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Collant Weeping out of weep hole, water pump seals?

17K views 26 replies 5 participants last post by  nolanator 
#1 ·
So my bike has always left a small oil spot on the ground after my ride to work. It drips a couple drops from the vent hose, and my tranny seal. But it started dripping a milky looking substance. The oil on the dipstick is clear and still looks good. I was thinking it might be just a mix of the normal oil drip and how wet it has been lately, lots of fog and some rain. But then I noticed that there was a small amount of coolant leaking from the weep hole by the water pump. Got on thumpertalk and it says that is the sign when you need to replace the oil seals on/behind the water pump. But it doesn't seem like it drips every time, thumpertalk also mentioned some stuff about when its colder the seals shrink and will leak some until warmed up. How worried do I need to be (priority of putting new seals in?) So how hard is it to replace these seals?
 
#7 ·
And on a side note...Those crankcase breather tubes...oh how I hate them. I sank my bike up to the tank in October of 06' in a mud hole. Bike stalled. That fucking tube sucked up at least a pint of sludge from that puddle. I am not sure if it did the sucking when it stalled or as I was kicking the bike after we got it out but that little escapade cost my insurance company $3500 for the new motor. Yamaha does not sell a complete motor, you have to buy parts. :headshake

My breather tube now runs into my airbox with a filter on the end and a "T" near the shock that goes down and drains with all the carb vents.:thumbup: And because of this new path the tube takes most (all) of the oil that gets spit out drains back into the motor.
 
#11 ·
I pulled the clutch cover on mine and did both seals (oil and water). Glad I did as the oil seal was shot.
To do them both You have to remove a bearing from the clutch cover to acess the oil seal. I just used a scotch brite pad to clean up the impeller shaft. It felt grooved until I cleaned it up by hand and is holding steady with no leaks. I believe the "groove " was caused by deposits left from the seal. It is a "stepped" design so there will be a groove where it is machined naturally. I Was careful when removing the old gasket from the clutch cover as I wanted to re-use it ($22 from yamaha). I just sprayed it down with contact cleaner before reassembly and its not leaking as of yet.

 
#14 ·
So my question is I know I need to replace the 2 water pump seals. However I don't have the $100 right now to replace the seals, impeller, shaft, bearing and oring. Am I ok to ride it as long as I keep and eye on oil and coolant? Hold off till after the holidays and do it all. Or just order the seals and do the seals now, and possibly have to go in to replace the impeller and shaft later.

It is my sole mode of transportation so I would rather fix the problem right if it is going to cause catastrophic problems. But if it is harmless to let it weep for another month and a half then I would rather do that and put all new parts in.
 
#15 ·
You shouldnt need an impeller. My opinion is to replace the seals. If everything goes south and you have a catastrophic failure now your out $1500 for the whole motor instead of $100. I did both seals and the shaft and I think it was $40
 
#16 ·
So is seams as thought the milky oil is getting whiter...more water in it. And it is coming out of the crankcase vent tube. Where before I thought it was just mixing on the frame rail from the weep hole and vent tube.

So if it is coming out of the crankcase vent milky...do I have a bad head gasket? But on the dipstick the oil looks normal, and I changed it on Monday and there was no sign of water in the oil that drained out.

Will bad water pump seals also cause this?
 
#19 ·
It's not that big of a job. Id do it for free if you brought a case of miller lite lol. One suggestion an experienced engine builder gave me was to coat both sides of the new hg with "super 300" gasket maker. He said he uses it on most hg's. It seems these engines are somewhat known for hg failures. Look at my top end rebuild thread in the yamaha section.
I bought a numera top end gasket set from eBay for $29 shipped. It was good quality, came with a metal base gasket and valve stem seals.
 
#20 ·
So just kind of thinking out loud and looking for someone with more knowledge and experience than me.

Ok so I know that the water pump seals are bad because its drips out of the water pump weep hole. So yes there is a coolant leak.

But if it were a head gasket wouldn't there be oil either on the dip stick, or in the oil when I drain it? Also wouldn't there be some white smoke (water being burned) coming out the exhaust, especially on start up? Also if head gasket wouldn't I be having some compression/power loss?

Also another thought. I noticed the milky oil drips a couple weeks ago. Around the same time our weather changed. We get heavy fog in the morning, temps dropped, more moisture in the air in general. So could it be that condensation from the air, or forming in the vent tube is causing the oil to turn milky that drips out of the vent tube?
 
#21 · (Edited)
its not uncommon for there to be "milky oil " in a vent hose. Thats what is there for- to remove excessive pressure and condensation from the crankcase due to temp changes etc. I misread your last post thinking you changed the water pump and oil seals and it progressivly got worse but I see now that you just changed the oil. I would do the oil seal behind the water pump asap as well as the water pump seal. It's a cheap and easy repair that a small shop would probably charge less than $100 to do. Depending on how severe of a leak it is if any is irrelevent as water can cause catastrophic damage to bearings even in small amounts. Your water pump seal is leaking if theres water coming from the weep hole. It takes another $4 to replace the oil seal behind it that keeps water out of your crank case.
 
#23 · (Edited)
fwiw you could replace the water pump/oil seals for as little as $10 if the impeller shaft is ok, $40 if not. A hg will not always smoke, show excessive amounts of water in the oil, oil in the water etc. It can be a small leak around a water jacket that just adds excess pressure to the cooling system by letting exhaust gasses into the cooling system. This is somewhat hard to diagnose in its early stages and usually takes a special cooling system tester to detect the presence of exhaust gases. You have to remove some coolant approx 2" from the top of the radiator then place the tester (looks like the pump to a blood pressure cuff you dr uses) into the neck of the radiator opening and it sucks air from the radiator- the tester has a blue dye in it that turns to an amber color if gases are present in the cooling system.
 
#24 ·
The seals are on the way $10 for both. Hopefully my impeller and pump are good.

My buddy was saying that I may be able to take the rad cap off start the bike and look for bubbles. I'll do that tonight. If that doesn't work I and it still shows signs of possible HG after I do the seals I may take it somewhere for the test you described.
 
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