Odd Scrambler problem, failed oil injection?

[Blown 331]

So today a buddy of mine was using my main Scrambler to pull start an XT500 I just bought. He said it lost power and died almost like it was flooding out. I tried a bunch of different spark plugs, choked it by hand, shot gas in the back of the carburetor, and it had plenty of compression. You could clearly feel compression strokes when pulling it with the recoil. And when cranking with the starter it would blow my thumb of the spark plug hole. It also had nice blue spark. So I had compression, spark, and fuel, but it still would not start. I poured a little transmission fluid in the spark plug hole and it fired right up and ran great. I'm guessing the transmission fluid helped the Rings seal better, but it really did have good compression before that. So was the cylinder not getting enough lubrication? I guess I'm going to start premixing that 1 too. Thoughts?

[200xranger]

my blaster i had years ago did that. oil line or something got clogged and quit oiling. sounds like your buddy got the flooding/bogging idea mixed up with a lean bog. i premixed from then on out without doing the block off and the oil level in the tank never dropped. i was lucky and caught it in time before damaged occurred. hope it helps

[jeswinehart]

I hafta admit the diameter of the hose, on the vent tube, of the Polaris trike scramblers 2 stroke oil tank is certainly the smallest possibly ever used. I owe that skimpish oil tank vent tube 1 top end (when it plugged up from lake snow/ice tire spray while crusing a local frozen lake 4 years ago).
I tend to think your machine flooded out, fluids in crank case. IMO the tranny fluid only helped to pull vacuum (which is a great trick :) ).
I believe if you pull the crank case drain plug (special hole for that in front skid plate) you will get any where from a thimble to a cap full of fuel out of it and it will start.
About a thimble full or more of fuel/oil mix in crank case of a P-3 and they will not start for love nor money.
I am running premix in mine only because I was (still am) more confident in my 100 to 1 Amsoil mix ration then a mechanical and/or skimpy arse vent hose.

[Blown 331]

All good suggestions! My oil tank vent is clear and 1 of the first things I did was pull that crankcase drain, not a drop came out. I forgot to mention the drain.

[keister]

I have never relied on this system. I always run pre-mix (around 40:1). Same fuel I use in my 250R, chainsaw, etc.

John, you run 100:1??

My plan is to thoroughly clean my oil injection tank, add a petcock, and dispense tasty beverages from it on the trail.

[Howdy]

While I have all my injectors hooked up, I do run mixed gas in the tank as well. The gas is probably mixed 100-1 ( just poured a little in the tank for safety ). I do know the oil is going down in the tank, but a little insurance can't hurt.
Howdy

[CRAZY70MAN]

I have never relied on this system. I always run pre-mix (around 40:1). Same fuel I use in my 250R, chainsaw, etc.

John, you run 100:1??

My plan is to thoroughly clean my oil injection tank, add a petcock, and dispense tasty beverages from it on the trail.

Awww ya Peepers!!! Great idea!! I must do that on mine as well!! Yeager tank!! I do however run 32-1 in mine premixed. She really does not get much use though. Just around the yard.

[jeswinehart]

154422154423

Works great !

[hillbilly 200x]

So today a buddy of mine was using my main Scrambler to pull start an XT500 I just bought. He said it lost power and died almost like it was flooding out. I tried a bunch of different spark plugs, choked it by hand, shot gas in the back of the carburetor, and it had plenty of compression. You could clearly feel compression strokes when pulling it with the recoil. And when cranking with the starter it would blow my thumb of the spark plug hole. It also had nice blue spark. So I had compression, spark, and fuel, but it still would not start. I poured a little transmission fluid in the spark plug hole and it fired right up and ran great. I'm guessing the transmission fluid helped the Rings seal better, but it really did have good compression before that. So was the cylinder not getting enough lubrication? I guess I'm going to start premixing that 1 too. Thoughts? You could have sized the rings to the piston. Take the carb off and see if it has any suction through the intake when you turn the engine over , no suction no good

[Blown 331]

It runs great so I don't think the rings are stuck.

[Blown 331]

It runs great so I don't think the rings are stuck.

I may have spoke too soon on the running great part! I used it for a hour or so the other day with the oil injection back on and 32:1 premix in the gas tank. It would randomly just die and not restart again. But when it ran it was running great with the premix, definitely more power than without, I guess it was starving for oil?
Last night I couldn't get it started so I pulled the top end. It looks like the original piston, no wear on the cylinder, rings not stuck. It did look like a bit of compressoin had been leaking passed the rings though. I'm also 99% sure the base gasket was blown, kind of weird. On both sides of the base gasket the gasket was oil soaked all the way through and seemed brittle in that area. I'm thinking of just going with a standard bore Wiseco but I want to measure everything up first.

[Howdy]

Check out sledpartsguy on feebay for good deals and customer service. I get all my P3 topend stuff from them. I have their web site saved if you need it.
Howdy

[Blown 331]

I actually just ordered it from them! My cylinder has no ridge and its measuring out good so I went with sledpartsguy's Wiseco standard bore topend. Piston, rings, pin, bearing, cips and gaskets. Already got the tracking number, should be running rather quickly. Hopefully the base gasket was the problem, it would suck if it still didn't run after I got it back together!

[Blown 331]

Its back together with the new Wiseco and running great! The oil injection is working but I think I'll run a bit of premix just to be safe. And now I have the peace of mind of knowing I have a new top end.

[M.Pargiello]

I noticed the oil injector in mine wasnt working VERY quickly after the first rebuild :)

Needless to say, there is a new top end on it and nothing but premix. My brother wants to snorkel it through the original oil tank location :D