High strength Torlon bearings require no lubrication. Large diameter bearing race distributes the load over more bearings for low friction while under load. Hardcoat anodized aluminum.
Used on the following boats with standard or furling masts:
• Catalina 380
• Catalina 387
• Catalina 390
• Catalina 400
• Late Catalina 42 with Sparcraft spar
Unfortunately, this size sheave is sold in much smaller quantities than the more common 7/8" ID sheave pictured below. This very limited production causes the part to be more expensive than its very similar cousin.
Replacement Ball Bearing Sheave Dimensions:
• Outside diameter: 3-1/4"
• Inside diameter: 1/2"
• Width: 9/16"
• Line diameter: 1/2"
Original Acetyl Sheave Dimensions:
• Outside diameter: 85mm
• Inside diameter: 12mm
• Width: 15mm
• Line diameter: 12mm
1) Caution! We have occasionally discovered boats built with a spar other than what is expected. If Catalina's current spar vendor couldn't provide a complete spar when needed, Catalina may have been forced to use a spar or components from a different vendor. The only sure way to know if the above sheaves will fit your masthead truck is to measure in advance. If that is not practical, you can always order them in advance. If they are not the correct sheaves you always have 30 days to return them without a restocking fee.
2) This sheave above has been known to be used on Catalina 42's equipped with a furling mast provided by Charleston Spars. The Catalina 400 also used a 12mm (~1/2") diameter masthead clevis pin. These dimensions can easily be mistaken for the 22mm (~7/8") ID ball bearing sheave, part number Z1971 suggested below.
3) When used on a Charleston spar, the sheave pictured above with the 1/2" ID is intended to be used without the plastic bushing used in the original installation.
4) These sheaves are not intended for use with wire halyards.