Stalling when it should be running By 260orbust (Read 742 times)

[260orbust]

Its a linhai 250 engine that's had problem after problem.

This part happened last year.
Put a new carb on checked over everything (valves, idle, etc) hop on and ride 50 miles on the freeway no problems and get off, STALL! Had to get towed home.

Today
Getting it ready for either sale or renting out at the dmv. I put on a new coil, jump the battery and it starts. Problem is it keeps STALLING every time I give it some gas. There's also some backfiring. I turned the screw on the carb all the way in and then out 1 1/2 turns, same results.

I'll put some video up in a few minutes

www.youtube.com/watch_popup?v=FuZn_uXQ0hs&vq=medium#t=19

www.youtube.com/watch_popup?v=BhgwDN-N53o&vq=medium

[Alleyoop]

Richen it up, start it like you did and turn the fuel ratio screw COUNTER CLOCKWISE 1/4 turn at a time and Watch your TACH. If the RPMS go up repeat the 1/4 turns until nothing happens or the RPMS drop then TURN it CLOCKWISE 1/8 of a turn. Give that a shot.

Now if your rpms do NOT GO UP turning it COUNTER CLOCKWISE then go CLOCKWISE same procedure but the Opposite turning the Fuel Ratio screw.

After EACH 1/4 turns wait about 10 seconds or so to allow the motor to catch up with the new setting.
Alleyoop

[260orbust]

OK I'll give a shot.

[Alleyoop]

It is just a fuel delivery problem so we will get it.
Alleyoop

[260orbust]

Done and working!

Thank you very much! ;D


There is still some backfiring but it's running. I tried to get the idle at 1700 but every time I'd get it there, I'd gun the throttle a tad and it would stay at 2500, then rise to 3000 and stay there. So it seems happy at 1500. Surprisingly the fan that I thought had given up the ghost started working again!!

Now the last part is how can I determine if it is "truly" fixed? Last time I thought it was and ended up stranded 50 miles from home, so there is no way I'm going any where on it.

[Alleyoop]

Ok, backfireing is caused by a LEAN condition, How many turns is the Fuel Ratio Screw out from the closed position do you know. Sounds like you may have some AIR LEAKS, make sure the clamps holding the carb are nice and tight as well as the Air Filter side and there are no open holes in your Air Box or RIPS in the Tubeing going to the air box and carb or maybe a hose came off the air box and is sucking in to much air.

When you give the throttle a quick twist does it should Rev up right away and come down back to idle or does it hang on high rpms then drop? It should go VROOOOOOm and Back down to Idle with a twist of the throttle.
Alleyoop

[260orbust]

Oh lordy I didn't count but at least 2 1/4; I think I did hear some hissing but not really sure. I'll get at it again in the morning.

When I set it at 1700 the rpm's would not come down, infact it would rise but when I set it to 1500 it would come down. Cannot remember if it was fast or slowly; I'll check tomorrow.

[Alleyoop]

Get a Spray bottle of anykind and fill it with water. Then Spray INDIVIDUAL areas, By the INTAKE, by the Clamps where it holds onto the carb on BOTH sides and check the tubeing from the Air box for cracks etc.. WHEN SPRAYING and the IDLE CHANGES you found a LEAK.

If the RPMS do not come down and NOT LEAKS turn the Fuel Ratio Screw Counter Clockwise to Richen it up. Give it another 1/2 turn Counter Clockwise. You DO THIS AFTER THE MOTOR IS WARM at LEAST let it IDLE FOR 5 MINUTES so the ENRICHER cuts off the EXTRA FUEL.
Alleyoop

[260orbust]

Yep! The intake has a leak where it connects to the box. I had to modify it to get it to stay on so now I'm gonna take it off and use some rtv gasket maker on it. Took it for a ride short ride around and OMG it feels so unstable compared to my busa. Did get it up to 70 mph on the Speedo with no problems. I noticed when I slowed down that the rpm needle went up to about 10, actual engine speed did not though. Might be because the battery is shot.

[Alleyoop]

GREAT!! Good job, now at least the suckers rock and rolls
Alleyoop