3W 50i help please

[sweetpea]

Alright......I am trying to get this 3W 50i running for a good friend.

This is what I got.

Its a rear carb, so that always makes it fun and easy to adjust.

I started here

H -1
L -1.5

The motor will start, but idle high. Transition is pretty good to full and runs fine at full throttle.
Go back to idle and its still high. If I try to adjust to lower idle it will hesitate to get there and when it does it dies. Start it right back up and it will again go to a high idle then back itself down to low idle and die. If you get it started with the lower idle set as described and get the motor running at about half throttle then back it down to idle.....it does the same....stays at a higher idle than works it way down to the low idle setting and dies. I've adjusted the travel and subtrim about 100 times trying to find the sweet spot ......out of my 3 other 3W's I've never had to work this hard to get a low idle...so help if you can

Things I've tried

--H needle from .5 -2
--L needle from 1-3
--all sorts of configurations with needle settings
--motor had the black carb funnel plate....took it off .....no difference
--took the carb off and the inside looked clean. (wiped it off just to be sure)
--reeds appeared be ok and not stuck
--doesn't appear to be any leaks in the gas lines
--....I also tried moving the butterfly plate 180 on the throttle.....no change (see below as to why I did that)

One thing I noticed that is different from my 106......the choke butterfly has a small half circle cut in the edge. The throttle butterfly has the same half circle (but smaller) in it. On the 50 motor the choke has the butterfly half circle cut but the throttle plate is a complete flat circle, without the cut in it. So I tried making the throttle butterfly look just like my 106 as far as where the screw head was and the angle, since I didn't have the small hole in it to line up

Anyone have a 3W50 out there that can confirm this is right?

[flyin woodbutcher]

you have a air leak some where . Probably the reed block. I had one of these a few years ago. Sent to AI a few time for the fix.

[sweetpea]

is the butterfly correct?

[Dennis C]

I kind of had the same problem with my 3w 80..come to find out when i put the arm for the throttle i had the butterfly backwards.

[sweetpea]

I already put the butterfly 180 to its original config..........that did not make a change.

[Cookie]

Hi Sweetpea (boy that is a worry saying that to a bloke) LOL, I have a 3W80 xi that I am having the exact same problem with. The local 3W agent is attempting to get me another carbie to try but I am at this time unsure what the problem is. I found that mine had a reed that was intermittently sticking open with a sliver of rubber from the reed carrier. I also noticed a leak from the reed box at the point where the crankcase joins, there was a step at the point they joined. I machined it to give a flat surface and have reassembled. I will be testing it on Monday (Ausy time), if it works I will let you know. If you find anything in the meantime can you shoot me a pm.

Good luck.

	Quote: Originally Posted by sweetpea
	Alright......I am trying to get this 3W 50i running for a good friend. This is what I got. Its a rear carb, so that always makes it fun and easy to adjust. I started here H -1 L -1.5 The motor will start, but idle high. Transition is pretty good to full and runs fine at full throttle. Go back to idle and its still high. If I try to adjust to lower idle it will hesitate to get there and when it does it dies. Start it right back up and it will again go to a high idle then back itself down to low idle and die. If you get it started with the lower idle set as described and get the motor running at about half throttle then back it down to idle.....it does the same....stays at a higher idle than works it way down to the low idle setting and dies. I've adjusted the travel and subtrim about 100 times trying to find the sweet spot ......out of my 3 other 3W's I've never had to work this hard to get a low idle...so help if you can Things I've tried --H needle from .5 -2 --L needle from 1-3 --all sorts of configurations with needle settings --motor had the black carb funnel plate....took it off .....no difference --took the carb off and the inside looked clean. (wiped it off just to be sure) --reeds appeared be ok and not stuck --doesn't appear to be any leaks in the gas lines --....I also tried moving the butterfly plate 180 on the throttle.....no change (see below as to why I did that) One thing I noticed that is different from my 106......the choke butterfly has a small half circle cut in the edge. The throttle butterfly has the same half circle (but smaller) in it. On the 50 motor the choke has the butterfly half circle cut but the throttle plate is a complete flat circle, without the cut in it. So I tried making the throttle butterfly look just like my 106 as far as where the screw head was and the angle, since I didn't have the small hole in it to line up Anyone have a 3W50 out there that can confirm this is right?