Carb issues
- Thread starter Five603
- Start date
mckutzy
Well-known member
Dude...
Whats the engine it is for?...
Whats the engine it is for?...
Brianator
Gettin' er done!
And what carb for that matter?
We can't make bricks without clay... help us out here! Lol
It’s a 150cc gy6 in a Kasea LM150llR. I just replaced it with a stock carb.
Sorry it was kind of a general question. I know the EPA has some of the carbs set and block access for adjusting the jets. They have a tendency to run lean and after the engine gets a little age on it it needs to be adjusted richer. This is common on mowers and similar equipment.
I wondered if it was an issue run into on the gy6 motors.
Sorry it was kind of a general question. I know the EPA has some of the carbs set and block access for adjusting the jets. They have a tendency to run lean and after the engine gets a little age on it it needs to be adjusted richer. This is common on mowers and similar equipment.
I wondered if it was an issue run into on the gy6 motors.
Brianator
Gettin' er done!
Round slide style carb? What clip is the needle set in currently? Start with the mixture screw out 1.5 turns from lightly seated. Stock replacement carbs can be sold for 50cc and up by sellers and although they CAN work out of the box they generally need to be rejetted and set up for each individual motor. Do you still have the original carb and did you have the same issue with it? Any upgrades done to the motor?
Karttekk
Well-known member
Try raising the float in addition to the other suggestions.
Brianator
Gettin' er done!
Not trying to undermine you but I only see that working if the engine was starving for fuel during high demand and drinking the bowl dry...
Here's a post I wrote awhile ago to help a guy with a Mikuni flat slide carb, same applies to yours if it's a slide carb with a midrange needle jet/jet needle, keep in mind you want to start with the pilot circuit, then the mid range (needle) and then main jet:
I'd start with the needle in the middle position if it has 5 slots or as it came if only 4 slots. Dropping the needle by raising the clip leans it out while raising the needle enrichens it. Start with the mixture screw at 1.5 turns out from lightly seated, being an "air screw" (because it's on the intake side of the carb) by screwing it in you're enriching the mixture and screwing it out leans the mixture.
The goal is to size the pilot jet so the mixture screw's ideal setting is between 3/4 & 2-1/4 turns, if it's not you need to resize the pilot jet. Less than 3/4 needs a larger jet while more than 2/1-4 needs a smaller pilot jet (the opposite jetting applies to carbs with a fuel screw - motor side of carb - but the procedure stays the same). Best way I've found to set it is to increase the idle, play with the mixture screw until you have achieved the highest and smoothest idle then bring the idle back down to ideal. If off idle acceleration isn't crisp, play with the mixture screw a little and see if it cleans up. The pilot circuit is most effective from off idle to about 1/4 throttle then the needle comes into play, all circuits must be tuned individually using their effective throttle positions and sometimes then fine tuned to work together. When adjusting the mixture screw always allow up to 30 seconds for the new setting to take effect and always make smaller adjustments, if looking at it like a clock then 1 to 2 hour adjustments are good.
Karttekk
Well-known member
Symptoms of Incorrect Float Heights: If the fuel height is too low, the engine will display a lean running condition, where the engine typically hesitates before accelerating or surges as the throttle is opened.
JTSpeedDemon
2019 Build Off Winner!
Howabout a vacuum leak check?? Fresh gaskets on the intake and carb, cracked intake? Everything torqued to spec?
Brianator
Gettin' er done!
Yup, IF he's displaying those symptoms which he didn't mention so I didn't feel suspect of. Good advice though!
More good advice!
Karttekk
Well-known member
The last GY6 carb I had trouble with was due to the O-ring under the intake manifold. They get compressed over time or crack and suck air as JT has mentioned. Replace the insulator gasket and O-ring, check the intake for cracks while it's apart. Make sure your fuel valve or petcock is allowing good fuel flow.
Attachments
-
carb_parts.jpg
Brianator
Gettin' er done!
same difference for all intents and purposes.
Brianator
Gettin' er done!
Not sure, I gave instructions on how to figure that out above. Unless you mean the physical size of the jet in which case you'll need to pull it to compare, I cant tell what model that carb is a copy of and the part number is no help unfortunately...
The spring on your idle adjustment looks almost maxed out, that could be an issue in itself. If the throttle is opened too far there's not enough vacuum to draw fuel from the bowl when it's closed at cranking speeds. About a 1mm gap is an ideal starting point.
How about another couple pics of the carb so we can more, including the air mixture screw.
The spring on your idle adjustment looks almost maxed out, that could be an issue in itself. If the throttle is opened too far there's not enough vacuum to draw fuel from the bowl when it's closed at cranking speeds. About a 1mm gap is an ideal starting point.
How about another couple pics of the carb so we can more, including the air mixture screw.
I have the idle adjustment maxed out to get an rpm rate where it won’t die. I think it was at about 2300 rpms.
I’ll send more pics. I’m concerned about the physical diameter. I assume they are about the same for the gy6 carbs. Looking at the ones available online it appears there are some size differences.
I figured I would buy a set but this question arose.
---------- Post added at 02:48 PM ---------- Previous post was at 02:46 PM ----------
I’ve eliminated everything but the float and if that isn’t out of tolerance I may have to reject. Y’alls instructions have been very helpful.
I’ll send more pics. I’m concerned about the physical diameter. I assume they are about the same for the gy6 carbs. Looking at the ones available online it appears there are some size differences.
I figured I would buy a set but this question arose.
---------- Post added at 02:48 PM ---------- Previous post was at 02:46 PM ----------
I’ve eliminated everything but the float and if that isn’t out of tolerance I may have to reject. Y’alls instructions have been very helpful.
Karttekk
Well-known member
Going with another hobby may end up being the best solution.