Genuine Kubota Supply Pump 1J770-50504 for V2607-CR Common Rail Engines

Kubota part number 1J770-50504, factory description PUMP,ASSY(SUPPLY), is the genuine high pressure supply pump for the Kubota V2607-CR common rail diesel engine. This is a Denso HP3 type pump, the component that pressurizes fuel and feeds the common rail on Tier 4 Final V2607-CR-E4, V2607-CR-TE4, and V2607-CR-TIE4 engines. Kubota fits the same assembly to the V3307-CR-TE4, so this one current number serves both engine families across a long list of compact excavators, track loaders, skid steers, wheel loaders, and tractors.

When a supply pump goes down you typically see long cranking, hard starting, low rail pressure fault codes, power derate, or a machine that dies under load and refuses to restart. Valley Fuel Injection & Turbo in Woodland, California is an authorized Kubota dealer and a dedicated fuel injection shop that has been testing and rebuilding diesel pumps and injectors since 1993. We do not just box up a part number: we verify the current correct pump against your engine serial number before anything ships.

Application & Fitment

1J770-50504 appears in Kubota parts diagram section 526500 SUPPLY PUMP and is confirmed for these engines and machines:

• V2607-CR-E4: KX057-4 and U55-4 compact excavators
• V2607-CR-TE4 / V2607-CR-TIE4: SVL65-2 and SVL65-2C compact track loaders, SSV65 / SSV65C / SSV65P / SSV65PC skid steers, and the R530 wheel loader
• V3307-CR-TE4 (shared assembly): SVL75-2, SSV75, KX080-4S, and M6060 / M7060 tractors

Kubota dealer fitment listings also show this pump for the R540, R630, R640, KX057-5, KX080-4, KX080-4S2, KX080-5, U55-5, SVL75-3, M4-071HDC12, M6060HDC, and M7060HDC, and the same pump serves the CAT C3.3B engine built on the V3307-CR platform. Fitment on several models is serial number dependent, so have your engine model and serial number ready and we will confirm the exact application before quoting.

Cross-Reference Part Numbers

Kubota supersession: 1J770-50500, 1J770-50501, 1J770-50502, and 1J770-50503 have all been replaced by the current 1J770-50504. Any of those numbers on your old pump lead to this part.

Denso: 294000-1870, 294000-1871, 294000-1872, 294000-1873, 294000-1874 (HP3 series supply pumps).

Caterpillar: 436-1091 (C3.3B).

One important caution: pumps sold online as 1J730-51010, 1J730-51012, or 1J730-51013 “for KX057-4 and U55-4” are the mechanical injection pump for the earlier V2607-DI-E3 Tier 4 interim engine. They do not interchange with the common rail supply pump on this page. If you are not sure which engine you have, call us and we will sort it out from the serial number.

Frequently Asked Questions

How do I confirm 1J770-50504 fits my machine?

Give us your machine model and engine serial number. The V2607-CR and V3307-CR share this supply pump, and Kubota has revised the part several times, so serial verification is the only way to guarantee the current correct assembly. Call 530-668-0818 and we will check it against the factory parts system while you are on the phone.

My old pump is marked 1J770-50500 or 1J770-50503. Is this the right replacement?

Yes. Kubota superseded 1J770-50500, 1J770-50501, 1J770-50502, and 1J770-50503 into the current 1J770-50504, so you receive the latest revision of the genuine Denso built pump regardless of which earlier number your engine left the factory with.

Should I replace anything else while the pump is off?

The same Kubota diagram carries the SCV (suction control valve) kit 1J500-50550, the fuel temperature sensor kit 1J500-59630, and the supply pump gasket 1J574-52130. Many low rail pressure complaints actually trace to the SCV or to fuel contamination rather than the pump itself, so it pays to diagnose first. Our common rail system repair department can help you confirm the pump is truly at fault before you spend the money.

Why Buy From Valley Fuel Injection?

Valley Fuel Injection & Turbo has specialized in diesel fuel injection since 1993 and is an authorized Kubota dealer for Kubota engine sales, parts, and service. Common rail is what we do all day: we test, diagnose, and rebuild pumps and injectors in house through our diesel fuel injection services shop. Buy the pump outright, or send us your components through our mail-in rebuild service if you want the whole fuel system gone through by people who live in these systems. Either way you get a genuine part, straight diagnostic advice, and a shop that answers the phone.

Pricing & Availability

Call 530-668-0818 for current pricing and availability on the genuine Kubota 1J770-50504 supply pump, or contact us online. Please have your engine model and engine serial number ready so we can verify the exact current part number for your machine before we quote.