. Call 530-668-0818 or contact us online for current pricing and availability. Please have your engine model and engine serial number ready and we will confirm 1J770-50605 is the correct current number for your machine before we quote it.