Small 2 cycle engine --- repairs---

[muddog]

Anyone out there, that has ANY ideas/ tips on Getting a small piston unstuck,

Sadly its in the VERY LOWEST part of the stroke....

So My old trick of just taking a rubber mallet, and tapping on it till it moves, isn't viable...

So Who thinks I'm gonna be taking the WHOLE DAMN THING apart.... ?.?

And please If you can think of any ways to pull/ grab / break that piston out speak up.... ( I got cookies)

[dexter]

one question: what is the 2-cycle motor attached to?

[Lonesome]

Fill the cylinder with diesel fuel or PBblaster(spray penetrant) and let sit, will free right up and maybe even fire!

[dexter]

wow that's one i have not heard of before. Sounds like it would do the job.

You could always apply heat to the cylinder walls to expand it and try to knock it free with a hammer while the cylinder is almost red hot. It should expand the cylinder enough to let the piston slip free. I might run, but if it had locked up then you will need new rings and get the cylinder refinished to get rid of the edge left from the rings locking to the walls of the chamber.

[Lonesome]

If anyone needs anything on engines give me a holler i do alot of work on performance ATV and do tons of Automotive and Diesel stuff!

[muddog]

http://www.mopedarmy.com/photos/brand/85/1690/

^ thats about what it looks like, heh VERY "Raise against " ( you know that music video)

Anyway its my buddy's I ended up letting it sit pretty much full of marvel mystery oil, so Today I pulled the top-end off of it, gave it some taps with a mallet, guess what ?.? IT moved, like a tiny bit so I was like hell maybe it isn't stuck, I cleaned the top-end, put it back on, and I turned to the place I didn't want to crack open, the case.

*edit* Also lol, it was like 32 degrees out when I played with it so perhaps with the metal cold it had contracted just a tad ?.? *edit*

I opened it up, to find there wasn't nearly any GEAR OIL in it. (AGH )
I played with the clutch some, didn't really do shit to it, put it back together.
Filled it with oil and tried pedaling it some and pulling in the lil starter lever, and just my dumb luck it turns over....

Very nice, now just to get all the damn rust outta the old metal gastank, throw some new tubes in the tires, and we be all set to start heading to work on it, thus saving a nice bit on gas. :-P

[Lonesome]

Throw some gas in your tank and a handfull of nuts, bolts, nails... whatever you got laying around and shake it till your arms hurt so bad they feel like there going to fall off. Empty gas and nuts,bolts, nails and rinse with fresh new fuel.

after putting it all together its a good idea to put an inline fuel filter in the line to the carb so you dont get rust in the needle and seat making fuel pour out of your carb!

PS... love msi!

[muddog]

Aye, It lucky had a fuel filter so pretty much it clogged and coked it out , I'm guessing that's why the person sold it... so yeah we have replaced all the fuel lines but won't have off from work till monday so no time to work till then, should have it up and running by then :D

[Lonesome]

Hopefully all goes well for you

[muddog]

Well we got spark...and it seems the carb is flooding our poor lil motor with gas, I really wish it was a kickstarter, not this silly pedal start... Looking into buying a new carb for it now...

[Lonesome]

Did you try cleaning the old one first? allso measure the old one and let me know how big it is i have a couple laying around from my past rebuilds

*edit* you can allso check the float level. If you dont know how let me know and ill learn you :-p

[muddog]

Aye we took the whole sucker apart cleaned it with a toothbrush, the float is sooo funky, it has like no adjestment.. I think its a 16mm, its pretty small.

[Lonesome]

If you can, find a rebuild kit for it. the needle probably just isnt seating correctly and is not shutting off fuel flow. that... or your float is shot. Set the float in a cup of water and see if it sinks or floats. Float should float if that wasnt obvious enough :-p

[muddog]

Yeah I was thinking our float might be awful sink .... x . x

Just gonna play with it sum, I tryed starting it on WD40, and it wasn't even poping or back firing..sooo I'm pretty well ready to blow the few bucks on a **pro** to look at it for me,

[dexter]

well a lot of bikes like yours use a magneto for the spark. If that is dead or the magnetic ring is not aligned it will cause that problem. Did you take the spark plug out and place it against the side of the block and try and crank it over to see if it got spark?

[muddog]

Aye, we looked into that, and yes there is spark but its not as bright. as most other motors Ive worked on, I might try buying a new plug as it would be cheap and easy

[Lonesome]

a manual wouldnt hurt either... they are quiet cheap as well! Free even if you look hard enough. Sounds like you need to look into timing and float issues. If you put your thumb over the plug hole will it pop your thumb out of the hole while you roll the engine over?

[muddog]

Aye compression seems spot on, but I fear the exhast pipe ( A hacksaw custom job) isn't giving the two cycle any back preasure, But I have seen it running with that pipe so I dunno.

[Lonesome]

2 stroke pipes and 2 stroke reed valves are about the best thing besides porting and polishing you can do to improve on them. I would love to get my hands on this thing now...

[muddog]

I honestly don't think it has a reed in it, But yeah I love my two cycle engines ^.^

[Lonesome]

Man, gotta be some old school two stroke not to have reeds... early 70's jsut started using reeds on stuff. I should toss some pics up of my 250R motor sometime for fun... we will see

[Lonesome]

http://i613.photobucket.com/albums/tt219/Lonethehusky/S5030435.jpg
http://i613.photobucket.com/albums/tt219/Lonethehusky/S5030439.jpg

For fun :-)

[muddog]

Ah the 250R, your talking about the lil racing quad right ?, Gah I got a Yamaha Blaster that friggen keeps up with my lil 85 dirtbike no problem.. I swear two strokes just somthing about that crazy lil power band of them Just keeps me hooked :D

[Lonesome]

That ones actually an 83 3 wheeler! 85 and later were all liquid cooled. The 81-84 250R were more of a woods machine. More torque to them. The 85 and up were made more for racing and motorcross. I ported and pollished that cylinder but you cant really tell by the pictures. Right now its geared for ice racing (coming up soon) which will be an absolute riot!

[muddog]

Ah 3 wheelers the redneck's way of saying " Screw physics" I got a lil Yamaha 75cc 3wheeler thats been sitting in my barn for the past 10 years...I really should get that lil beast up and running some time...

[Lonesome]

I rather enjoy my ATV's there amazingly fun and dont cost all that much to run! anyway back on topic... you get that moped running?

[muddog]

Ah, yes the moped isn't going yet... Its pretty well on the back burner for a few weeks I think