A useful upgrade I've made to the Harbor Freight towable backhoe was swapping out the stock hydraulic pump for a larger one.
The difference in performance is notable - with the stock pump (2.7 cc), movements are slow and working with the machine can feel tedious. With the upgraded pump (4.1 cc), everything runs noticeably faster and more smoothly. You can even operate two controls at the same time— something that wasn’t possible with the original pump.
About the upgraded pump
- Model:
1.6PB4.1D-R080S0 - Alternative model:
1.5PE4.1D-R80S0
(The 1.6 was superseded by 1.5. Both have identical mounts and port locations, but there are some cosmetic differences.)
Note: Research suggests these backhoes can handle pumps in the 4.0–4.5 cc range.
Adapters
Because the new pump uses standard threads while the Harbor Freight backhoe is metric, you’ll need two adapters (for the pump inlet and outlet).
Outlet hose adapter: 6MB-6FP Purchase link...
Inlet hose adapter: 8MB-8FP Purchase link...
Removing the Old Pump
- Disconnect hoses. Start with the smaller outlet hose at the top of the pump. Next, remove the larger hose from the bottom (this runs to the hydraulic reservoir).
- Unbolt the pump, held in place by two bolts.
- Remove the coupler. You’ll reuse the coupler from the old pump - It’s secured with a small set screw that you can loosen with a T25 Torx bit.
Installing the New Pump
Once the coupler is transferred, mount the new pump with the same bolts, attach the adapters, and reconnect the hoses. From there, you’re ready to refill your hydraulic fluid and test it out.
Final Thoughts
This upgrade is straightforward, inexpensive, and makes a big difference in usability. For about $175 and a bit of time, the backhoe becomes faster, smoother, and far more capable.