94 K75 oil/water pump rebuild journal

[Motorhobo]

Pretty sure it's oil pump/water pump rebuild time using the IBMWR.org instructions at https://ibmwr.org/index.php/2003/05/01/water-oil-pump-rebuild/ and the excellent Youtube video from kennyraceboy at .

The bike is a 94 K75 which I bought with 63K on it and now has about 83K. When I bought it I pulled the oil pump cover off and resealed it since there was some kind of corrosion around the mating edge. Oil started dripping from the weep hole a couple months ago. While it was just a drip I continued to ride it. I stopped riding the bike about two weeks ago. It seems like the leak has gotten progressively worse even though the bike is just sitting and now it's making a regular puddle, at least it would if I didn't put cardboard under it.

I drained the oil and coolant, neither appear to have any cross-contamination.

So the first question is what conclusions I can gather from the fact that the leak 1) gotten worse without riding the bike and 2) there's no coolant in the oil and no oil in the coolant. Is this likely just the seal failing? Which brings us to the second question: what is the likelihood that whatever is wrong can be fixed by swapping out the non-leaking oil pump on my other K75, since I'll be removing and junking that engine anyway soon. If it's just the seal failing, then replacing the oil pump with a non-leaking one from a different bike won't help me because the seal will have to be replaced regardless of which pump I'm using.

So in summary -- is what I have here indicative of a bad seal or a bad pump? If it's the former, I'll replace the seals on the existing pump. If it's the latter, I'll try it with the other pump.

In the meantime, I want to have all the ducks in a row to do this job. kennyraceboy says this specific tool is a big help in installing this seal which is prone to not going in straight. I'd like to make a 3D printed facsimile from PETG, which should be strong enough to do the job. Don't laugh -- I made this wheel bearing locknut socket for my stone-age Ford Explorer out of PETG and it did the job, much to my surprise. Anyway, if anyone has this seal install tool and/or can give me the exact dimensions I can make one and put it in the 3D print section.

[frankenduck]

If you have a spare non-leaking pump I would just swap.  No parts to buy and no seal replacing project required.

If rebuilding then, as pointed out in the IBMWR write-up, be sure to loosen the impeller bolt before you take the pump off.

No special tools required as you can use sockets to drift the seals in.

Here's my notes with links to another WP YouTube:
http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/K1100LT.Water.Pump.V1.2_compressed.pdf

[daveson]

One thing I would try is item number one from my lazy man's tool box, do nothing, especially if you didn't use it much before you stopped riding it.

My brick is parked on a sealed concrete floor and never dripped one drop of coolant (or oil) on the floor. During the first wave of the virus, motorbikes were banned from Victorian roads. I think it was more than a month I didn't ride When I took it back on the road, I noticed coolant on the floor, the leak stopped when I started riding again. I've never messed with a bricks pump, dunno zilch about it, but guessed a seal dried out, then it come good again with use.

[Motorhobo]

I'm afraid 'do nothing' isn't an option -- it was my daily rider before it started leaking and judging by the size of the oil puddle that appears on a daily basis it's not going to fix itself by any means. I don't know how long you can go without having to deal with oil pump issues but I figure with +80k it's on borrowed time anyway.

[frankenduck]

I'm afraid 'do nothing' isn't an option -- it was my daily rider before it started leaking and judging by the size of the oil puddle that appears on a daily basis it's not going to fix itself by any means. I don't know how long you can go without having to deal with oil pump issues but I figure with +80k it's on borrowed time anyway.

Just as a point reference I've had WP issues on two 93 K1100LTs, one at about 50K (I replaced seals) and another at about 75K (swapped in another WP.)

[Motorhobo]

Just as a point reference I've had WP issues on two 93 K1100LTs, one at about 50K (I replaced seals) and another at about 75K (swapped in another WP.)

Thanks. I'm inclined at this point to replace the seals rather than swap in the pump from the engine with 130k on it. I know I had the WP was replaced on that engine at some point, not sure when exactly, probably close to 70k miles ago, so it's no spring chicken either. I'd hate to swap it in just to have it fail. I think I'm going to put off the engine swap for now and ride that bike with the 130k engine and hope it doesn't crap out while I do the seals on the summer bike. I'll probably get around to it in mid-November.

[stokester]

Did you get the new spacer bushing to be used with the new style slip ring seal?

