Reel Bearings 301: Maintenance, Design, and Troubleshooting (continued)
 

Ball Bearing Troubleshooting: Most ball bearings used in today’s higher-end reels are precision grade radial bearings (ABEC1 and higher), made from stainless steel components.  The bearings may incorporate corrosion resistant configurations and materials (if they are endorsed for use in saltwater).  However, some lower end reels may still use chrome steel, chrome plated or other material for bearings -- which may or may not meet precision standards.  The old adage “You get what you pay for” often holds true when it comes to the internal components in today’s reel, and bearings are no exception.

Corrosion, cleanliness, lubricant, mounting, alignment, design, and the materials used in a ball bearing can affect their performance in a reel as described in the two previous articles in this series.  So with use, ball bearings can wear, become damaged, need lubrication, get dirty, etc. and the bearings should be the first thing to suspect when a reel doesn’t cast or crank the way it once did.  Other components in a reel may slide, mesh, rotate, etc., but ball bearings (or bushings) carry the loads and generally affect the “feel” of a reel more than anything else over time.

Bearing Loads (left) and Loose Bearing Fit (right)

A typical reel ball bearing is usually not designed to carry much axial load, but rather carries mostly radial load on its center race.  In relative terms, the largest radial loads seen in a reel usually occur where pinion and drive gears are supported and aligned, followed by spool bearings (especially on larger bait casters).  [If extremely large axial loads need to be carried, some reel manufacturers may even use thrust bearings, axial ball bearings (races are side by side), angular raced bearing, or incorporate other internal configurations.]

Most reel bearings incorporate what is called a loose fit (or very-light interference fit) with the load that they carry.  A loose fit is where the center race is not firmly pressed onto the load, but rather employs light friction to mate with the center race, and allows some small axial movement of the load through the bearing race.  One of the advantages of a loose fit is that it helps reduce the axial load on the bearing to allow it to track better while rotating -- the net effect is the bearing will rotate with less internal friction, will feel smoother, and any vibration will tend to be dampened while it rotates.  That is why the location where the center race contacts the load may also need to be periodically cleaned and lubricated, in order to maintain the best bearing performance.  A typical ball bearing cannot tolerate much axial load before its rotation and the way it feels becomes adversely affected!

Spool bearing problems seem to occur more frequently than any other bearing problem reported on the various reel forums.  The reason for this is probably due to their high rotational speed, moderate and variable radial loads they carry, and lighter lubrication (when compared to other bearings in the reel).  Poor casts, strange noises or vibration during the cast, and a different feel while retrieving generally indicate a spool bearing problem (more on this later).  Drilled spools and the gap between the side of a spool and the frame can allow water, debris and foreign material to enter the bearings since oil is typically used for lubrication instead of grease.  Spool bearings can also be affected by alignment, and if you’ve ever dropped a reel from waist height onto a hard surface, chances are you’ve had first hand experience in this.  A bent spool shaft due to dropping the reel can result in major bearing alignment problems.

Damaged Bearing Races Due to High Axial Load (Left) and Shock Axial Loads (Right)

Pinion gears can be especially troublesome, because they usually slide axially through the center races of ball bearings, as the reel disengages and reengages with the spool.  If their loose fit is affected by a burr, corrosion or debris, the motion of the pinion can cause the bearing to periodically see extremely high axial loads which can lead to premature wear, distorted races, and deformed sockets that the bearings are mounted in.  Stainless steel pinion bearings that have corroded into their sockets are frequently caused by the repetitive movement of a pinion bearing in its socket due to fretting.  In early stages, the reel may feel a little harder to crank than it used to be, and may also be accompanied by a slight increase in audible noise.  But as the condition worsens it will often begin to feel like meshing gears, until eventually the pinion sticks during travel and the reel will no longer engage or disengage with the spool.  The bearing race shown on the right in the previous picture shows the type of damage sustained due to a reel repeatedly reengaging during the cast (as a result of a worn clutch cam).  The race damage of the bearing on the left is typical of a pinion bearing that carried high axial loads from a pinion gear that didn’t travel as far as it should though its center race.

Ball bearings mounted directly under drag friction washers can also be troublesome, because they are usually mounted toward the outside of the reel where they are susceptible to fouling (e.g. corrosion, sand and debris).  This bearing is also susceptible to the grease being washed out if you regularly rinse your reel after using it in saltwater.  In addition, the drive shaft that travels through their center race is often threaded and prone to burring.  If the loose fit between the drive shaft and its center races is affected by debris or a burr, the axial movement of the drive shaft under varying drag settings can cause the handle to feel rough and noisy when cranking due to high axial load and even a slight bearing misalignment.  If left uncorrected, the ball bearing itself can prematurely wear or become damaged, which can affect the performance of the clutch bearing (causing the clutch to slip, have excess back play, or get noisy), if so equipped.  If this particular bearing gets fouled with debris, needs lube, or gets corroded, it can cause the reel to feel rougher when cranking (and can even feel/sound like you are turning a coffee grinder), especially at higher drag settings.

Spin - First Step in Checking a Radial Ball Bearing Cleanliness and Condition