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Size of leak with a failing water pump....


Admittedly my 06 C10 hasnt been ridden much in the last year or two since the FJR and the C14 were added to the collection. I took it to michigan last weekend for a camping trip, and everything was fine. I backed it out yesterday to wash and oil just started dumping from the lower cowling. I pulled the cowling and I'm pretty certain it's the water pump. However, when my 86 water pump started leaking, it was like a couple drops every few days. This was a pretty sizable pool inside the cowling and on the floor so much that I have a drip pan under it for now. Is this possible, can the water pump leak this much?
I've rebuilt a lot of the Connie water pumps, One thing I have seen in older ones ( "new" C10s are now 18 years old) The oil seal "drys out" and actually loosens from its press fit. I use Ultra black on the OD of the seal surface when I rebuild them as over the years even new oil pumps had issues on this seal area ..we stock a rebuild kit as well as offer a rebuild service..

Hey Murph, yeah I was checking out your place yesterday for what my options were. Last I had checked a new pump was available, but was over 200 bucks......so I was surprised/concerned/glad? to see the rebuild service come in a bit cheaper. I just dont particularly want to leave it in pieces for like two weeks. I'm also curious to see if the spillage out of the weep hole is even possible to be as large as I'm experiencing.
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The 06 has history of the oil seal coming out of the water pump. It can be as simple as cleaning the seal and reseating it with locktite or ultra black. Water leak and you want a full rebuild.
reseating it with locktite
Locktite is a brand name normally associated with a "thread locker" , an anerobic adhesive. Anerobic adhesives must have two things to work, metal ions and lack of oxygen. I've been to the Henkel (the locktite people) training class . They never mentioned using a "thread locker" on rubber. As a side note though, there are some of their products that work better when there is a present of oil. I use Permatex Ultra Black as its the best adhesive/retainer I have found for an oil rich environment . Its what we supply in a couple of our kits.

to see the rebuild service come in a bit cheaper
We also offer the same warranty as a new pump. I'll check on availability of new as well, last word I had from my source was they wouldn't be available, moma K may have had a change of heart
I just checked again......not available through my sources...
I can get it locally for about 320 bucks. Yeeesh! What I am also thinking of doing is getting the new unit, installing that, then shipping off my original for rebuild so I can have it in the future. My 06 is 18 years old now, I've had it 10 years, will I have it another 20???
I’ve got a core, if you are willing to put up a hefty🥺. Deposit I’ll refund it once we get your unit and verify it’s rebuildable
I experienced a bit of an oil tsunami on my 86 C10 way back when. The circumstances were that I was on a miles long gentle uphill and was running in 6th gear at ~55 MPH (yeah....probably lugging it). I parked the bike to check-in at that nights hotel and when I returned to the bike, found a puddle of oil on the pavement. It came from the airbox drain.

I'm sure the OPs 06 C10 motor is in better shape than mine was but he did say that he took it to MI on a camping trip. Loaded heavy? He didn't mention headwinds. Anyway, the waterpump is certainly a good place to start in solving this oil leak but it might be worth the time to open up the airbox and see how things are inside it. While there, verify the little elbow hose is properly connected to the airbox and crankcase breather port.
When I bought my 2002 last fall, it had a lot of oil residue in the belly pan and lower left side of the engine case. The seller said he thought it was the clutch rod seal behind the slave cylinder, but after that looked dry, I poked around more, and eventually discovered that the main oil galley plug on the left side below the timing cover was cracked. I couldn't see it until I took the plug out and carefully looked at it, but the flange with the groove that holds the sealing O-ring was cracked, allowing oil to leak past the O-ring. I don't know if someone over-tightened it, or it was a random failure from a weak cast plug, but after a new plug and O-ring, it's been nice and dry.

Airbox leakage from blow-by oil is another good place to check. I thought one of my older bikes was leaking from the shifter shaft, but after cleaning things up and looking closer, it turned to be from the airbox, and the shifter shaft was just the lowest point that the drips ended up coming off.