Sunday, December 9, 2018

Water Pump -- Again!

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Well, I got done with the stator installation, the battery replacement, and the front tire install.  I went for a ride long enough to prove out the stator/battery work and to scuff in the front tire -- a couple of hundred miles or so.

I felt very good about the repairs, and parked the bike in the garage for the night.

Next morning, I found this:


I pointed menacingly to the oil spot on the floor as if scolding a pet that had messed on the floor.

Surely my [pet] motorcycle would not have done such a thing in my otherwise spotless garage. 

I peeked at the engine through the openings in the cowling and found the front of the engine and the inside of the cowlings defiled by an oily, dirty mess spread over a considerable area.

"What have I done wrong with the stator installation?" I asked myself.   It turned out that I didn't do anything wrong over there.  The stator cover is a considerable distance from the oil I was looking at here.  The wind pressure during my 200-mile ride would have caused the left side of the engine, and well behind this, to be oily.

Well, if not that, what? 

I removed the bottom fairings, and wiped down the engine so I could see where the oil was coming from.  I ran the motor until hot, and I couldn't see anything.  (Naturally, it never acts up when you need it to.)

I looked at the oil filter, since I'd just installed it, but didn't see anything leaking there either. 

Finally, I saw some oil coming out of the water pump weep hole.  Just a little, mind you, but oil nonetheless. 


The general neighborhood of the leak.
Closer up view of the vent with the oil wiped away.
The water pump oil seal was apparently leaking.  On this machine, there is a shaft driven by the innards of the engine, that extends out through an oil seal, then a coolant seal to drive the coolant pump impeller.  Between the two seals is a weep hole to the outside. 

That weep hole, by the way, can show both oil and coolant leakage.  The oil side of the water pump drive has an elastomeric shaft seal and the coolant side has a ceramic face seal.  If either of them leak, the leakage comes out of the weep hole.  This design also prevents coolant and oil from mixing should there be a leak between them. 

I had had this trouble before, at 41,000 miles.  Back then it was coolant, so I replaced the coolant seal, buttoned it up again, and it was fine for a short time.  Then the oil seal began to leak and I had to do the repair all over again. 

Now, at 66,000, it has begun leaking oil again, so this time I will replace all the seals at the same time, so I don't have to repeat the task.  . 

I got on the Internet and began looking for the best deal on parts.  I ended up at Ron Ayers Motorsports.

My needs were a bit more pedestrian than stocking stuffers.
I bought the following for my 2006 Ninja 650R:
  • 49063-1055 ceramic face seal $11.65
  • 59256-0007 water pump impeller (in case the old plastic one was stuck and I broke it getting it apart) $20.92
  • 92049-1259 oil seal $4.27
  • 92055-0082 case O-ring $1.74
  • 92055-0083 pump housing seal $4.32
  • 92055-1155 pump cover seal $7.38
The total was $61.68 including a whopping $11.40 shipping charge. 

I punched the order button, and the parts were in my hands two days later.  I began the repair.

I removed the right Inner Cowling for access to the coolant expansion reservoir and radiator cap.  I drained the coolant and removed the five screws holding the pump cover (be careful not to lose the two dowels in the cover).  Then I took the impeller screw out (Put the bike in gear and hold the rear brake to be sure you can apply sufficient torque to the screw.) and the impeller came off the shaft easily.  So, I didn't need to buy that expensive new impeller, it turned out.   Next, I pulled the housing (one more dowel there).  The housing is a very thin aluminum die casting, so be careful not to bend it when removing and handling it.

This is what's left after all that is removed. 


I checked the pump drive shaft for radial clearance that might have caused the seal to fail, but could not detect any. 

I cleaned everything with a rag, then with brake cleaner -- outside to avoid the fumes.

The oil seal can be easily removed from the housing by prying it out with a screw driver.

The cup side of the ceramic face seal for coolant is a different matter.  It is pressed into the housing and there is a sealant on the outside of the seal cup that not only prevents leakage there, but tends to lock the cup in tightly.  I set up a makeshift press using two sockets and my bench vice.


The socket on the left side is bearing on the housing.  The inside diameter of that socket is just slightly larger than the outside diameter of the seal cup flange.  Make sure it is properly centered on the seal before applying force with the vice. 

The outside diameter of the socket on the right is just slightly smaller than the inside diameter of the housing bore that holds the seal cup.

Check all of your metric and English sockets to find the best fits.  If you bend the housing, you will have to replace it to the tune of about $35. 


The coolant seal cup came loose with only moderate force.  I further cleaned the housing with brake cleaner.

I pressed the coolant seal cup flange into the housing using a flat piece of hardwood and a socket on the opposite side to support the housing.

the oil seal is similarly pressed into place with a piece of hardwood.  Its face is to be flush with the highest part of the housing on that side.  It is not to be even with the four recesses. 

The mating half of the coolant seal is contained in the back of the impeller.  It is easily removed with a screw driver.  I opened the envelope containing the new impeller and was surprised to find that it is a nicely-machined aluminum die casting.  The original was plastic.  That is why I was afraid of damaging it during removal. 


I went ahead and installed the new one.  I'll keep the old one as a spare (though I don't expect to wear out or break the new impeller).  The coolant seal is an easy finger press fit into the back of the impeller.

I carefully applied a bit of grease to the various O-ring seals and to the oil seal lip.  The grease lubricates the seal, but it serves to prevent the O-rings from falling out of position when reassembling the pump.  Do not apply grease to the coolant seal faces. 

Clean both faces of the coolant seal with a high flash point solvent.  I used a little brake cleaner on a clean rag.  I carefully wiped both faces, then applied a drop of coolant to both faces to provide the initial lubrication. 

I threaded the oil seal in the pump housing onto the shaft, and pushed the housing against the mating face on the engine.  The one dowel aligns this.  The impeller slips onto the shaft, and the screw securing it is tightened to 87 in-lb.  Again put the bike in gear and hold the rear brake to be sure you can apply sufficient torque to the screw.

The cover went on next (with the two dowels) and the screws were tightened in a star pattern to 87 in-lb.


I reconnected the coolant hose, filled it up with coolant and ran the engine, topped off the radiator when partially warmed up, installed the radiator pressure cap, filled the overflow reservoir to the F mark (with the bike standing upright), and continued running the engine until the cooling fan came on.  Once cool, I rechecked the coolant level in the overflow and set it between the F and L marks with the bike upright. I reinstalled the cowlings so everything looks nice again.  For the time being, I left off the Inner Cowling so I could top off the coolant expansion tank if necessary. 

I was ready for a test ride.




But....

It turned cold, and I didn't have time to go out for a couple of weeks.




Then this:



Phooie!

So I decided to use the time to put on my hand muffs for the winter riding season.  They really help keep the hands warm in concert with the heated grips.



This winter I selected the Ducks Unlimited pair instead of the Hippo Hands brand.  They look better on this type of bike, though they don't protect as well as the larger Hippo Hands. 

When the snow goes away, I'll go out and test the water pump -- and enjoy warm hands!

Maybe I'll see you out there.
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