Cooling System Question

[SMSW]

I noticed a drop of green fluid on the garage floor under my bike today while I was taking the tupperware off for some winter maintenance. On the right side of the bike, if you follow the fat radiator hose to the bike, it terminates on what I think is the water pump intake pipe. Immediately aft of the water pump pipe is a small, 1/4" tube that leaves the engine. This pipe seems to exit from the alternator housing casting (?); the engine block is behind this seam. A black hose is clamped onto this 1/4" tube and leads down under the crankcase and vents to the atmosphere. I looked in the service manual and could not find this hose in the cooling system section.

Is this a breather or drain hose? This is the source of my drip. There is no obvious other leak on the front of the engine (though I have not yet pulled the left tupperware). The bike is a 2010, w/ 24k miles.

 

[Andrew Shadow]

Maybe you are looking at the drain hose that runs from the water pump shaft seal weep hole.
Have a look at the picture in post 13 of this thread- https://www.st-owners.com/forums/showthread.php?142400-What-is-the-function-of-the-two-drain-hoses-under-the-ST-1300/page2

 

[SupraSabre]

Honda was replacing too many waterpump seals, so they added that little pipe there so it would be as noticeable when coolant or oil "seeped" out. Some seepage is normal, but usually you don't see any on the floor. If you get excessive leakage there, it could mean that you have a bad waterpump seal.

If your bike is still under warranty, take it to your dealer and they should fix it without charging you.

One thing to check is to see how low your coolant overflow bottle is (under the left side maintenance cover on the mid fairing). The coolant will just be visible with the cap opened, looking down into it (use a flashlight). If you have to fill it (don't overflow it), measure how much you put it. Ride the bike for a couple of hundred miles and see if the coolant level goes down.

 

[SMSW]

Yes, I'm looking at the water pump shaft seal weep hole. There was only one tiny drip on the floor. I started the bike up about a week ago and moved it into the garage area where I plan to work on it over the winter. Warranty is over, I think, but I will check that with Honda and keep an eye on it.

If Honda was "replacing too many seals" that suggests that the seal is separate from the pump? Or do I get a whole new water pump too? The fiche for the front crankcase cover shows the water pump and a 'mechanical seal'. Does this crankcase cover have to be removed to replace said seal?

 

[SupraSabre]

Yes, I'm looking at the water pump shaft seal weep hole. There was only one tiny drip on the floor. I started the bike up about a week ago and moved it into the garage area where I plan to work on it over the winter. Warranty is over, I think, but I will check that with Honda and keep an eye on it.

If Honda was "replacing too many seals" that suggests that the seal is separate from the pump? Or do I get a whole new water pump too? The fiche for the front crankcase cover shows the water pump and a 'mechanical seal'. Does this crankcase cover have to be removed to replace said seal?

No, the dealers were seeing a little weeping and replaced because of that! My dealer even replaced mine because of that. But then, 50K later when it really was leaking, they insisted nothing was coming out of it...I replaced it myself at that point and haven't had the dealer do anything to my bikes, other than warranty work when I didn't want to do it myself.

 

[SupraSabre]

Oh, they love playing games! When I took the 2010 in last year to have the brake recall taken care of, they also "attempted" to fix my ABS light staying on all the time. After replacing the front sensor, the rest of their fix was for me to purchase a new ABS Computer (@~$1,100) and if that fixed it, they "would see" if Honda would cover it from warranty. Since it was in a major accident (before I bought it), Honda probably would have wiggled out of covering it. Instead, I waited for ebay to produce a good later model ABS Computer, which I picked up last May or June for about $250 or so. One from a wrecked cop bike with only 409 miles on it. I bought several other items from that bike too, like the speedo, complete lock set including the saddlebag hardware, right handlebar controls, etc...)

 

[Igofar]

Typical use of customers bike to generate money while under warranty even though it didn't probably need it the first time they billed honda for sure.
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