Rebuilding carb... extra part?

[Green P1]

I just got done rebuilding the carb for my HS40 and the kit seems to have come with an extra o-ring. Both needle seats have their supplied ring and copper washer but I've got one more and no idea where it goes. The only place I can think is where I've got the drill bit pointed in the photo. The o-ring is also pictured at the bottom.

help would be greatly appreciated.

 

[metal man]

some of the carbs had 2 o rings on the main jet . i cant tell but if the o ring is more flat then the others it could be for the bowl drain . allot of the older carbs had a drain in them . if you replaced every thing you took out i would not worry at all the kits cover allot of different carbs so there is extra parts

 

[Harleys Papa]

It is the bowl drain if you dont have one just toss it, I thought I missed something too untill I looked at one of my older carbs:thumbsup:

 

[Green P1]

I got it all put back together(new float, needles, ring, seat ect..) and it just DID NOT want to run. I ended up putting the old needles(pictured) back in and its running/idling but not great.

Idle: New then Old

The old one looks identical to the new, just with the tip broken off maybe?

Main: Old then New

The old one looks legitimately shorter, I don't think the tip was broken off this one. Did any of them come short and flattened like this?

Only other thing is I forgot to pull the welsh plug by the idle screw on the side so that didn't get cleaned out. Would that cause much of a problem? Everything has seemed reasonable clean so far.

 

[metal man]

lookin at your jet screws they dont look wright . it looks like the screws that you pulled are out of a like a 8 hp carb . i have a hs 40 and that has the long pointed screws . the snowblower i just did a carb kit in a hmsk 80 had the cut off ones like your showing and that is a 8 hp. is it possible that you have the wrong carb on your motor? i know that the one on the blower and my mini motor look like they would fit each other . how did the motor run before you did the rebuild ? did it run ok or was it bad ?

 

[Green P1]

It'd been sitting for about 14 years so it ran kinda rough... but I seem to remember it running great as a kid. Always kinda hard to start, but still great.

She's also smoking like a sob these days. Guess a fresh set of rings is next on my list of parts to order.

Would the lack of compression due to the out rings make is seem as if the carb was badly out of tune?

 

[The Restore Kid]

Actually I'm with Metal Man and say the kit was for an 8 horse, or maybe even 6... But the short stuby one for the bottom, (main jet) should have more of a point for the smaller hole in the 3 or 4 horse sized carbs..... And Your idle screw should be thin and pretty long to reach way up in there...

It almost looks as if the first pic is actually two idle screws....

I probably have a couple used screws that will work good for ya.. Sounds to me like you can't really MAKE any adjustments because the screws aren't fitting right and not penetrating up into the jet like it should..

 

[metal man]

you may need rings , i would see if it will run and clear out of it . one cheap way to check your compression is . take the recoil shroud off so you can grab the flywheel . with the plug in the cylinder . make sure the kill is on and the plug wire is grounded to the body/block you dont want to start the motor .now rotate the flywheel till you feel it hitting compression give it a quick jerk , if the flywheel rebounds sharply its good if not well time for rings or a valve job

 

[Green P1]

I may very well have the wrong needles/carb for my hs40, but it did run fine back in the day so I'm inclined to believe it still could/should.

Finally got a day off so I'm gonna fart around with the carb some more and try to get it running better. Change the oil, the spark plug ect... Any other routine maintenance I should consider as I try to freshen up this old engine?

I consider myself pretty damn good mechanic/Mr Fixit, but I know next to nothing about small engine work.

 

[Green P1]

Today I changed the oil, bought a new(correct) spark plug, set the rebuilt carb with old oddball needles to the recommended presets and....... it fired up on 3rd pull!!! That's something this bike has never done in the almost 20 years I've owned it. After fiddling with the carb for 5 minutes I think I've got it about as close to tuned as I'm gonna get it.

Cruised around the neighborhood for about an hour(got her up to 35mph on a slight downhill.)

She's still blowing white smoke like a sob, but she's finally a runner.

I've got a video of the hs40 idling that I want to put up here if I can figure out how, to see if y'all think its idling to fast and show how bad the smoke is.

 

[The Restore Kid]

most people use youtube to store the video, then link it here..

 

[Green P1]

I know the video kinda sucks, its the first time I've ever loaded one from the Blackberry to the computer... not impressed.

[YOUTUBE]<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/Lhb_l5F3UZw&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/Lhb_l5F3UZw&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>[/YOUTUBE]

 

[Green P1]

Filled the tank up with gas and took her on a nice 5 mile ride without incident. She's running like a top, albeit a top that is followed by thick cloud of smoke...

The rings have already been ordered, but what else should I go ahead and replace while I have the HS40 torn down? I'm thinking crankcase and head gaskets for sure. Any other suggestions?

 

[Green P1]

bump for an answer

 

[The Restore Kid]

If the valves are and seats are OK I'd say leave them.. Although if there is an abundance of slop in the valve guide you may want to ram some brass guides in her.. :hammer: If the cylinder is honed, rings are right fit and installed correctly you're probably good... Although if the valve guides are real bad it will still smoke a little.. Nothing like a burnt up cylinder though... a Smokey HS40 is not uncommon as they are fast running engines and usually lead a hard life...