Low Engine Rpm; Thrust Bearing Excessively Hot; Dry Run Faults; Bearing Seizes When Dry Running - Hamilton Jet HJ212 Installation And Service Manual

Installation and Service Manual

Low engine RPM

Possible cause
Problem with engine
Incorrect impeller and nozzle insert selection
Refer: Engine Manufacturer's manual
Refer to drawing: HJ21203001 Impellers

Thrust bearing excessively hot

Possible cause
Thrust bearing failure
Water seal failure
Refer to section: Bearing Housing Assembly overhaul on page 9-18.
Refer to section: Bearing Housing and Water Seal Assembly Dismantling on page 9-18.

Dry run faults

Bearing seizes when dry running

Possible Cause
Excessive heat buildup
Grit in bearing
Refer to section: Clearing blockages on page 10-46.

Changing sound from the jet unit

Possible Cause
Impeller hitting the wear ring nut due to worn dry run
bearing
Refer to figure: Dry Run Bearing .

Excessive scouring of the shaft sleeve

Possible cause
Operating in dirty water
Solution
Investigate engine operation
Contact C.W.F.Hamilton Ltd
Solution
Overhaul/replace thrust bearing
Replace water seal
Solution
Run in water to cool
Leave overnight to cool
Flush bearing with clean water
Solution
Replace bearing and or sleeve
Check the wear ring for damage
Solution
Do not use high RPM in water when starting off
Try to avoid sucking sand or silt into the jet unit
7-3
Fault Finding