Big Red 250 refuses to live

[UncleBubbles]

Went to fire up my 250 after sitting all winter, went through all the checks, oil, gas cables, ect. My electric start isn't working at the moment because I think my neutral switch is finished, so I was kicking starting it. Brought it around slowly till it hit compression, and went for it, it fired once (I was amazed at that) then died. So I was slowly kicking it looking for compression again but it seems to have disappeared, it just keeps rolling over and over and over. Wondering what could have happened in there, sticking valve maybe? I don't think it blew any gaskets and the kick start clutch is definitely working because I can hear the engine itself turning. I'm completely stumped as to what could have happened that one time it fired. I do have a complete other 250 engine that I can peel parts off of.

Side note: Where would one find the neutral switch on these engines? Please don't tell me I have to split the cases...

Thanks guys.

[jakerman]

maybe the valve is stuck open? Doesit have any compression at when you take the plug out and feel for air when you kick it over?
Or even better a compression gauge to measure the psi. idk just trying

[atc007]

N switch is behind a little black tin cover behind the right foot peg,along side the R switch. Usually the wires just need cleaned,and re"pinched" to stay on there tighter. It is the green wire. And yes,a compression test is necessary.

[UncleBubbles]

I'll compression check it tomorrow, was running great when it was parked for the winter. Aside from the stated I am at a complete loss.

[matt86200x]

I live in winnipeg if you need a hand. Your problem sounds like it maybe the oneway clutch i had that happen to me a few times

[UncleBubbles]

It stuck a valve. I popped the adjustment covers off the head and turned it over by hand, and the exhaust valve was not returning all the way. So off came the entire cover to try and figure out why it all of the sudden is doing this, and with a gentle tap of a screw driver handle it will come back up all the way. Think it's just a lack of lube in there from sitting all winter? I can't compression check it because I don't have the right end to fit the hole. Thanks for the help guys.

[250esbigredNY]

sounds like a CARB cleaning first thing on your list and drain old gas tank out first then put fresh gas in and fresh spark plug then start it up. Most bikes has been sitting all winter or at least a year, 1st thing on list is clean carb and fresh gas then do tune up too as well.

[250Eddie]

Try this take a thick cable 8gauge amp wire and ground your battery and touch the positive to your starter nut to see if the starter aint stuck like mine was that will also help test the compression on the engine w/o kicking your leg off.

[4cylinders]

hey, too late, but marvel mystery oil works great.

[UncleBubbles]

Not trying to insult anyone, but you guys seem to be missing the point, I'm trying to get my compression back. I'm not worried about my electric start at the moment or how clean my carb is. Neither of those two things make a single difference if the trike is clearly not going to run because of a loss of compression! Ok rant over, if anyone has any tips on the valve I'd like to hear them.

[xlover]

i would get somting to stick on the end of the valve and tap it lightly maybe some lub

[haywiremechanic]

From what the original poster has described, the exhaust valve is sticking in the guide. You can try some penetrating oil applied to the valve stem from above, and sprayed in through the exhaust port. The sure fix is to remove the cylinder head, disassemble it, and clean the rust from the valve stem and guide.

[atc007]

I would pull the head and do a correct valve job. Done once,done right. I have actually never seen this on a atv or bike! Did it smoke a little before? Must have some oily residue to have hung a valve. While your in there ,I'd pop the cylinder off,hone it and ring it. New engine!

[UncleBubbles]

It lives on! I let the valve soak on penetrating oil over night and got it moving freely again. Slapped the cover back on and did the clearance on the valves. Intake came out to a perfect .003 and the exhaust was somewhere around .009 when I gave up trying to find out exactly where it was, brought it down to .003 as the manual says. 7 more kicks and it fired up and sat there idling. I know I should go through the entire top end but in the fall it's going to be completely torn down to the frame including splitting the cases to be rebuilt, so I figure it can go one more summer on the original top end. Now onto my electrical gremlins!!!! fun fun!!

[4cylinders]

hey, marvel will clean up the valve stems and free up the rings.
run it for a while, then change the oil and filter.