Leak from Round Hole

[Tdinova]

I done a search and could not find my problem exactly.

Well the deeper leak showed up. A few years ago I had the square hole leak which was easy but hard to stop. I removed the rad, throttle body and re-tighten the clamps, bought a new thermostat and o ring and all went well...

Today I removed the plastic and there is clean antifreeze dripped out the round hole while idling. Not all the time but 4-5 drops then stopped. Im here watching it idle for 4-5 mins and no more drops.

My question is, can I just change the antifreeze seal on the water pump or do I have to replace it all?. I know the rad and motor cover has to be removed which is easy...

Or top up the antifreeze and forget about it until late fall..
.

Any help will be helpful.

And Happy Canada Day from up north

 

[SMSW]

Since the weather is gorgeous, riding time in Canada is limited by seasons, and your leak is so small, I would suggest you check the coolant level in the overflow tank weekly and wait until your winter layup. If you do not have a heated space in which to work, then do the work this summer or fall. If the leak gets worse, that will change the equation.

 

[AV8R]

I had a leak like that, but gradually got worse. The problem was the coolant bottle got brittle and developed a crack. Replacing it wasn’t too hard or expensive. Think I posted a thread on it here somewhere.

 

[SupraSabre]

If it is seeping out of the little round hole on the right side of the engine (the waterpump), chances are, the overflow bottle is not the problem.

I have changed out three waterpumps so far and I'll be doing another two very soon. It requires the front cover to be removed, and that's a PIA. I agree with SMSW, wait until riding season is over, just check the overflow bottle before each ride and top it off.

My friend Bill, who bought the '04#2 from me, was warned ahead f time that his was leaking. We'll be doing that bike's as well as my '04s.

Also, depending on how many miles you have on your bike, (above 60,000 miles - not sure what that is in Kilometers...) I would replace all the clutch plates since you have it opened.

Good luck!

 

[fnmag]

I done a search and could not find my problem exactly.

Well the deeper leak showed up. A few years ago I had the square hole leak which was easy but hard to stop. I removed the rad, throttle body and re-tighten the clamps, bought a new thermostat and o ring and all went well...

Today I removed the plastic and there is clean antifreeze dripped out the round hole while idling. Not all the time but 4-5 drops then stopped. Im here watching it idle for 4-5 mins and no more drops.

My question is, can I just change the antifreeze seal on the water pump or do I have to replace it all?. I know the rad and motor cover has to be removed which is easy...

Or top up the antifreeze and forget about it until late fall..
.

Any help will be helpful.

And Happy Canada Day from up north

I agree with the advice of riding this summer and repair it in the winter. As long as it's just a few drops.

 

[ST Gui]

I had to double check and was relieved to see this was in the ST1300-Leaks forum and not Health Related.

 

[Tdinova]

Ok sounds like a plan. The weather here is terrible this past month only 5 maybe 6 days of great riding. The old 07ST has 108000km. I will ride then repair late fall. I own a service manual and it says to press out the impeller shaft and bearings. Has anyone done this uthout using the required tools?

 

[SupraSabre]

Ok sounds like a plan. The weather here is terrible this past month only 5 maybe 6 days of great riding. The old 07ST has 108000km. I will ride then repair late fall. I own a service manual and it says to press out the impeller shaft and bearings. Has anyone done this uthout using the required tools?

If you have a press, I use plastic pipe fittings, just big enough for the propeller to go through and sockets. Not that difficult, just make sure you put it back together the way it is supposed to go, and not reverse the oil seal, like I did , so now I'm waiting for a new seal before taking it all apart again!

 

[ST-Traveler]

it says to press out the impeller shaft and bearings. Has anyone done this uthout using the required tools?

Yes, and it is nerve racking to say the least. I had the round hole leak and replaced the water pump assembly. Take good measurements of how far the shaft protrudes out engine side of the impeller you will need to press in the new one at the same distance. Oh yeah make sure the sprocket drive chain does not come off the sprocket and fall down in the engine block when removing the front cover.. DAMHIK.
Since I replaced mine a couple months ago all has been good and no more leaks. This is an indication the mechanical seal is starting to fail.

 

[CYYJ]

...can I just change the antifreeze seal on the water pump or do I have to replace it all?.

I'm pretty sure that if you have coolant coming out of the round hole, a leak exists around the shaft of the water pump - the only "seal" that I can think of in that area is a very large oddly-shaped O-ring (about 10 inches in diameter, if you straighten it out). If that seal leaked, you would see coolant coming out of the right side of the front of the engine, or out of the square hole.

There are some pictures of both sides of the water pump at this post: ST1300 - Water Pump Weep Holes. The third picture shows you exactly where the round hole drains from - the shaft & bearing assembly of the water pump.

Michael

 

[Jethro]

Careful as it was said about drive chain falling off sprocket. Honda manual has no info. At that point. Slide a flat edge metal ruler between front cover and engine at location of pump sprocket to keep sprocket/ chain in place ,before separating front cover. I learned. The Hard Way! Check Stowners links for more details info!!

 

[Tdinova]

I'm looking at the service manual now. Looks straight forward

 

[CYYJ]

The disassembly to get the casting containing the water pump off the engine is pretty straightforward (a lot easier to do if you remove the front wheel & front fender first), but the process of removing the water pump from the casting and installing the new water pump is fraught with peril.

See the 9th picture down from the top in this thread: ST1300 - Clutch Replacement for a good tip about how to prevent the drive chain from falling off the sprocket.

There is also a very good tip from Larry (@Igofar) in post #13 of this discussion: Water Pump Leak Dilemma- How much is Too much

Here's some useful information about pulling the impeller and bearing assembly: New Water Pump...

Michael

 

[Tdinova]

Thanks for the extra tips CYYJ