Water Pump Weep Hole Upgrade

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I've read where in 2007-2008, Honda upgraded the crankcase housing with a drain hose/fitting at the pump weep hole.

Has anyone successfully upgraded an earlier bike to this configuration? If so, what did you use for a fitting or did you replace the whole housing?
 

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SupraSabre

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I actually bought a 2008+ cover with waterpump installed. I was going to mount it on my '04#1, but now it looks like I'll be tearing into my 2010 and replacing the clutch springs (and friction plates) before too long, so I'll probably use it for that.

Then, I'll rebuild the waterpump on the old 2010 cover and use that on the '04#1.

Ask anybody, that's just how I work...this goes on that one and only after I do that to the other one...:rofl1:
 
OP
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M1-Shooter
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Thanks for the response. That makes wonder, is it a direct replacement?

Interesting that you can buy one ready to go, pump installed. What is it missing? Just a new gasket for the case?
 

SupraSabre

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Thanks for the response. That makes wonder, is it a direct replacement?

Interesting that you can buy one ready to go, pump installed. What is it missing? Just a new gasket for the case?
I picked it up on ebay, I think it was like $200. No gasket included.

You can get them that way from Partzilla : COVER, FR. CRANKCASE 11340-MCS-D80 $250.18
 

Blrfl

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Thanks for the response. That makes wonder, is it a direct replacement?
If the parts it bolts into were the same for 2008 bikes as they were in earlier years, it should bolt right on.

Seems like a lot of cash and labor to expend on something that isn't much of a problem.

--Mark
 
OP
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M1-Shooter
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What about pressing in a brass nippl,e then attaching a hose. Seems a lot easier than pulling the cover. Yes?
That's why Im asking really.

If I can mimic or retro fit my 06' to the current installation, Id like to know if I can buy the detail part and just tap and thread the weep hole.

Dont want to pull the cover, unless I can't upgrade it.
 
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You would have to remove the cover to drill and tap it anyways to make sure you got everything cleaned out.
All you would be doing is directing your coolant leak to the floor under the nose of the bike instead of down the right side of the bike.
.02
 

Dave.David

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My concern is someone who might do this is trying to put off replacing the water pump. Likely not knowing why the hole is important, the warning it's signalled.
When that seal goes, and it is on its way out, that's it, engine cooked.
It's called a idiot light because the light is saying "to late idiot."
I'm not calling anyone a idiot, I'm asking do people know the risk?
 
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A valid concern, and I certainly don't take offense to the "idiot" term. Reminds me of stories I have heard about people taping down breakers so they don't pop in airplanes! :)

In my case, I have have an observed weep from the hole (however slight it is). Never a drop on the ground, ever. Just that lower right corner of the bike is all coated. Now in full disclosure I've been mainly an ST owner and not a rider the last 18 months. Taking the bike out occasionally to keep things turning on the bike and in my head. The seep was there when I was a more prevalent rider and has not gotten worse. I would like to replace the water pump and/or mechanical seal, and if I'm in there...I can upgrade or retro-fit my current cover to the hose style. No leaks from the hose clamps under the throttle body.

You could call my bike the typical example, I've had basically the normal failures the average owners have had. Thermostat, etc. Based on my searching, it seems guys will replace the water pump and a couple thousand miles later, the seep will return. Apparently Honda knew something was going on?
 

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It's normal to have a "minor amount" of seepage out of the weep hole. Seepage is an area of dampness that over time collects road grime on the side of the engine. Trouble is "what is minor" is different to different people added to the fact the square hole drain channel for any weeps, seeps, or leaks from the coolant system is physically very close by. Air whipping around under the fairing creates grimy deposits on the lower right side of the engine from coolant weeps/leaks and these masquerade as water pump leaks. This is why Honda changed the weep hole to an external tube w/hose to clearly separate the two sources. If no one has looked at the area in 25,000-50,000 miles suddenly they might have cause to freak out and change an expensive water pump on Honda's dime or their own when it's really a hose clamp(s) that needs attention.

Discovery of oily grime residues on the lower right side of the engine could be either and likely more one than the other. A good cleaning of the area followed by closely monitoring for some period of time should indicate what is actually seeping/leaking with little danger of a catastrophic event. It just doesn't happen in our collective experience. Is is easy to remove the tipover wing cover and peer inside there and the opening for the oil level glass with a flashlight to monitor the area.
 

Blrfl

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What Dave said.

The other thing to check is if you've got crusty green stuff on the front of the clutch housing or on the inside-facing side of the nose of the fairing. That's almost entirely hose clamps.

We saw a lot of people draw the coolant-means-failed-water-pump conclusion in the early years only to have to go back and do the clamps after a water pump replacement.

