Water pump snafu

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Jul 7, 2014
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Haven't been on my bike for a bit due to knee maintenance, but I came out last week and there was a few drops of coolant underneath the chin. To me, coolant problems are the worst. After taking all the plastic off, I rented a pressure tester and found that it's leaking underneath the water pump housing, not the weep hole. Hard to imagine the pump going out with less then 23,000 on it. Any thoughts?
 
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If it is coming out along the front seam, and out of the square drain hole, it's just loose hose clamps on the water pipe fittings.
This is very common. Search forum for coolant leaks.
 

Scooter

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Just for clarity, what do you call the weep hole? The round hole or the square one?

It's not uncommon at all to see a little bit of coolant on the ground after it has sat for a long period of time. I had the same question when I had my first ST1300 (2003 ABS) and it was how I ended up discovering this site. As long as you have the plastic off now you could go in and gently tighten any of the hose clamps that you can access up in the area of the V. You don't need to over tighten them.

Where is the level of coolant in your overflow bottle sitting at? If its fine, I would just button it back up and ride it.
 
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To answer the questions, the fill bottle is 1/4" above the bottom line and at first, the leak was only from the round weep hole. When I used the pressure tester is when it was coming out of the seam and square weep hole. Since it's time to change the coolant, I think I'll take the radiator off and change some clamps. After reading some of the posts concerning the use of the old style clamps, it makes sense since everything is already off. As always, thanks for the help!
 
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Just to update a bit...I took off the radiator today and was expecting a little evidence of coolant around the hoses coming from the thermostat like most of you have spoken of. But the intire area was dry. Not even a hint of coolant. Just the accumulation of road dirt and grime. So now I'm wondering if by using the pressure tester, did I make a small problem into a new water pump? My Honda shop manual says that if the leak is from the round weep hole then replace the water pump. Looks like that's what I'll be doing.
 
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Alright Igofa! Thank you! I see from a post from last year that you have done this already. Can the install be done without all of the special tools the book says to use? I have a vice, C clamps and a few other tools that looks like could get the job done but not a spherical bearing driver.
 
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PM me a contact number and I'll call you tomorrow and discuss this with you. Unable to type enough right now.
 

Blrfl

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So now I'm wondering if by using the pressure tester, did I make a small problem into a new water pump?
No, probably not. The thermostat housing isn't the only place up top that's known to leak. The two fittings at the top of the engine where the coolant exits are also famous for not holding. What they leak runs down through a drain channel that exits at the bottom of the water pump housing. If the fittings were leaking and you put the system under pressure, what they squirted out would have ended up down there, too.

My Honda shop manual says that if the leak is from the round weep hole then replace the water pump.
Make sure it's an actual, continuous leak and not just a few drops that escape while the seals expand. Honda added a fitting and drain hose where the weep hole is to 2008 models because they were doing a lot of water pump replacements under warranty for normal behavior.

--Mark
 
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Just to update a bit...I took off the radiator today and was expecting a little evidence of coolant around the hoses coming from the thermostat like most of you have spoken of. But the intire area was dry. Not even a hint of coolant. Just the accumulation of road dirt and grime. So now I'm wondering if by using the pressure tester, did I make a small problem into a new water pump? My Honda shop manual says that if the leak is from the round weep hole then replace the water pump. Looks like that's what I'll be doing.
I ran into the same thing you did on my 2007. All was dry on top. I found that the water pump housing/cover oring gasket was leaking around the alignment dowel and leaking out the square hole. I replaced the gasket using a small amount of water pump grade silicone sealer and all went well for about a month when I started it up on a 50 degree morning and it started leaking again but only on that
one morning. The slight antifreeze smell is back so.. I duno. Im gona run it until riding season is over. Using the silicone sealer might not have been such a good idea. I mentioned this in another post you may find later on.

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