CAT 3CP Hot & Dry Seal Kit. A replacement seal kit for Cat Pumps 3CP series triplex plunger pumps, catalogued by HydraMaster as part 078-271.
Fitment
- CAT 3CP series pumps
- HydraMaster lists 078-271 as "Kit, Seal for 3CP Cat Pump" in the parts list for the CDS 4.6 and CDS 4.8 truckmounts, which run a Cat 4.2 GPM triple plunger pump
The 3CP is used on more than one make of truckmount. Check the model plate on your pump before ordering, and tell us the pump model if you are unsure.
Hot and dry duty
This kit is specified for hot and dry running conditions — higher temperature seals for a pump working harder than the standard kit assumes. Carpet cleaning truckmounts run hot solution continuously, which is exactly that duty.
Fitting a standard kit to a machine running hot gives you a shorter service interval and a repeat of the same job. Match the kit to the duty.
Seal Kit and Valve Kit
A 3CP rebuild usually involves two kits. HydraMaster lists the seal kit (078-271, this part) and a separate valve kit (078-270) for the 3CP, and recommends carrying both as spares on the CDS to minimise downtime. CCW does not currently list the 078-270 valve kit online — ask us if you need it.
Fitting Advice
- Isolate the machine and release all water pressure before opening the pump.
- Replace the seals in all three cylinders at the same time, not just the one that is leaking.
- Inspect the plungers while the pump is open. A scored or pitted plunger will cut new seals quickly.
- Follow the Cat Pumps service manual for the 3CP for assembly order and torque values.
- After a rebuild, run the pump with water before returning to hot chemical work and check for leaks at the manifold.
Specifications
| Pump | Cat Pumps 3CP series |
|---|---|
| Duty | Hot and dry running |
| HydraMaster part number | 078-271 |
| SKU | 078-271 |
Frequently Asked Questions
Why do seals fail early on a truckmount pump?
Heat, running dry, and chemical attack are the usual causes. A pump that is starved of water, or run at temperatures beyond what its seals are rated for, will wear seals faster than a pump on cold water.
Does this kit include the valves?
No. Valves are a separate kit (HydraMaster 078-270).
Will it fit a Cat pump that is not a 3CP?
No. Cat seal kits are specific to the pump series. Check the model on the pump plate.
See also Cat Pumps and Pump Repair Kits & Seals.
Tell us the pump model and serial number and we will confirm the kit before you order.
