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What’s up guys, so my bikes been in the shop for a couple months... apparently I need a water pump assembly for my Cx500c, and they can’t find one. If anyone can help, has one, or can point me in the right direction... It would be much appreciated. Haven’t been able to ride in a few months and I’d love to get back out there! Thanks!
 

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There is no "water pump assembly". Part of the water pump is in the rear engine cover. The water pump impeller is attached to the end of the camshaft and there is a water pump cover. See Honda Motorcycle 1982 OEM Parts Diagram for Water Pump / C.D.I. Pulser | Partzilla.com for an image of the components.
Check with your shop and find out what they mean by water pump assembly.
Ok will do. Thank you for that! I’ll try to get them to give me more specifics.
 

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If they insist that there is such a thing as a "water pump assembly" I'd find another shop. Or better yet get some tools and learn how to do this stuff yourself. Paying shop rate for everything that needs to be done to keep any antique vehicle running can quickly empty your bank account....
 

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Ok will do. Thank you for that! I’ll try to get them to give me more specifics.
they probably just meant impeller just used the wrong terminology.....bad news is they are hard to come by new tho used is available..so a 2 months search might not be unusual....they'll at least need to replace a few other parts as well (crush special washers,gasket/seal etc).
Even if not doing the mechanical work yourself pays to look at the FSM(factory manual) to see if the shop quote is reasonable....i.e. realizing that some work will involve dropping the engine and increased costs
 

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It could mean that they noticed the water pump leaking from the weep hole and said the water pump assembly needs to be replaced.
 

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if you look for a replacement impellor - be aware that the 500 and 650 impellors dont interchange as they are differing heights and the 650 one will contact the cover on a 500 motor - likewise the 500 one wont push as much water in a 650 due to excess clearance
 
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The water pump on these bikes consists of an impeller mounted on the rear end of the camshaft that runs inside a cavity that is partly cast into the engine's rear cover and partly the water pump cover that is bolted to the rear cover. There are 2 seals, the water pump cover seal (a shaped o-ring that sits in a groove in the water pump cover to seal it to the engine rear cover) and the mechanical seal which is a sliding seal, one half of which is attached to an aluminum cup that is inserted into the engine rear cover and the other half sits in the back of the impeller.
The weep hole is an opening in the space between the mechanical seal and the camshaft's oil seal that allows any fluid that gets past either seal to escape without working its way past the other seal.

They changed the size of the mechanical seal's cup (& the bore it goes into) at some time during production and the early smaller one has not been available for a long time but if yours is an '82 this should not be a problem.

The Factory Shop Manual says that you have to remove the engine from the frame and remove the rear cover to replace the mechanical seal but forum member Shep figured out how to replace it with the engine in the frame by leaving the cup in the rear cover while pulling the old seal out of it and gluing the insides of a new one in (this has been done successfully hundreds - possibly thousands - of times worldwide).

If you have to pay someone to fix it I would recommend getting in touch with Murrayf on this forum. He's in Lexington, which is a few hours from you but he may know someone reliable in your area.
 

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There are 2 seals, the water pump cover seal (a shaped o-ring that sits in a groove in the water pump cover to seal it to the engine rear cover) and the mechanical seal which is a sliding seal, one half of which is attached to an aluminum cup that is inserted into the engine rear cover and the other half sits in the back of the impeller.
The third seal, an O-ring, is on the water transfer pipe where it seats into the water pump cover.
A leak may develop at any of these seals although a leak at the mechanical seal is the most likely. It is not uncommon for the mechanical seal to leak if the bike has been out of use for sometime. In some cases that leak may go away with use of the engine.
 

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I think you meant that the transfer pipe seats into the water pump cover....
And yes, that o-ring can also fail but I wouldn't expect anyone to confuse it with a "water pump assembly", although a leak from the o-ring can sometimes appear to be coming from the weep hole.
 

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Thanks Bob. Correction made. I need to spend more time with my bikes...but they are so reliable I haven't had to work on them for some time!
 
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