Stupid two-stroke question - it's been sitting for a while

Discussion in '2 smokers' started by Tinker1980, Jan 24, 2014.

  1. Tinker1980

    Tinker1980 Doesn't ask why, only asks how

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    This isn't exactly a bike... or old school... but you can ride it, and it's a two stroke, so here goes.

    I have a polaris trailblazer 250. I'm in the process of getting it running/rideable again since my idiot son ran into a truck with it.:rofl It's been sitting a while, and when I went to look at it, the fuel petcock had been left open.

    I managed to get it to start, and after a minute of holding the throttle partially open, causing smoke to billow out of the shop, the engine settled down and (sorta) idled. This is when I noticed gasoline/oil mixture pouring from the flywheel cover. I turned it off, since dying in a conflagration isn't something I felt like dealing with at that time.

    So, my stupid question is as follows - what's going on here? The crank seals are new. Was the crankcase just full of fuel? Do I need to man up, and just run it until it stops dripping? Should I turn it over on it's back, remove the carb and spark plug, and turn the engine over until it's empty, and then try again?

    A little history on the engine in case it helps - it is supposed to have a oil-injection system, but since it stopped working on me way off in the woods one day and burned up the rings, I have capped off the lines and been using pre-mixed fuel at 40:1. It has a very recent (Less than five hours) top end rebuild on it, with a 1mm oversize.

    Oddly enough, the only problems I've ever had out of this american made machine, is the JAPANESE engine. *cough*
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  2. concours

    concours WFO for 44 years

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    That Fuji engine, is a fine one. There is a Phillips head drain screw under the crankcase, so you can see if it has gas in it. What else is in the flywheel cover? (plumbing)?
    #2
  3. Duck_Pilot

    Duck_Pilot Retired Roadracer

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    Premix may not be a grand idea. By pouring oil in the fuel, yer jetting has become lean. And if the crank has slingers to retain injected oil on the main bearings, then the premix may not reach 'em.

    You may have opened a nice can 'o worms. Proceed with caution, and find an expert on that particular engine before going much further.
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  4. Motopsychoman

    Motopsychoman Not a total poseur

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    Likely the crankcase WAS full of fuel and the hydraulic jacking blew the seal out when the piston came down. Pull the flywheel off and take a look.
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  5. Tinker1980

    Tinker1980 Doesn't ask why, only asks how

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    Um... no. The little pump that used to mix oil into the fuel took oil from a tank in the front of the machine, and pumped it into the carb. It didn't pump that oil into the crankcase. Furthermore, it's been running for a couple of years like this, without any ill effects. It's quite a common modification to this ATV, for people who don't want the oil injector pump to fail 5 miles back in the woods.

    Concours, it's cold outside at the moment so I'm not out there looking, but can you reach that screw with the engine in place?

    The only thing on the flywheel side of the engine, are the pull-rope starter, the flywheel, and the magneto. No plumbing or anything else, thank goodness. It's actually a pretty simple engine.
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  6. Duck_Pilot

    Duck_Pilot Retired Roadracer

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    Glad to hear that!
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  7. concours

    concours WFO for 44 years

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    +1
    Yes, the drain screw can be reached in place.
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  8. Tinker1980

    Tinker1980 Doesn't ask why, only asks how

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    Finally got my tire fixed, got the battery switched out (Replaced the FACTORY battery from 2001...) drained the crankcase, and since it's a fairly simple job, pulled the flywheel... the seal had moved a little bit but otherwise looked OK, so I used one of my several polaris-specific tools I've made and tapped the seal down onto it's seat. Put it all back together, checked it for fuel, (Slosh... slosh... yup) hit the odd starter switch with the choke on, and it fired up immediately. Leaked a bit of fuel in the join between the head pipe and mid pipe, but none of the gushing from the crankcase. It settled down and idled really nice. It was 1 am, and I backed it out of the shop, turned on the headlight, and hammered it across the pasture. It's the first time I've seen it move under it's own power since my rocket-magician of a son decided that when faced with two trucks, and a 200 foot gap between them, he should get as close as possible to the shiniest truck. It's not as fast as my Raptor, but it's much quieter, easier to ride, and my wife sorely misses riding it. It was running great and all was well with the world, when it ran out of gas and I had to push it about 500 feet back to the shop.

    Thanks, ADVers, for your tips, especially the one about the drain plug.
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  9. concours

    concours WFO for 44 years

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    You're welcome. Stay in touch.:freaky
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