Running issues

[mortimer]

Ok, here's my scenerio. I think I fixed the overflowing carb issue I had before.
Float adjustment. I got it back together and this would be the second try after rebuild. At first it seemed like it was overflowing gas again. Started to leak. I immediately unhooked the hose to the impulse line at the fuel pump. Tried to start it with the gas left in the carb. And after a little bit of choking, she started. And would die at about 1/2 to 3/4 throttle. After it stalled... nothing. So I tried the same thing again. Let the carb get some gas, unhook that impulse line again. Ran it for a minute at about 1/4 throttle and she died as I gave it more. I did the same thing once more, although when she started running I attempted to hook the impulse line up while it was running. Watching for any leakage and none. I then kept her running with the choke and throttle and adjusted the pilot screw. Seems to run the best when it's almost 3 turns out and sputters when it gets farther out. Now warm, it would start easily with just a tap on the choke. Issue here is very slow throttle responce and dying about 50% of the time when I give it full throttle. I was feathering the gas pedal when she starts to die to keep it going. And avoiding it getting too high in RPMs. She's firing right up with a tap on the choke though. That pilot screw is pretty loose because it is so far out. And while pulling the impulse line it would release a puff of air like a coke bottle. Seems like that's quite a bit of pressure. I have gone over it for over any air leaks. There is a small hole in the plastic hose from the air cleaner to it's expansion chamber. I am contemplating on how to fix that without using an ugly peice of tape on the outside. That would probably come right off after getting dirty. Although after it was warm, the choke worked pretty good to get it started. And that hose is just stuck on there now with no clamps. Not sure if that means anything. It did start to leak a tiny bit of fuel at what appears to be the hose fitting that goes into the carb. Nothing at all when she was running. Haven't tried to start it after it has cooled. In fact it's probably still hot as I write this. And I smell like exhaust right now. Oh yeah, It has good spark also, if that helps. Any suggestions would be greatly appreciated.

[patmcfann]

did you dip the carb and take sometorch tip cleaners to make sure ther is no blockage of the jets? also ive found that if there is a gas leak while not running there is an air leak while running.good luck sometimes carbs are not fixable

[DOOmsman]

The pilot screw out three turns and loose seems to point that way. like pat said I would look very hard at the piolt jet and passages.Get a set of tip cleaners

[invalidsession]

What they said ^^^^^^ up there. You have the classic symptoms of a partially clogged main jet which = not enough fuel and too much air, hence the need for choke to equalise the fuel / air ratio. The nasty freaking fuel that the EPA wallahs force us to buy these days will varnish up your jets faster than a three bit whore giving you a dose of the std's. My son has a Yamaha dirt bike that was running great just three months ago, the sucker needs full choke to even get it to fire much less run, Ditto my chain saws, weed wacker etc.
Unless you have have some additional carb issues (worn butterfly etc) this is your most likely issue. You should also take care of that air box leak, CC's are notoriously sensitive to any leaks anywhere in the system.

Chris.

[mortimer]

Have never had to clean those in any dirtbike or small engine carb before. So i am doing research on what the best way is. I did soak this carb in cleaner and blew out the holes with air. This is usually the farthest I have had to go in cleaning a carb other than the needle/seat. I am just an at home mechanic. Have rebuilt engines but never a carb. So bear with my lack of intelligence in the carb department. #1 is the pilot jet and #6 the main. They appear to be just a brass screw with a hole by the looks of the 2nd carb I have. Haven't taken those out of either. Not exactly sure what is above 6 in the picture. I'd imagine removing and cleaning all 3. After doing research on the net I see some people using guitar strings and carb cleaner to help clean those out. I have a plethora of strings around here. I guess it's nice also to have a 2nd carb to dismantle. Gonna start with the dry one first to see what I am getting into. That one obviously had water in it and the alluminum is corroded something fierce. Looked like gravel in the bowl when I took it apart. Wish me luck.

And thanks a ton for the advise. Will update my success. Or lack there of.

[invalidsession]

Originally Posted by mortimer

Have never had to clean those in any dirtbike or small engine carb before. So i am doing research on what the best way is. I did soak this carb in cleaner and blew out the holes with air. This is usually the farthest I have had to go in cleaning a carb other than the needle/seat. I am just an at home mechanic. Have rebuilt engines but never a carb. So bear with my lack of intelligence in the carb department. #1 is the pilot jet and #6 the main. They appear to be just a brass screw with a hole by the looks of the 2nd carb I have. Haven't taken those out of either. Not exactly sure what is above 6 in the picture. I'd imagine removing and cleaning all 3. After doing research on the net I see some people using guitar strings and carb cleaner to help clean those out. I have a plethora of strings around here. I guess it's nice also to have a 2nd carb to dismantle. Gonna start with the dry one first to see what I am getting into. That one obviously had water in it and the alluminum is corroded something fierce. Looked like gravel in the bowl when I took it apart. Wish me luck.

And thanks a ton for the advise. Will update my success. Or lack there of.

The varnish build up in the jets is very hard to see, you can soak and soak and blow all the air you want through them and they will look PERFECT but the varnish may still be there hence the use of the tip cleaners etc. Just be very careful not scratch or enlarge the holes.

Chris.

[mortimer]

Any suggestions on how to get these brass pieces apart?
I have them out of the unused carb and the 2 above #6 in the pic are tight. Do not want to screw them up if possible.

[invalidsession]

Soak them in PB blaster or similar for a couple of hours and use a screwdriver that is very snug in the slots to avoid damaging them. A little heat may also help to "crack" the varnish that is likely acting as thread locker.

Chris.

[mortimer]

Well, I have soaked these in pb blaster and boiled with no results. Still locked together. Don't want to smash the brass when holding it while trying to get them loose. The main hole looks good, got some dirt out of it, but the tiny ones on the side, I cannot get anything through due to the piece inside it. They "look" clean but who knows. Guess I am going to have to get at the other carb. At least I know what I'm looking at.

I have read a few articles on running bikes on carb cleaner alone. Then letting it sit. I believe they said Seafoam or Berrymans Chemtool. Gunk Hydra-Seal was the 3rd but cannot find it around here. Think this may help if all else fails?

[Jimmie]

Berrymans Chemtool B12 works for me.