Johnson F5B-9 raw water pump - rebuild question - O ring / gasket missing?-gctid394284

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I haven't changed out my impeller in a long time (probably 10 years), so I figured I do a rebuild to my Johnson pump F5B-9 (Volvo AQ260 - Chevy 350 engine). I've got the rebuild kit which includes a new impeller, seal, cover plate gasket, brass washer and 2 spare cover plate screws. I've found that after removing the cover plate, impeller, seal & brass washer (in that order), I found a small disintegrated rubber washer around the main shaft at the very bottom of the 'stack'. It measures about 20.5mm outside diameter. I found a Johnson instruction manual (rebuild kit didn't have any) on line for a F6B-9 and it says there is an O ring if you remove the bearings (they show the size as: . I'm not planning on removing the bearings. Seems nothing is frozen - rotates fine. There also appears to be 4 'steps' that hold the brass washer away from sitting flush with the bottom. This washer (or O-ring - whatever it is) would occupy that space.

So my question: is this washer/O-ring vital (my water pump was working ok with no leaks). and if so, why wouldn't the rebuild kit have one? If I should be concerned about putting something there, what is the size and/or part number?

I'm also curious if I should put any lubricant down where the bearing live. Thanks much!

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1001skies wrote:

• 1 wrote:
• I haven't changed out my impeller in a long time (probably 10 years), so I figured I do a rebuild to my Johnson pump F5B-9 (Volvo AQ260 - Chevy 350 engine). I've got the rebuild kit which includes a new impeller, seal, cover plate gasket, brass washer and 2 spare cover plate screws. I've found that after removing the cover plate, impeller, seal & brass washer (in that order),
• I found a small disintegrated rubber washer around the main shaft at the very bottom of the 'stack'. It measures about 20.5mm outside diameter.
• I found a Johnson instruction manual (rebuild kit didn't have any) on line for a F6B-9 and it says there is an O ring if you remove the bearings (they show the size as: .
• I'm not planning on removing the bearings. Seems nothing is frozen - rotates fine.
• So my question: is this washer/O-ring vital (my water pump was working ok with no leaks). and if so, why wouldn't the rebuild kit have one? If I should be concerned about putting something there, what is the size and/or part number?
• I'm also curious if I should put any lubricant down where the bearing live.

• 1 wrote:
• You are very lucky to have gotten that many years from an impeller.
  
  If access is good, try pulling the impeller out during winter lay up. It will survive longer when not left in the pump housing during the winter.
• Could this be the shaft seal?
• This may be a Jabsco pump in 1980. How many cover screws are there?
  
  4 screws = Johnson.
  
  6 screws = Jabsco.
  
  Neither pump uses the O-ring at the cover. The kit must cover several different pump models.
• I would certainly replace the bearings and shaft seal.
• Post photos of this pump including the impeller thrust surface deep within the pump body, and the cam.
  
  If either of these a worn, pump action will be compromized.
• With either pump, these will be sealed bearings. In order to do any good, you'd need to pick the seals out, push grease into the ball cage, and re-install the seals. If going to that much trouble, you may as well install the new bearing(s).

FYI: a complete brand new Johnson F5B-9 http://"http://www.amazon.com/Johnso... for $149.</b>

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Thanks Rick. I decided to order a new pump rather than order more parts and deal with a full rebuild. Ill save the kit I bought for the next maintenance (less than 10 years this time!). What prompted the rebuild was a squeaking when at idle which I couldn't be sure where it was coming from. Now you have me thinking the bearings may be worn. Also replacing alternator belt just in case.