Water Pump Weeping after 160,000 Miles

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Ignacio

Intramural Culture Warrior
Staff member
Joined
Jun 28, 2005
Messages
9,429
Reaction score
2,772
Location
Tri-Cities, WA
While doing some maintenance the water pump has been weeping signficant amounts of coolant from the weep hole. Fortunately, I have a spare 60K FJR that's effectively turned into a parts bike 10 feet away and did a swap. It was a 5 minute job with plastic off and o-rings all were good to go.

I guess they don't build them like they used to. Only got 160,000 miles out if this one!
wink.png


 
Last edited by a moderator:
Matt, that is not atypical for any bike's waterpump. There is a mechanical seal for the pump shaft that often fails by weeping from the drain hole. It is basically a smooth spring loaded ceramic disk that another disk on the pump shaft contacts and spins against.

There are actually two seals, the mechanical coolant seal on the outer (water) side, and another, typical oil seal on the inner (oil) side, separated by a small space, and that is where the weep hole drain is, in between the seals. Ypou can go a long way on a weepy pump seal as you never really lose all that much coolant and it is unlikely to just rupture completely and gush all your coolant on the side of the road.

But changing the seals (I'd go ahead and do them both since you'll have the pump off and apart) is not a very big deal. Just did one on my Man'Strom about 6 months ago, but they are all pretty much the same basic design.

 
Last edited by a moderator:
Ypou can go a long way on a weepy pump seal as you never really lose all that much coolant and it is unlikely to just rupture completely and gush all your coolant on the side of the road.
Concur. I think it started weeping over a year ago. Just a bit and I watched during the IBR.

However, there had been substantial puddles the past month or two, reservoir was empty, and thought it prudent to swap out before I wander off to Nevada this weekend for a REALLY BIG ride. ;)

 
I looked pretty carefully at the water pump on Patriot's ruined motor and it was leaking. The mechanic felt certain of this also. I believe that engine was around the 160K mile mark also.

160K miles would not be considered too early for an automotive water pump to go out in my mind. My truck redlines around 3K and my wife's car around 6.6K but they seldom spin anywhere near their redline. When I consider the 9K rpm redline on the FJR and how often it is spinning into its upper rev range, I think 160K miles is pretty darn good.

I am guessing Ignacio is not really that unhappy with 160K. I personally wish I had time to put anywhere near that many miles on my bike.

 
Last edited by a moderator:
Yeah, I get it... only 160k? What POS.

Now you're going to have to invest 20 or 30 dollars worth of easy to get parts and an hour or two of labor on that near virgin bike.

It was probably caused by the oddly clashing (Michigan) colors you painted it with. That would foul any seal.

See what I mean?

seal-wcamera.jpg


 
While doing some maintenance the water pump has been weeping signficant amounts of coolant from the weep hole. Fortunately, I have a spare 60K FJR that's effectively turned into a parts bike 10 feet away and did a swap. It was a 5 minute job with plastic off and o-rings all were good to go.
I guess they don't build them like they used to. Only got 160,000 miles out if this one!
wink.png
That is a lot of miles. Sounds like a good design to me. Oh, sounds like your weep is a drip.

 
Nice. My Street Triple lost it's seal at 21k miles and was one of the many reasons why I traded her in for my FJR.

You had to drop the headers and pull the oil pan as the pump was buried inside the oil pan. Not a five minute job.

 
Last edited by a moderator:
Matt, that is not atypical for any bike's waterpump. There is a mechanical seal for the pump shaft that often fails by weeping from the drain hole. It is basically a smooth spring loaded ceramic disk that another disk on the pump shaft contacts and spins against.
There are actually two seals, the mechanical coolant seal on the outer (water) side, and another, typical oil seal on the inner (oil) side, separated by a small space, and that is where the weep hole drain is, in between the seals. Ypou can go a long way on a weepy pump seal as you never really lose all that much coolant and it is unlikely to just rupture completely and gush all your coolant on the side of the road.

But changing the seals (I'd go ahead and do them both since you'll have the pump off and apart) is not a very big deal. Just did one on my Man'Strom about 6 months ago, but they are all pretty much the same basic design.
This stirred some (very) distant memories about mechanical seals but I just couldn't remember what this type was called. Woke up this morning and hey presto It all came back. I believe you are referring to a Crane Seal (or some variation of it). These things have two great characteristics; high reliability and very easy to replace.

 
Top