Are we speaking about Ball bearings? Needles? Rollers?
Either a ball made of Ertalyte® (series 1).
This knuckle can be fitted with stainless steel needles when required (series 15, series 2 and 3) or 1, 2 or 3 rows of barrel shaped rollers (our bearings type 4 to series 7).
Our design department will calculate and advise which model will suit the best your boat configuration.
Will the knuckle swell ?
Knuckles are made of Ertalyte® and do not swell.
My rudder is stiff !
1/ possibly caused by lime scale or mud deposit.
This may happen when your boat has been hauled out for a long time.
Simply pour some hot vinegar solution (from the top bearing if full rudder tube or from top of ½ rudder tube ).
Then, take the knuckle out , check it and clean it.
Would the knuckle look 'worn', replace it,
When the boat is hauled for underwater maintenance such as antifouling works, the rudder bearings should be inspected externally for movement.
2/ the bearing is corroded ; knuckle cannot turn because of aluminium oxyde deposits.
For boats docking at port for extented periods and despite hard anodisation, underwater bearings may suffer from electrical corrosion (source of the electric leakage can be various : your boat, a steel pillar , an electrical cable or your neighbourgh 's boat).
A CORRODED BEARING HAS TO BE REPLACED,
As a prevention against electrolysis, install a sacrificial anode to the bearing (at least to the rudder shaft) and check it regularly.
A corroded anode performs in its job!
How can I take the ball out of the cage?
See sketch above.
I can feel some 'blacklash' from my bearing..
Balls may be worn out.
Lower bearing is highly loaded so lower ball will be worn out before the upper one.
Check both balls and the aluminium parts.
Shall I grease my JP3 rudder bearing?
Type 1 rudder bearings DO NOT require any grease .
Using grease would keep dust, sand or deposits on the ball and may damage your bearing.
Type 1 bearings fitted with O Ring ( # ending with the 3 letters BOR) : using fine oil will help you to insert the ball to its casing.
Type 1 fitted with needles( # 15.XX.XX) need to be lubricated with some water repellant grease .
DO NOT SAND YOUR BEARING
DO NOT PUT ANY COPPER ANTI-FOULING ON YOUR RUDDER BEARING
Installation instructions and maintenance guide are available here.
How can I order spare parts?
Simply follow this link.
Any more questions?
Please contact us.