Howdy..I have a 99 vmax sx600 triple with a coolant leak. I'm getting a steady drip coming out the bottom, around the skid plate, with nothing visible at all from the top. Talked to our local dealer and after explaining the situation to him was told it's probably the cooler having a crack in it.. ...decided to tear into it several weeks ago..pulled the motor and found the hoseclamp on the cooler end of the hose, coming from the waterpump to the cooler, 2 inches back from the inlet..the clamp was totally not even on the cooler inlet at all..like the hose was just pushed on and they forgot to put on the clamp... .so..we're all happy thinking that's gotta be it..put it all back together...still leaks!! Where I am now is thinking to just put some radiator sealer in and try to make it thru the winter and tear into it next year. Seeing how everything has to be removed beyond the motor-jackshaft, clutches,etc., then drill rivets and remove that metal plate that covers the cooler.....seems very painful...and ..might I add..incredibly stupid design for Yamaha!!.. this is more of a wife/backup sled now so I'm a little more inclined to just try to get by for now...thoughts on this anyone...what type of sealer?..no sealer at all?...trade it?...apply fire and roll it down a hill?. .???? ...And please..no bashing about not caring if I leave my wife stranded!!!! :smilielol:

Still getting a steady drip? Then it can't be too hard to actually find the actual source of the leak. If you're confident it's the cooler itself, I'd highly recommend you replace it.

If it's a steady drip while cold, it will be a very fast leak while under heat/pressure. And the leak may get worse when you're not looking.

Obviously i'ts your call, but if you think replacing a cooler is an expensive PITA, remember it's cheap and easy compared to overheating your motor...

Fix it now, fix it right or get rid of it! You will thank yourself in the end.

I would not use a cooling system sealer in any sled, the passages are just too small in the coolers to run the risk of plugging them up with a sealer product.

Pull the motor and rig up a section of pipe & hose ( with a schrader valve ( tire valve ) fitting ) and connect the cooler hose's together, apply a little pressure with a bike tire pump to see where the leak is.

If the leak is in a cooler a good welder can weld it up with little problems!

I have done trail side repairs of coolers that were punched thru from a stud using JB weld or something similar that have held up for over three years now, so that is another option! But welding is always a better option!

I agree...though my first post referenced REPLACING the cooler (sometimes they're cheaper to buy than you think), there is absolutely no reason why a cracked/broken/hole punched in an aluminum cooler can't be cheaply REPAIRED by any barely qualified welder, or even by any well trained monkey given the correct epoxy and the proper surface prep.

So unless the leak is from the engine block itself, this will likely be a very inexpensive and permanant fix. Access and locating the leak is the only challenge, and those cost nothing but a few hours of time and some skinned knuckles. There's no good reason to let it continue leaking, or to install any type of sealing product to the coolant (which incidentally will NEVER work as advertised).

What he said!

Those motors are notorious for the water seals going bad in the water pump. If the motors still out of the sled, it's a pain, but a lot easier than when it's still in the sled. Remove the waterpump cover, pry the old seal out and install a new one. Also change the o-ring on the impeller bolt. Be careful not to scratch or mar the pump housing when prying out the old seal. Use a socket or pvc piece a bit larger in diameter to tap the seal back into the housing.

Hope this helps,
Jon

Fixed a lot of these, I would bet anythng it's the water pump. You have to getthat fixed because it is also leaking inside the case and contaminating your crank (most of the time). You can pull it with the motor in the sled but it's a pain. If you have never done it I doubt you wil be able to do it in the sled. The seals can be a real bitch to remove as they are pressed in and have a heat sealer on them. Be very carefull when prying them out so you don't scuff the sealing surface on the edges. Also DO NOT TOUCH the new seal with your bare hands (the little white one) for some reason it will ruin it. You will also most likely need a new water pump shaft also. This is what most likely cause it to fail in the first place. The shaft is not stainless so it corrodes over time and acts like a saw and chews up the seals. No amount of cleaning or polising will fix it. It is also the same shaft that drives your oil pump. It goes all the way through the motor and is driven by a brass gear. My suggestion is pay the 300.00 to a shop and get it done right our it will leave you on the trail and wreck your ride and friends ride for the weekend. Don't forget to get a new water pump cover seal as well that rubber O-ring gets corroded also and the sealing surface will need to be wire brushed and prepped as well. doug

Start drinking heavily... :drunk:

When riding my Viper my coolant would drop, but I never saw any leaks or drips. Pressure test showed the leak from the water pump, which as stated was common problem. My buddy did the work, but it was a pain in the butt, especially getting the old seal out. If had to do again, I'd probably just take it to the dealer. Soon as the snow comes back we'll see how it goes.....Good luck!

Posting an update..several weeks ago we took off for Illinois to big river state park cuz they had a little snow left and I wanted to get a chance to see how things were gonna work with my new machine and the yammie.. .-I had not put any sealer in it yet at that time- we got there and I decided we're just gonna ride and see how bad it leaked. .. we started riding after topping everything off and rode for about 2 1/2 hours .. ..stopping and cheking every so often and no green mess underneath..reservoir not going down. .nothing. ..rode , cheked, rode, cheked,,.. . .. rode and cheked..not one leak, reservoir stayed exactly where it started!!! ... .I'm like totally happy ... .the only thing we could think of is that when we initially started it after getting the motor back in we didn't run it for more than a couple minutes and saw coolant dripping out again and shut it off right away... there must have been enuff residual coolant left somewhere down in the pan or elsewhere and that's what we saw dripping out only we didn't run it long enuff for it to totally dry out. ..so it must've been the hose connection after all!! Yeeehaaaa. . .thanks be to God!!! .. .. .now......SNOW!!!!!!!!!!!!!!!!!!!!! :banana: