BerkeleyJet Drive Techincal Information:

Overhaul Service Manual
Jetovator Installation
Inducer Pre-Impeller Installation
12JC & 12JG Installation
12J Operation & Maintenance
Trim-A-Just
Berkeley Rudder Installation
12 JE Mold Insert Installation THIS PART IS NO LONGER AVAILABLE
151-25136 Place Diverter Droop Snoot
151-251XX Place Diverter Installation
150-SF2000 Bowl Stuffer
Berkeley Rebuild Guide
455 Berkeley Packajet Engine Manual
Hardin Marine Engine Manual
Transom Cutout
Intake Cutout Measurements
Intake Installation
Impeller Guide
Rebuild Videos

Basic Questions:

Q: What kind of oil do I use in the bowl of my Berkeley Jet Drive?
A: Straight 90 Weight Gear Oil

Use 90 wt.gear oil check every 2 month or 100 hours of operation. To refill the bowl oil remove both of the 1/8" npt plugs on the bowl and using a squeeze bottle of oil force oil into one of the hole still it comes out the other,re-install both of the plugs. You may notice after a while that the bowl bearing area is full of water and not oil. This is a satisfactory condition, (it is best to keep full of oil) as water will leak past the seal, except that this water could cause structural damage to the bowl if permitted to freeze. For winterizing always re-fill with oil before lay-up of the boat.Both oil and or water will both lube and cool the tail shaft bushing at higher rpm levels. The bowl seal is more designed to keep the water out than the oil in as it is installed towards the pressure of the water. The seal will keep the oil or water mixture in the bowl area when the boat hauled out of the water as well.

Q: What are the torque specifications for the Berkeley pumps?
A: Torque specs:

1/2" bowl bolts 70-75 ft.lbs.
5/16" nozzle housing bolts 20-25ft.lbs.
5/16" bearing cap bolts 20-25ft.lbs.
5/16" suction to intake bolts20-25 ft.lbs.
1 1/4" impeller nut 70-75 ft.lbs.

Q: How do I adjust the packing gland?
A: Packing gland adjustment:

The packing gland can be tightened so no water leaks past it, but if it is set up too tight it will overheat and the packing materials useful life will be shortened. If the gland is permitted to leak too much at low speeds the pump could suck air back into the suction piece causing poor acceleration and low speed thrust. So you can see that the gland adjustment is important to the operation of the jet drive. The correct adjustments should be about 1 drop of water per minute at idle leaking past the packing gland. Both of the adjustment nuts should be tightened or loosened equally asto avoid breaking the aluminum packing follower.

Q: How do I maintain the thrust bearing?
A: Thrust bearing maintenance:

Grease thrust bearing every 2 months or 100 hours of operation. (high performance applications should be greased more often)

Q: Can I run my pump while the boat is on the trailer?
A: Running the Berkeley out of the water:

A Berkeley pump can be run out of the water as it has a greased thrust bearing and lubricated tailshaft bushings. The impeller does not touch the wear ring, but due to the fact that the bottom of the pump is open during trailering the boat, it is best to run water into the pump through the nozzle while running on the trailer. The only issues with running out of the water is that after about 15 to 20 minutes the bowl seal can get hot from lack of cooling and cause seal damage. The packing gland may have to be re-tightened when the boat is used the next time as well.