crank seals ... when to change????

[danduvall]

i pulled my motor on my 2006 900 SB to change my stator. and found that my crank seals were wet with oil, at the end of last year i pulled my clutch and the pto seal was just barely damp, i wiped it off and rode the sled maybe another 75 miles and no more oil appeared! when i pulled my flywheel this is what i found...

i dont know if this little bit of oil is normal? should i replace the seals while the motors on the bench? i dont WANT to change the seals, but i really dont want to replace crank bearings either.

sled has 2200 mi, plugs were burning great, piston wash was perfect! so it didnt seem to be running lean. also, no apparent damage to the seals, what do you guys think? how often do you all change crank seals?

 

[danduvall]

Anybody?!?

 

[faulk222]

just my 2 cents any sign of oil outside means air can be sucked in and seals should be replaced to prevent running lean on that side

yes you need to remove engine

seals and a bit of your time is cheeper then replacing min 1 piston 1 cyl and whatever else the piston damages

Tren

 

[danduvall]

are the crank seals on our 900's the type with the raised ridge around the outside that locks into a groove in the crank cases? or are they smooth, allowing me to change them without splitting the cases?

 

[Super Dave3]

The case will need to be split to replace the crank seals. IMO with that small amount of oil I would not go to the trouble to replace them.

 

[faulk222]

The case will need to be split to replace the crank seals. IMO with that small amount of oil I would not go to the trouble to replace them.

just thaught it would be safer since the engine is on the bench for the price of the seals its peace of mind imo

Tren

 

[Danbot]

Dan... do you have access to crank case pressure testing equipment? If not it can also be made from hardware store parts. Any 2 stroke engine should really be pressure tested after assembly, and it would work well to determine the condition of your seals.

 

[danduvall]

Dan... do you have access to crank case pressure testing equipment? If not it can also be made from hardware store parts. Any 2 stroke engine should really be pressure tested after assembly, and it would work well to determine the condition of your seals.

ya know you're right! i think im going to acquire some leak down test gear this week and give her a good pressure test before i replace the seals, plus im starting to wonder if the liquid is actually gummed up coolant from my overflow hose dripping into the recoil housing! although it didnt taste sweet, it did have a green hue to it!

 

[Danbot]

ya know you're right! i think im going to acquire some leak down test gear this week and give her a good pressure test before i replace the seals, plus im starting to wonder if the liquid is actually gummed up coolant from my overflow hose dripping into the recoil housing! although it didnt taste sweet, it did have a green hue to it!

And on that note.... SAVE YOUR STATOR!... put heat tape over that upper hole at the recoil housing.
I think it cost me about $30 to build a good tester last year (with enough plugs and adapters to work on all sorts of different sizes of engines)

 

[danduvall]

Stator is already toast. That's why the motors sitting on the bench. Coolant ruined the epoxy on my inner flywheel ring.

 

[faulk222]

that sucks same thing happened to me couple years ago but the magnets stayed in place so i glued it back togather and replaced stator and TAPED THE HOLE

Tren

 

[danduvall]

that sucks same thing happened to me couple years ago but the magnets stayed in place so i glued it back togather and replaced stator and TAPED THE HOLE

Tren

My magnets stayed in place as well. I really want to try gluing my inner ringg back in! How did that work for you? And what epoxy did you use??

 

[faulk222]

not sure the name it was an industrial epoxy i live in a mining town where industrial prodocts are available and sometimes (which in this case) do not have markings because they came from a "kit" for something but it has not moved in 2 seasons so with a good glue it can be saved if the magnets have not moved

any good epoxy should hold it in place as long as the magnets have not been hurt or damaged

Tren