--Mark
 
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It's normal to have a "minor amount" of seepage out of the weep hole. Seepage is an area of dampness that over time collects road grime on the side of the engine. Trouble is "what is minor" is different to different people added to the fact the square hole drain channel for any weeps, seeps, or leaks from the coolant system is physically very close by. Air whipping around under the fairing creates grimy deposits on the lower right side of the engine from coolant weeps/leaks and these masquerade as water pump leaks. This is why Honda changed the weep hole to an external tube w/hose to clearly separate the two sources. If no one has looked at the area in 25,000-50,000 miles suddenly they might have cause to freak out and change an expensive water pump on Honda's dime or their own when it's really a hose clamp(s) that needs attention.

Discovery of oily grime residues on the lower right side of the engine could be either and likely more one than the other. A good cleaning of the area followed by closely monitoring for some period of time should indicate what is actually seeping/leaking with little danger of a catastrophic event. It just doesn't happen in our collective experience. Is is easy to remove the tipover wing cover and peer inside there and the opening for the oil level glass with a flashlight to monitor the area.
This is the BEST description and explanation I have read to date!
Most folks will NEVER see any coolant on the floor under their bike because it weeps out slowly and the heat of the engine steams it away, leaving nothing but odor and a green stain on the side and or front of the motor.
When ignored, this will start to gather road grime and appear to be a major oil or coolant leak and confuse folks, probably including Honda, which is why they probably changed their wording in the service manual.
As Dave said, completely clean the engine, then keep an eye on it for the next couple days, and you will more than likely see where it is leaking from, and how bad.
Some of the most common area's are the T-stat o-ring, large radiator hoses, water pipe fittings, radiator cap, and the 3 way Tee fitting off one of the hoses by the cap (these crack and only show signs of leakage when wiggled around).
.02
 
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What Dave said.

The other thing to check is if you've got crusty green stuff on the front of the clutch housing or on the inside-facing side of the nose of the fairing. That's almost entirely hose clamps.

We saw a lot of people draw the coolant-means-failed-water-pump conclusion in the early years only to have to go back and do the clamps after a water pump replacement.

--Mark
:plus1:
 

SupraSabre

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I think Honda added the weep hole hose because too many dealers were getting confused on a leaking waterpump and a hose from above (square hole leaking).

A simple fix to keep from $$$ in warranty work by Mother Honda!
 
OP
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M1-Shooter
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Appreciate the response. That's why I was careful to use the word seep. There is no appreciable loss of coolant, at least as I attempt to monitor the overflow/expansion tank.

The lower right quadrant of the engine (and the bottom cooling fins) are just getting that mist and road grime coating you so accurately described. For my bike (2006 w/ 38k on the ODO), with the cover removed, I can hold the throttle at 3K rpm and watch the weep hole and a small "tear" if you will, with go in and out...like it is hesitating to drop. It feels like that Geico commercial with the old guy that has a dollar on the fishing pole. "Oh, you almost got it."

Multiply that over sever hours of riding, and more days/weeks/months...it can add up to a messy engine. From an objective viewpoint, I can still see a reason to address the mechanical seal. But...maybe I am on the wrong side.

To be clear, I know its coming out of the weep hole.
 
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SupraSabre

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Appreciate the response. That's why I was careful to use the word seep. There is no appreciable loss of coolant, at least as I attempt to monitor the overflow/expansion tank.

The lower right quadrant of the engine (and the bottom cooling fins) are just getting that mist and road grime coating you so accurately described. For my bike (2006 w/ 38k on the ODO), with the cover removed, I can hold the throttle at 3K rpm and watch the weep hole and a small "tear" if you will, with go in and out...like it is hesitating to drop. It feels like that Geico commercial with the old guy that has a dollar on the fishing pole. "Oh, you almost got it."

Multiply that over sever hours of riding, and more days/weeks/months...it can add up to a messy engine. From an objective viewpoint, I can still see a reason to address the mechanical seal. But...maybe I am on the wrong side.

To be clear, I know its coming out of the weep hole.
Until it actually starts dripping to the ground, I would just keep riding. As far as the engine looking a little ugly, you can clean it off.
 
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I think Honda added the weep hole hose because too many dealers were getting confused on a leaking waterpump and a hose from above (square hole leaking).

A simple fix to keep from $$$ in warranty work by Mother Honda!
:plus1:
 
OP
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M1-Shooter
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Until it actually starts dripping to the ground, I would just keep riding. As far as the engine looking a little ugly, you can clean it off.
That's how I feel about it.

I just want my feelings to be normalized. :) Now, if I ever sell the bike (which may happen in the future)...I want it to be correct I guess.
 
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SupraSabre

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That's how I feel about it.

I just want to my feelings to be normalized. :) Now, if I ever sell the bike (which may happen in the future)...I want it to be correct I guess.
Last year at this time, I had just finished getting my 2004 #2 ready to be sold (de-FARKLEd), rode it to the gas station, and I could smell coolant! I took it back home and sure enough, it was leaking out the weep hole! So it, along with my 2004 #1 both need waterpumps! :eek:4:

I did try to sell it, but nobody would buy it!
 
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