Overview
Oil seal for the HydraMaster Hydra Pump II. HydraMaster part number 000-147-009, listed as Seal, oil seal for HydraPump 2.
Three are required per pump.
What it fits
HydraMaster's suggested spares schedule lists it against:
- HydraMaster Boxxer 421
- HydraMaster SpitFire 3.2
Any machine running a Hydra Pump II uses this seal. If you know your pump is a Hydra Pump II, this is the seal — check the pump, not the machine.
Where it sits in a pump rebuild
The oil seals separate the crankcase from the water end. When they fail you get oil where water should be, water where oil should be, or both — and a pump that is milking its oil is on a clock.
HydraMaster list three service kits for the Hydra Pump II, and they cover different things:
- 147-009 — oil seals (this part), 3 per pump
- 078-158 — Hydra Pump II high-temperature seal kit
- 078-159 — Hydra Pump II valve kit (also covers the Hydra Pump 5)
A full pump service normally wants more than one of these. Ask us before you order a single item.
Fitting advice
Replace all three together. They have done the same hours in the same conditions.
Inspect the plungers or shafts the seals run on while you have the pump apart. A scored plunger will destroy new seals quickly, and fitting new seals to a scored surface is money spent twice.
Fit seals the right way round — the lip faces the pressure it is sealing against. It is an easy thing to get wrong on a bench at the end of a long day and an expensive one to discover afterwards.
Change the crankcase oil when you rebuild. Milky oil means water has been through the crankcase, and the old oil is carrying whatever wore the seals out.
Frequently asked questions
How many do I need?
Three per pump.
Is this the same as the hot seal kit?
No. 078-158 is the high-temperature seal kit for the water end. These are the crankcase oil seals. Different parts, different job.
My pump oil has gone milky. Is this the fix?
It is usually part of it. Milky oil means water is getting past the seals — but check the plungers for scoring at the same time, or you will be doing it again.
Does it suit the Hydra Pump 5?
Not confirmed in the documentation we hold. The valve kit 078-159 covers both the Hydra Pump 2 and 5, but the oil seal is listed for the Hydra Pump 2. Ask us with your pump details.
Rebuilding a Hydra Pump II? Tell us what you have found and we will put the right combination of seals, valve kit and oil seals together so the pump only comes apart once.
