Water Pump Mechanical Seal

[1500Rider]

Been doing some searching on the site and just wanted to check with those who have more experience with this issue before I commit to ordering parts.

The other day I was doing some work in my garage when I noticed a small wet patch on the concrete below my Valkyrie, maybe two inches across. After inspection, I determined it was coolant (I use Evans).

The bike was parked on its center stand so was sitting level and the spot was directly below the water pump. At first I though it might coming from the drain bolt but that was dry. Closer inspection revealed that the leak was where the pump in inserted into the engine block. There is a shroud on the front of the engine surrounding where the water pump is installed and the coolant was concentrated there. Looking at the shop manual, this is the area Honda tells you to inspect and should coolant be there, replace the pump as a unit.

Reading through numerous posts on this site, a common source for coolant leaks are the hose clamps. I have ruled those out as all are dry. There is no coolant running down from any point above the water pump. The manual states that if coolant is present in the inspection area, the mechanical seal on the water pump is compromised requiring a new pump. I'm assuming the mechanical seal is not either of the o-rings shown on the parts diagram under Water Pump on the various websites I've looked at to source parts – is that correct? The two o-rings don't look to seal the area that's leaking. One appears to seal the water pump housing and the other, an oil seal where the pump is inserted into the engine block.

To further test the system, I dried the area that had coolant on it and started the bike. After letting it run for about 20 minutes, I've parked the bike and put it back on the center stand. Initial inspection while the bike was still warm did not reveal any additional leaking, however, I will wait until it cools fully to see if a leak develops once the metal contracts.

I really don't want to order a whole new pump unless necessary, however at this point, that appears to be the problem.

Any thoughts?

Thanks in advance

[BobB]

I had the coolant pump fail several years ago.  There is a rectangular weep hole under the pump right where you have suggested the leak is.  If that is the case, yes, the pump must be replaced.  Only Valkyrie pumps can be used, Goldwing pumps are different...

[1500Rider]

Thanks Bob – that's kink of what I figured. I should mention that after running the bike and allowing it to cool, there is, so far, no additional leaking.

The initial leak showed up after the bike had been stored for the winter and after I had pulled it out and started it up for about 10 minutes. It was about a week after this that I first noticed the spot on the floor. At that point it still hadn't been ridden yet this season.

I'm going to leave it a few more days to see if the leak reoccurs. I was wondering if allowing it to run for so long the second time may reseated something that might have not been quite right after sitting so long over the winter months. Probably wishful thinking on my part!

Maybe the best thing to to is take it out for a ride and see what happens. So far I haven't had the chance to ride it this year. Maybe that's all it needs.

[Bone]

I'm in Michigan different bike a 4 cylinder Aspencade. The bike had it's winter storage in an unheated garage. First startup several years it would leave a small coolant spot. Didn't show after the first start.

Good luck. 

[Hook#3287]

I'm in Michigan different bike a 4 cylinder Aspencade. The bike had it's winter storage in an unheated garage. First startup several years it would leave a small coolant spot. Didn't show after the first start.

Good luck. 

What bone stated happens quite often at the beginning of the season or when it starts to get cold again. Valks will sweat a little coolant. I would give it some time and see if it stops on its own.

If you find you have too, changing out the pump is pretty easy, just remember to drain the motor oil.

[BobB]

I believe you are right about riding it.  When the pump fails, as mine did, it is a considerable amount of fluid.  The weep hole is there to insure that coolant does not migrate into your engine oil when the internal pump seals fail...

[1500Rider]

Thanks for the replies everyone. So far, so good. No new leaks after running the bike. Going to take it out for a ride soon and check it again. Hopefully whatever it was has corrected itself.

[Curly]

Hi guys.
I have noticed a small coolant leak under my 1998 Valk also. Sometimes it's there, sometimes not. The bike gets ridden frequently as I live in sunny Philippines. I will certainly check the top hose for leaks as I note the previous comments that have been made about this issue. Unlike before - the bike now requires a coolant top-up of about 1 inch every couple of weeks/400Miles when ridden in heavy traffic in searing Asian heat!! It didn't need this before though...

My trusty mechanic here is adamant I needed a new 'Mechanical Seal". Obviously I will double-check for leaks elsewhere but if he's right - I can't seem to find any information on buying a replacement Mechanical Seal for the bike? Can it be ordered or does it come as part of a new Water Pump? 

Either way, if I need to replace either the Mechanical Seal OR the Water Pump - does someone know where I can order it AND the correct Part Number(s)? It's a standard 1998 GL1500 with 65,000M ODO. I will need to ship it of course...

I am assuming that the Mechanical Seal comes included if I bought a complete new Water Pump? Does it?

Any helpful 'pointers' would be great. I can ride my new Valk, but the old bird is still the best for long trips

Thanking you all in advance & Merry Christmas folks!
Curly.

[Skinhead]

Check the lower rad hose clamp as well.  I've found it leaks more often than the upper.  If it is a recurring problem, I suggest replacing the skinny OEM Honda clamp with a full size automotive clamp.  It will provide more sealing surface area.

[Chrisj CMA]

When the upper hose (at the thermostat) leaks because of a loose clamping (fairly common) there is usually only a trickle and it terminates at the water pump area. 

I would use a flashlight to look up forward of the carbs on the left side. After you see it with the flashlight it will be easy to tell if it's shiny=wet or dull=dry

[indybobm]

If you have not done it yet, it might be a good idea to try to tighten the bottom of the upper radiator hose where it goes into the thermostat housing.

[Hook#3287]

My trusty mechanic here is adamant I needed a new 'Mechanical Seal".

Is this another name for o-ring?

I would identify where the leak is starting.

If at the end of any of the hoses, easy fix, usually.  Tighten or replace the clamp(s).

If from the weep hole of the water pump, you need a new pump.

https://www.partzilla.com/catalog/honda/motorcycle/1998/gl1500c-a-valkyrie/water-pump

You'd also want #12 and #3 wouldn't hurt either.

[Jruby38]

Hi 1500,  Been there. $150 for a new pump I thought was leaking out the inspection hole,  and 50 cents for a c clamp to fix the  actual leak on the pump top hose.  You cant see the top unless you remove the pump. Try new c clamps first.  Cheep try.

[SCain]

When the upper hose (at the thermostat) leaks because of a loose clamping (fairly common) there is usually only a trickle and it terminates at the water pump area. 

I would use a flashlight to look up forward of the carbs on the left side. After you see it with the flashlight it will be easy to tell if it's shiny=wet or dull=dry

This is a very common problem, you have to pull the radiator forward to get a good look at the upper radiator hose at the thermostat housing.