Kubota BX1880, BX2380, BX2680 Valve Clearance Adjustment
Tags : bx-maintenance | kubota-bx1880 | kubota-bx2380 | kubota-bx2680 | valve-adjustment |BX1880 / BX2380 / BX2680 Owner Service Guide
Kubota calls for the engine valve clearance to be checked and adjusted every 800 hours. Valve clearance is the gap between the rocker arm and the top of each valve stem. The gap changes as the valve train wears, and excessive clearance is one of the causes of hard starting listed in the Kubota troubleshooting chart. Kubota lists this as a dealer service.
| Interval | Every 800 hours |
|---|---|
| Time | 1 to 1.5 hours |
| Tools | Feeler gauge, wrenches, screwdriver, torque wrench |
| Parts | Head cover gasket |
Warning. Stop the engine and remove the key before starting. Check and adjust the valve clearance only with the engine cold.
Specification
| Model | Engine | Intake and exhaust valve clearance, cold |
|---|---|---|
| BX1880 | D722-E4 | 0.145 to 0.185 mm (0.0057 to 0.0073 in.) |
| BX2380 | D902-E4 | 0.145 to 0.185 mm (0.0057 to 0.0073 in.) |
| BX2680 | D1005-E4 | 0.145 to 0.185 mm (0.0057 to 0.0073 in.) |
| Fastener | Torque |
|---|---|
| Cylinder head cover screw, BX1880 and BX2380 | 7.2 to 8.3 ft-lbs |
| Cylinder head cover screw, BX2680 | 5.2 to 5.9 ft-lbs |
| Glow plug | 5.9 to 10 ft-lbs |
Procedure
All three engines are 3-cylinder. Cylinders are numbered 1, 2 and 3 starting from the gear case side. The clearance is checked in two passes, with the No. 1 piston at compression top dead center and then at the overlap position.
- Disconnect the breather hose and remove the cylinder head cover. Remove the glow plugs.
- Turn the flywheel until the 1TC mark and timing line on the flywheel line up with the alignment mark on the rear end plate, with the No. 1 piston at compression top dead center.
- Check these valves with a feeler gauge: No. 1 intake and exhaust, No. 2 exhaust, No. 3 intake.
- If a clearance is out of specification, loosen the lock nut, set the gap with the adjusting screw, and tighten the lock nut.
- Turn the flywheel one full turn (360°) and line up the 1TC mark again. The No. 1 piston is now at the overlap position.
- Check and adjust the remaining valves: No. 2 intake and No. 3 exhaust.
- Recheck all six valves after the lock nuts are tight.
- Inspect the head cover gasket and replace it if it is damaged. Install the head cover and tighten the cover screws or nuts to the torque above.
- Install the glow plugs and the breather hose. Start the engine and check for oil leaks at the head cover.
| No. 1 piston position | Intake valve | Exhaust valve |
|---|---|---|
| Compression top dead center | No. 1, No. 3 | No. 1, No. 2 |
| Overlap (after one full turn) | No. 2 | No. 3 |
Parts
| Part | Part number | Notes |
|---|---|---|
| Head cover gasket, BX1880 | 1G958-14520 | |
| Head cover gasket, BX2380 | 1G962-14522 | |
| Head cover gasket, BX2680 | 16261-14524 | |
| Head cover nut packing, BX2680 | 15951-96660 | 3 per engine |
Parts catalogs: BX1880, BX2380, BX2680.
Related
To have the service done at Messick's, schedule service.
More Articles
Kubota BX1880, BX2380, BX2680 Engine Start System Check
How to test the engine start safety switches on a Kubota BX1880, BX2380 or BX2680, and how to check and adjust a switch that fails.
Kubota BX1880, BX2380, BX2680 Owner Service Guide
Every service interval for the Kubota BX1880, BX2380 and BX2680, with step-by-step owner guides, fluid capacities, filters and part numbers.
Kubota BX1880, BX2380, BX2680 OPC System Check
How to test the operator presence control (OPC) seat switch and PTO shutdown on a Kubota BX1880, BX2380 or BX2680 every 50 hours.
