Coolant Leak ? Water Pump

[Lowside]

Howdy ST?ers. In an attempt to track down a coolant leak on my 2004 with 17k miles I stripped off the bodywork today and, within two minutes of starting the engine, found it. It?s leaking from the water pump but not from the weep-hole (upper red arrow). It?s leaking from another small opening just below and forward of the weep-hole (lower red arrow). Has anyone seen this problem before? My guess is the fix would be the same as the fix for a leak from the weep-hole. Any info would be much appreciated especially info on the procedure to remove and press in a new impeller and bearing.

Ted - Denver

 

[Lowside]

Good news I think! Some more searching revealed the below post. If this is correct then I?m in much better shape than I thought. Just need to tighten the hose clamps behind the radiator and under the tank.

https://www.st-owners.com/forums/showpost.php?p=284419&postcount=6

 

[Keith_UK]

In have coolant leaking from precisely the same place Ted, which first showed-up around mid-August last year ['06].

At the end of last summer ['06] I removed the radiator; drained all the coolant; flushed the whole system; tightened all the hose clamps behind the rad; etceteras - then refilled with non-silicate/non-borate Honda (blue-coloured) coolant. No further signs of leakage .. Great! .. until around August this year ['07], when it all returned again.

So now I'm gonna repeat the whole exercise again - AND just for good measure, I also intend to replace the water pump. Maybe this will finally resolve the problem.

Let me know how you get on with yours.

Thanks

KEITH

 

[Blrfl]

I'd bet you have a hose clamp issue. Do a search for hose clamps...Blrfl (Mark) has a solution that should solve the problem with the hose clamps.

I'm with you on that one. The lower hole is a channel that runs all the way up to the vee at the top of the engine and drains pretty much anything that accumulates up there.

Haven't tested my replacement clamps yet, 'cause I keep getting tied up with other things. Working with cold fluids in my unheated garage during the winter is not what I'd call enjoyable.

--Mark

 

[STPaulK]

I Haven't tested my replacement clamps yet, 'cause I keep getting tied up with other things. Working with cold fluids in my unheated garage during the winter is not what I'd call enjoyable.

--Mark

I was wondering why you didn't do it in the warmer months instead. I recall you saying that you were going to wait for the months when it leaked (probably to see the fix better) but I know that cooling system work just becomes that much more of a pain in cold temps.

Really, why not change them out in the warm months and then just monitor during cold months? If it never leaks again we know they worked.

 

[Lowside]

Well I spent most of the day in my cooooooold garage today. It was 21 degrees Fahrenheit when I began and warmed up to about 30 by mid day. I was able to get the radiator removed and get the five worm clamps behind it cranked down. I then moved up to the four worm clamps underneath the airbox and got them cranked down. I didn't have any coolant on hand so I wasn't able to test my work but I'm hopeful that it's fixed because this is really not a fun job a I don't want to do it again!

Ted - Denver

 

[Lowside]

In have coolant leaking from precisely the same place Ted, which first showed-up around mid-August last year ['06].

At the end of last summer ['06] I removed the radiator; drained all the coolant; flushed the whole system; tightened all the hose clamps behind the rad; etceteras - then refilled with non-silicate/non-borate Honda (blue-coloured) coolant. No further signs of leakage .. Great! .. until around August this year ['07], when it all returned again.

So now I'm gonna repeat the whole exercise again - AND just for good measure, I also intend to replace the water pump. Maybe this will finally resolve the problem.

Let me know how you get on with yours.

Thanks

KEITH

Hi Keith, when you did the work on the clamps behind the radiator did you also tighten the clamps under the airbox? If not then it's very possible your leak is from one of the clamps up there.

If your leak is from the same place as mine and not from the weep hole then I would not rebuild the water pump. It's an expensive and difficult job and likely not needed.

Cheers,

Ted - Denver

 

[Keith_UK]

Hi Keith, when you did the work on the clamps behind the radiator did you also tighten the clamps under the airbox? If not then it's very possible your leak is from one of the clamps up there.

Ted - 'No' I just tightened-up the five clamps around the thermostat housing. One of these hoses, in particular, was definitely showing tell-tale signs of leakage. In fact, I put a second clamp around this one ['to-be-sure, to-be-sure' as the Irishman said ] - thinking that this must be the source of the leakage problem.

But as I say, it's all come back to haunt me again - so it looks as though I gotta go through the whole process one more time ..

This is one hold-up I don't need as my STeed is currently in temporary storage for the winter just south of San Francisco. I'm returning there mid-March next year ['08] to ride back to the eastern seaboard before we both ship back home to England at the end of May. As I say, I don't need all the hassle before I set off from San Fran - But hey! this is all part of motorcycling ... I guess!

BTW - A new water pump is an item on my Christmas wish-list.

Please let me know Ted if your sub airbox clamp(s) turned-out to be the culprit(s). If so, then I'm likely to have a spare new water pump on my hands in just over two weeks' time - 'GOING CHEAP'...

... anybody?

 

[Lowside]

This is one hold-up I don't need as my STeed is currently in temporary storage for the winter just south of San Francisco. I'm returning there mid-March next year ['08] to ride back to the eastern seaboard before we both ship back home to England at the end of May. As I say, I don't need all the hassle before I set off from San Fran - But hey! this is all part of motorcycling ... I guess!

Hey Keith, I just reread your post and I?m envious of your upcoming US cross country ride. I wish I had time to do a European cross country trek. Hopefully soon... For your cross country trip, I honestly wouldn?t worry about your coolant loss too much. I commute on my ST every day, except when there?s snow or ice on the ground, and my bike had been dropping a flapjack sized (4-6 inch) puddle of coolant on the ground every morning for the last three weeks. I checked the coolant level every few days and it the amount the level dropped was negligible. Carry a bottle of coolant with you, check it each morning and have a great ride... and if you pass through Colorado look me up and I?ll show you the best freaking roads in the state. :yes:

 

[Lowside]

You are very clever.

Thanks BM! :clap2:

 

[Lowside]

Good news I think. I finally got a chance to mess with the bike some more last night. Put antifreeze in, ran it for about 15 minutes in the garage and no more leak. A lot of people have reported their leaks are worse during the colder months. I?m hoping that since I did this work while the temp was about 30 degrees fahrenheit the problem will be fixed for good. Fingers crossed?

Ted - Denver

 

[Mike]

Mine is in the shop for the fourth time. I know I should fix it myself but damn I have a warranty.

Once the warranty is expired I'll be glad to wrench on the bike.

I have tightened the clamps and changed out teh thermostat but the leak is elsewhere, maybe a cracked cover, bad fitting or something like that. I do hope they really investigate this time instead of just jumping on the water pump.

 

[Tor]

Good news I think. I finally got a chance to mess with the bike some more last night. Put antifreeze in, ran it for about 15 minutes in the garage and no more leak. A lot of people have reported their leaks are worse during the colder months. I?m hoping that since I did this work while the temp was about 30 degrees fahrenheit the problem will be fixed for good. Fingers crossed?

Ted - Denver

Sooo,,are we still watertight?

 

[Mike]

Got my ST back today. They replaced the waterpump again and the bearing, said the bearing had a flat spot in it.

Next few days will tell.

 

[jerry]

what is the weep hole for? is it for expansion?

 

[ccryder]

One hole is for any leakage by the water pump seal. The other hole is a drain from the area in between the cylinder banks.

Neil S.