I made that mistake on my first rebuild, just used the old spacer not knowing the new seal required one of a different size and had a much worse leak.  The original spacer is 14mm while the new one is 10mm.

[boxer.randy]

I’m with Daveson on this. If I let my 92 K75S sit for a month it will drip a few drops of gear oil. When I ride it - no drips. I think these bikes get grumpy when ignored.

[Motorhobo]

I’m with Daveson on this. If I let my 92 K75S sit for a month it will drip a few drops of gear oil. When I ride it - no drips. I think these bikes get grumpy when ignored.

Like I said, this is my daily rider. It never sat for more than 2 days before it started dripping. Now it's a gush. Read my response to daveson. Riding a bike that clearly has a bad WP seal isn't very good advice, IMO.

[Motorhobo]

Did you get the new spacer bushing to be used with the new style slip ring seal?

I made that mistake on my first rebuild, just used the old spacer not knowing the new seal required one of a different size and had a much worse leak.  The original spacer is 14mm while the new one is 10mm.

Not sure -- I bought a rebuild kit a few years ago then ended up not needing it because it wasn't a problem with the pump or seals, just the cover needed to be re-sealed with gasket sealant. I will make sure to check all the parts before I do anything.

[Past-my-Prime]

As I'm sure your youtube watching has revealed, the weep hole is to keep the coolant and oil separate, and one or the other will drip out the hole before migrating past two seals. If I recall correctly, anyhow. I managed to use the seal replacement kit (and I bought the tool specific for seating the new one) and uncommonly for me I did it in one go. It had been leaking oil out the weep hole for a year or more, never got to be a gusher but was enough to bother me.

[Motorhobo]

As I'm sure your youtube watching has revealed, the weep hole is to keep the coolant and oil separate, and one or the other will drip out the hole before migrating past two seals. If I recall correctly, anyhow. I managed to use the seal replacement kit (and I bought the tool specific for seating the new one) and uncommonly for me I did it in one go. It had been leaking oil out the weep hole for a year or more, never got to be a gusher but was enough to bother me.

Thanks for the useful info - no, I guess I missed that function of the weep hole in my YouTubing. Not sure how long it's been dripping. Probably longer than I'd like to admit. I spent months in denial, attributing it to other, less ominous things that I was too lazy to fix.

So you have this special bearing-seating tool? Can you give me the dimensions and a pic? I'd like to try and 3D print one.

[frankenduck]

I used a 27mm socket. The IBMWR write-up used a 1 1/16 socket which is 26.99mm.

[Motorhobo]

OK - I guess I'm just wondering why they have a 'special tool' when the un-special ones work just as well.

[stokester]

This is what I have used.  A PVC straight joint with a chamfered end.

[Past-my-Prime]

Thanks for the useful info - no, I guess I missed that function of the weep hole in my YouTubing. Not sure how long it's been dripping. Probably longer than I'd like to admit. I spent months in denial, attributing it to other, less ominous things that I was too lazy to fix.

So you have this special bearing-seating tool? Can you give me the dimensions and a pic? I'd like to try and 3D print one.

It's got an outer and an inner dimension, like two sockets nested within one another, which helps to keep the whole works "square". Skilled mechanics like some of our esteemed colleagues can probably make do with old pieces of pipe and sockets, but I need all the help I can get!

When I'm next home, I'll take a bunch of photos, and then struggle mightily to get them to actually load up (usually, but not always, won't transfer from "my gallery" to the actual post I'm trying to make, if my memory serves correctly, about which I make no guarantees, or my wife either for that matter.

[frankenduck]

our esteemed colleagues

I resent that implication. I'm just a run-of-the-mill shadetree mechanic who is too cheap to buy the proper tools.

[Motorhobo]

I resent that implication. I'm just a run-of-the-mill shadetree mechanic who is too cheap to buy the proper tools.

Right, well, I guess by comparison that makes me a thumb-fingered incompetent who should be paying real mechanics but is too stubborn and poor, but is also too cheap to buy the proper tools. Which is why I try to 3D print no-cost facsimiles whenever possible.

P-M-P, if it's easier, PM me and I'll send you my email addy, and you can just shoot me the pics that way. No point hosting them here anyway and adding the extra unnecessary overhead for pics nobody wants to see but me.