BSMITH8315
New member
I have an ungodly amount of oil in my coolant reservoir. Like it has MORE oil than coolant. so much its not even milky in there just blue Yamalube. I have great compression, and even pressure tested the motor. Head appears to be just fine. Sled runs like a raped ape and starts every time on the 1st maybe second pull. What else could cause oil to get into the coolant? Could it leak past the water pump shaft? I have had a skidoo do that before as the water pump was lubricated by oil. Im at a loss. It is literally filling up with oil in the coolant.
drew24
New member
I know this is a dumb question but did someone accidently put oil in the wrong reservoir? I am not really sure of any other way that much oil could get in there.
BSMITH8315
New member
I thought that might be possible so I flushed the coolant system last Friday 5 TIMES just to make sure I got it all out. Beat the crap outta the sled Saturday night, ran flawless. Sunday gave the sled a an inspection and reservoir is FULL of oil....
drew24
New member
Is the level changing? I suppose if the seal is bad on the water/oil pump shaft the pressure in the crankcase could be pushing oil past the mechanical seal. That is just a thought. I have personally never seen this happen before but maybe someone else has. It would almost have to be that to get that much oil in the reservoir in that short of time. What sled is this and when you say you flushed the system does that include the heat exchangers?
BSMITH8315
New member
It has me completely baffled myself. It's a 1998 srx 700. I completely flush the whole coolant system. The only way it could get that kind of oil would be the water pump if it's lubed by the oil. I'm gonna start tearing it apart tomorrow night.
BSMITH8315
New member
Has to be getting in someplace by the oil pump/mechanical seal area like drew24 stated, I've been a yamaha sled mechanic for 25 years and never saw that issue either. I would say u have a badly worn impellar shaft,bearing and seal issue, wish I could be more help .thats my .02 cents for what it's worth.
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BSMITH8315
New member
That would be the only place i could think of also. I was hoping someone else had this happen or more suggestions.
pete_man26
New member
My question is where is all the coolant going? Is it leaking into the cases through the water pump and being replaced by the oil? Or is the coolant coming out of the overflow? Very very strange, I'm curious to know the cause.
I would check the oil/coolant plastic tank, it might be leaking
BSMITH8315
New member
Would this get oil into the coolant tank?
BSMITH8315
New member
Not sure yet.....i havent had time to rip it apart yet...been to busy hopefully next week....but im still lost
it could when it draws and moves the coolant in and from the overflow, look and see if its in the overflow bottle, there could be a crack and letting it go between the seams.
opsled
Active member
I don't see the oil injection system having enough pressure to push into the coolant system or what the path would be. If it's getting into the water pump it should be churned, mixed and milky. Your oil tank should also be emptying quickly and coolant overflow spilling out oil.
Unless this kind of stuff is happening I'm still thinking human error when filling oil tank. You said you flushed it but unless you did it with something that cuts oil you didn't get it all.
If you have oil in the coolant tank syphon it out, top with coolant and run it. Keep an eye on coolant/oil levels closely. If it was human error eventually all the oil will make it to the top of the coolant tank and be done.
opsled
Unless this kind of stuff is happening I'm still thinking human error when filling oil tank. You said you flushed it but unless you did it with something that cuts oil you didn't get it all.
If you have oil in the coolant tank syphon it out, top with coolant and run it. Keep an eye on coolant/oil levels closely. If it was human error eventually all the oil will make it to the top of the coolant tank and be done.
opsled
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