Kubota Diesel Tractor Starter Motor | OEM 15231-63012

Kubota's B-series did more than any other line to put a diesel tractor on small acreage, and the starter that turned those engines over was deliberately modest: a Denso direct-drive unit of 0.8 kW, twelve volts, nine teeth turning clockwise, 4.4 kg complete, with a 28.7 mm drive gear and a 10 mm mounting hole. 15231-63012 covers the B5100 of 1978 and the B1550 that followed it into 1997, the B6200, B7200, B8200 and B1750 of the eighties, the B7100 that stayed in the catalogue for most of a decade, and the G1800 garden tractor built until 2000, all of them running the D750, D850, D950 or Z600 diesel.

OEM and Search References

• Primary Kubota reference: 15231-63012, following 15231-63010 and -63011 and leading on to -63013 and -63014

• Alternative Kubota numbers: 15271-63014, 15852-63010, 19293-63010, 19837-63010

• Denso numbers: 028000-3500 and 028000-7460, the pair most rebuilders quote from first

• Aftermarket and rebuilder codes for the same motor: SND0242, WAI 410-52045, LRS00217, 3974246

• Ratings: 12 V, 0.8 kW, 9 teeth, CW, Denso direct drive, 4.4 kg

• Measured at the gear: 28.7 mm outside diameter, with a 10 mm mounting hole

• Engines: D750, D850, D950 and Z600; B5100 1978-1984, B6200 1983-1992, B7200 and B8200 1983-1990, B1750 1988-1996, B1550 1988-1997, B7100 1990-1997, G1800 1989-2000

Fitment and Purchase Checks

A tractor this old has usually been through two or three starters, and the ones that failed are often still in the shed, which is a gift to anybody who thinks to measure them. The 28.7 mm gear and the 10 mm hole are the two figures that separate this unit from the larger direct-drive motors used on later B-series machines, and neither is printed anywhere on the tractor. Photograph the plate, measure the old gear across its teeth, and the enquiry answers itself; what comes back is a price per carton, the stock behind it and a dispatch date that can be worked into a repair schedule.