OS 11k carb help

[easy rider]

I got tired of adjusting my stock 3.3 carb. So, I bought an OS 11k carb. It is new and came with the needle settings screwed all the way in. On all three needles. I can make it run. But, I can’t keep it running long enough to tune it. It will not idle at.


To say I’m irritated is an understatement. Why send it like that? There is zero information on the stock settings for this carb that I can find either. Zero. I know the stock settings aren’t meant for the 3.3. But, it’d been nice if the valves weren’t screwed in all the way. I’ve fooled with this so much on the blocks I don’t know which way to even start looking.



I prime it and have to crack the throttle to get it to fire. I can keep it running until I stop giving it fuel. Then it dies. Fires right back up. But, the same thing. I can’t get enough feedback to even know where to begin to set the needles.


Any and all help is appreciated.

 

[tudordewolf]

I got tired of adjusting my stock 3.3 carb. So, I bought an OS 11k carb. It is new and came with the needle settings screwed all the way in. On all three needles. I can make it run. But, I can’t keep it running long enough to tune it. It will not idle at.


To say I’m irritated is an understatement. Why send it like that? There is zero information on the stock settings for this carb that I can find either. Zero. I know the stock settings aren’t meant for the 3.3. But, it’d been nice if the valves weren’t screwed in all the way. I’ve fooled with this so much on the blocks I don’t know which way to even start looking.



I prime it and have to crack the throttle to get it to fire. I can keep it running until I stop giving it fuel. Then it dies. Fires right back up. But, the same thing. I can’t get enough feedback to even know where to begin to set the needles.


Any and all help is appreciated.

Did you buy it new like that? That's odd.

For factory settings, you'll want all the needles "flush" with their housings, that is' not recessed nor sticking out, the face of the screw level with the bezel around it.

For your starting / running issues, it sounds like you need to up the idle screw until it stays running, then you can start to dial in the fuel needles. The only thing to remember is that the idle screw sort of turns "backwards" from the others - clockwise = more idle gap. So you'll want to screw the idle screw in a turn or so, and back the needles out a bit.

 

[easy rider]

Did you buy it new like that? That's odd.

For factory settings, you'll want all the needles "flush" with their housings, that is' not recessed nor sticking out, the face of the screw level with the bezel around it.

For your starting / running issues, it sounds like you need to up the idle screw until it stays running, then you can start to dial in the fuel needles. The only thing to remember is that the idle screw sort of turns "backwards" from the others - clockwise = more idle gap. So you'll want to screw the idle screw in a turn or so, and back the needles out a bit.

Yes. Brand new. Hence my irritation. I don’t know why they’d do that.

Did you buy it new like that? That's odd.

For factory settings, you'll want all the needles "flush" with their housings, that is' not recessed nor sticking out, the face of the screw level with the bezel around it.

For your starting / running issues, it sounds like you need to up the idle screw until it stays running, then you can start to dial in the fuel needles. The only thing to remember is that the idle screw sort of turns "backwards" from the others - clockwise = more idle gap. So you'll want to screw the idle screw in a turn or so, and back the needles out a bit.

No. I adjusted the idling screw all the way “out”. Took the air intake off and checked to see the gap increased when I adjusted it. Still doesn’t help.

 

[NitroR/C]

I got this info: Start with the maximum needle at 2.5 turns from closed, the minimum needle at 3 turns from closed and the medium needle at 1 turn from closed. This should be rich enough to make it run smoothly. Then adjust the maximum needle until you get the maximum speed, then enrich by 1/8 of a turn. Then adjust the minimum needle until you get a good idle and a good acceleration. Finally, adjust the medium needle to get a smooth transition between idle and maximum. You can also consult the manual of the OS 21TM engine that uses the same type of carburetor (11K) for more information on the adjustments.

https://www.os-engines.co.jp/english/line_up/engine/car/manual/21tm.pdf

 

[easy rider]

I got this info: Start with the maximum needle at 2.5 turns from closed, the minimum needle at 3 turns from closed and the medium needle at 1 turn from closed. This should be rich enough to make it run smoothly. Then adjust the maximum needle until you get the maximum speed, then enrich by 1/8 of a turn. Then adjust the minimum needle until you get a good idle and a good acceleration. Finally, adjust the medium needle to get a smooth transition between idle and maximum. You can also consult the manual of the OS 21TM engine that uses the same type of carburetor (11K) for more information on the adjustments.

https://www.os-engines.co.jp/english/line_up/engine/car/manual/21tm.pdf

Thank you.

 

[easy rider]

I appreciate you fellas. I got it running. That info on the link made the difference.

 

[easy rider]

Don’t know if this will be combined into my last post. But, I run the new carb a bit this evening as well. All I can say is Traxxas carbs suck in comparison.

I found another site that tells how to adjust it for TMaxx applications to get a start on the tuning. It died one time throughout the whole tuning process. With Traxxas fuel. Plus, It makes the 3.3 a different animal. It’s so much quicker and over all faster. It’s a great improvement.

For anyone thinking of doing this, the directions on stock settings for a TMaxx says adjust the hsn valve to flush. Adjust the Low speed flush with the steering horn. Which you gotta guess at with the Traxxas carb horn because it’s wider then the one that comes on it and it hangs out past the slide versus flush with it. No worries, it didn’t take much guess work. You’ll have no problems getting it set close enough to start and stay running while tuning. And, to set the middle mixing needle to half a turn from flush with the carb body.

Just Google search OS 11k carburetor settings. And, you’ll find the link to set hours up if it comes like mine did.

The hug is going to be extremely rich. But, it’ll still idle while you run it in. Get the low speed set. Which is so easy. And, leave the mixing needle alone.

Follow the instructions and you’ll be burning fuel instead of tuning.

 

[Chubaka]

Much appreciated. What fuel are you running?

 

[easy rider]

20% top fuel. Not the best but it’s what my local shop has.

I ordered sone master bash for the 2.5 and .15.

 

[EJMOPAR70]

Yes. Brand new. Hence my irritation. I don’t know why they’d do that.

No. I adjusted the idling screw all the way “out”. Took the air intake off and checked to see the gap increased when I adjusted it. Still doesn’t help.

Should be .50mm idle gap for O.S. and the flush the needles