Traxxas Jato carb

[HDRIDER56]

So I just went through my second carb body on Mt Jato, 1st one was cracked whe. I got the car, I don't have any actual road miles on the new one yet, I've been fighting it not idling, found the idle screw hole is stripped out. I see there's two aftermarket that are talked about the most. The OS 11k/ or the Losi 3.4. Any suggestions would be greatly appreciated

 

[Chubaka]

O.s. is readily available. The 3.4 is long discontinued and dried up.

 

[Weezel]

You shouldn't have any issues with the metal OS 11K carb getting damaged like you're experiencing. The 11K carb at least for my experience holds a tune better. I found them to not be as finicky when minor needle adjusting was needed.

Like @Chubaka mentioned the Losi Carb is a rarity if found. Just be aware that they are a plastic bodied carb like the stock Traxxas carb.

Don't get the OS 11KR carb as it's equipped with the Traxxas Revo style throttle arm, not a ball end style like needed.

 

[HDRIDER56]

O.s. is readily available. The 3.4 is long discontinued and dried up.

This is why I posted the question, I wasn't finding any current posts about carbs upgrades.
YouTube had a video about a 3.5 carb upgrade, I didn't see who made it, said it was a good one also. Is the O.S. a good drop in replacement?

 

[tudordewolf]

This is why I posted the question, I wasn't finding any current posts about carbs upgrades.
YouTube had a video about a 3.5 carb upgrade, I didn't see who made it, said it was a good one also. Is the O.S. a good drop in replacement?

Fantastic, I put it on my TRX-swapped MT and also put in a ceramic rear bearing, it idles super stable and runs better than it did with the stock carb - cooler, more powerful, and more responsive:

 

[HDRIDER56]

Fantastic, I put it on my TRX-swapped MT and also put in a ceramic rear bearing, it idles super stable and runs better than it did with the stock carb - cooler, more powerful, and more responsive:

I got a question, I see you're only getting smoke out of the exhaust when you hit the throttle. My Jato has smoke just pouring out all the time, the carb is currently set to the factory settings (or at least it was) I wad trying to lean it out when I found the stripped idle screw. After backing down on it the HSN it wouldn't stay running, I couldn't get the 1mm opening set. Was I going in the right direction? I have no idea when the last time this rc was actually ran before I got it, I've had it outside a few times for a few quick runs, nothing for any length of time. These small little issues are killing me. Lol
I need to get the original radio system, I believe I need that stability setup to help keep it on the road. I hit everything but the street. Lol newbie here

 

[tudordewolf]

I got a question, I see you're only getting smoke out of the exhaust when you hit the throttle. My Jato has smoke just pouring out all the time, the carb is currently set to the factory settings (or at least it was) I wad trying to lean it out when I found the stripped idle screw. After backing down on it the HSN it wouldn't stay running, I couldn't get the 1mm opening set. Was I going in the right direction? I have no idea when the last time this rc was actually ran before I got it, I've had it outside a few times for a few quick runs, nothing for any length of time. These small little issues are killing me. Lol
I need to get the original radio system, I believe I need that stability setup to help keep it on the road. I hit everything but the street. Lol newbie here

I've got the 11k carb on it because I was having some of the same problems tuning it with the stock carb. I barely had to adjust the OS carb. It started on factory settings, idled under 200°F, and then I only had to slightly lean both needles to get it in the sweet spot + a little rich.

If you've got smoke coming out pretty steadily at idle, it sounds like the low speed is a bit too rich & the idle a little too high. There should always be a little smoke visible, but it should only be thick "clouds" when you hit full throttle. If it's already puttering out smoke & very laggy when you hit the throttle, the low speed needle might be too rich.

All these issues may have you going in circles if the stock carb just isn't going to perform at the same level. I think it's not just about high/low/idle needle settings, but the carb's ability to deliver a consistent fuel air mixture at low throttle settings.

Imagine a can of spray paint. Even the cheap brands will work pretty well when you press the button all the way down, but will start to sputter and produce a blobby result if you only hold the button down halfway. The OS carb is like an airbrush that can produce a fine, smooth spray all the way down to its lowest flow rates, so you can achieve an idle that just isn't available on the stock carb

Edit: here's mine installed, I think it looks like it was always meant to be:

 

[HDRIDER56]

I've got the 11k carb on it because I was having some of the same problems tuning it with the stock carb. I barely had to adjust the OS carb. It started on factory settings, idled under 200°F, and then I only had to slightly lean both needles to get it in the sweet spot + a little rich.

If you've got smoke coming out pretty steadily at idle, it sounds like the low speed is a bit too rich & the idle a little too high. There should always be a little smoke visible, but it should only be thick "clouds" when you hit full throttle. If it's already puttering out smoke & very laggy when you hit the throttle, the low speed needle might be too rich.

All these issues may have you going in circles if the stock carb just isn't going to perform at the same level. I think it's not just about high/low/idle needle settings, but the carb's ability to deliver a consistent fuel sir mixture at low throttle settings.

Imagine a can of spray paint. Even the cheap brands will work pretty well when you press the button all the way down, but will start to sputter and produce a blobby result if you only hold the button down halfway. The OS carb is like an airbrush that can produce a fine, smooth spray all the way down to its lowest flow rates, so you can achieve an idle that just isn't available on the stock carb

Edit: here's mine installed, it think it looks like it was always meant to be:
View attachment 199177

Nice
Thanks for the info,

 

[HDRIDER56]

You shouldn't have any issues with the metal OS 11K carb getting damaged like you're experiencing. The 11K carb at least for my experience holds a tune better. I found them to not be as finicky when minor needle adjusting was needed.

Like @Chubaka mentioned the Losi Carb is a rarity if found. Just be aware that they are a plastic bodied carb like the stock Traxxas carb.

Don't get the OS 11KR carb as it's equipped with the Traxxas Revo style throttle arm, not a ball end style like needed.

My revo carb has throttle arm with the ball on it. Should I get one without a ball? This isn't the 1st time I've seen it mentioned, curious if that's why the throttle isn't as smooth as the Jato

 

[CertifiedMike]

My revo carb has throttle arm with the ball on it. Should I get one without a ball? This isn't the 1st time I've seen it mentioned, curious if that's why the throttle isn't as smooth as the Jato

If you are experiencing binding in your throttle linkage, you can see it and correct it without your car even running.
If you have a tuning issue, its a different story.

 

[HDRIDER56]

Fantastic, I put it on my TRX-swapped MT and also put in a ceramic rear bearing, it idles super stable and runs better than it did with the stock carb - cooler, more powerful, and more responsive:

Can't figure out how to upload videos

 

[tudordewolf]

Can't figure out how to upload videos

I ues youtube and paste 'em here, I don't think this forum hosts them directly.