The dreaded RV crank seal leak......

[68ragtop]

Hi Guys, I bought a pair of older 580 ski's that have been sitting for 2-3 years, & I bought them in non-running condition.
One engine turned out to have a rust seized starter. After installing another working starter, I pulled the plugs, inspected the cylinders with a borescope and then sprayed a little oil in there & manually rotated the crank. Everything felt & looked good, so I spun it over with the starter.
Within 10 seconds of cranking the PTO side started to spit some oil. Not enough where I feel it would have hydro locked, put it was more than just a little. As soon as that ended, I put plugs in it & fired it up. Smoked like crazy as I expected. In the end there was another small puddle of oil on the shop floor out of the exhaust. I would estimate that all said, it was probably had at least few table spoons or more of oil passed through it.

So....... I realize its the RV crank seal leaking, But Not sure this leak warrants pulling the engine apart?? It took 2-3 years of sitting (with the oil tank half full) to get this oil pushed past the seal. The crankcase wasn't full or I would have had way bigger problems, but its definitely leaking.
What’s typically seen with these slow leakers? I would imagine many people have slow leaks that only show their symptoms the beginning of the season? Maybe some that don't even realize they are leaking at all? What would you do with it?

Thanks for your thoughts!

 

[donkey]

i have one that is leaking,about 1/4 inch a week(black marker on the oil tank).runs perfect other than smokes upon initial startup.yes it will need a rebuild.no i wont do it till there are other reasons.so.id run it

 

[Spimothy Leary]

donky is right,,,
it will smoke on startup after sitting a few days, then shortly after, the smoke will clear out and your enjoying the water.

i would not tear down an older engine like that without a better reason, this isn't nearly enough to warrant that.

enjoy the ski !

 

[mikidymac]

That much oil in 2-3 years is just fine. Run it and keep an eye on it. It could get worse with use but could get better too as it is run.

 

[68ragtop]

Thanks guys, I feel better about it now. I am a longtime 2-cycle guy, but have never worked on these seadoo engines, so I am still learning their nuances.

I am also going to rebuilding a 580 White engine next week, I decided to test the seals to make sure I can use the crank as is. I hooked up a line on each side of the RV chamber & attached a clear tube. Got all the air out of the cavity & marked its current fluid level. I also filled it with ATF, I figured If these seals leak, I am going to find out faster with ATF. A handful of drops past the seals & I should see it in the tube. I suppose I should probably expect some, but over how much time?

I would imagine with the oil tank in the ski mounted higher than the engine block & full to capacity, there will be more pressure against the seals than what I am doing here, but at least it should give me some idea..

 

[Spimothy Leary]

Thanks guys, I feel better about it now. I am a longtime 2-cycle guy, but have never worked on these seadoo engines, so I am still learning their nuances.

I am also going to rebuilding a 580 White engine next week, I decided to test the seals to make sure I can use the crank as is. I hooked up a line on each side of the RV chamber & attached a clear tube. Got all the air out of the cavity & marked its current fluid level. I also filled it with ATF, I figured If these seals leak, I am going to find out faster with ATF. A handful of drops past the seals & I should see it in the tube. I suppose I should probably expect some, but over how much time?

I would imagine with the oil tank in the ski mounted higher than the engine block & full to capacity, there will be more pressure against the seals than what I am doing here, but at least it should give me some idea..

ya my buddy (he's the wrencher, not me, i'm just full of hot air) does that...

i remember asking him why the hell he was hanging stuff on a hook above an an engine, and essentially if i remember correctly, he looked at me like I was stupid and said he was "checking the crank seals"

anyways, sounds like your on the right track.