Jato 3.3 running or trans problem??

[Shadow jato]

Help I have a problem I'm not sure if it's a tuning problem or a trans problem

Here's what it's doing every now and then at low speeds it Boggs down like no other then I'll get it up to speed slow down to a stop and it's back to running like there never was a problem.

I'm thinking ether my low speed is a little to rich or high speed may be a little rich or maybe my trans is getting stuck in second gear if it is then how can I convert it to a single speed.
I really don't need 2 speeds as I only use for off road

 

[Shadow jato]

Does anyone have any suggestions

 

[goodgamer]

Probably a tuning issue. Have you messed with the tuning since it started doing this?

 

[Rolex]

Bogging at the low end is usually a good indication that your LSN is set too rich. Lean it just slightly, run it around to give it a chance to clear out. If needed, keep doing that till you get a consistent take off.

 

[Shadow jato]

Ok thank you I'll give that a try and no I haven't had time to mess with it due to work.
How about trans conversion to single speed how would I do that I feel I don't really need 2 speeds as I only use for off-road bashing and never really any on road except when tuning then I'm back to off-road fun lol. So I figured if I had a single speed I could get more out of it in low end

 

[hamz9561]

Turn it in small increments like the hours on a clock. Just one hour at a time.

 

[Shadow jato]

I have my idel turned in all the way any lower and it dies when I brake.
And the low speed needle seames to be turned in all theway as well and it will idel fairly steady and consistent. And when I pinch the fuel line it dies in 3 secs with only a little rpm rise. It does move forward without pressing the throttle but I can hit the brake and it stays and takes a bit before it will die.
And If I get it moving at 5 10 miles an gr I can nail the throttle and it accels like no tomorrow. But from a stop it bogs down.
Then today it was doing great still sluggish from stop but I was running it in the back yard jumping it a few feet it flipped a few times but never died. It really starts bogging down after about 10 15 mins of running and it's at 250•f I'm told that's a good temp for bashing
If you need more info let me know.
And if anyone can help I would really appreciate it

 

[hamz9561]

You should have an idle gap of about 1mm or the thickness of a credit card.

 

[Shadow jato]

With the brakes pressed or just idel no brakes? Because with the brakes pressed that's where it's at

 

[Shadow jato]

So I think I figured out y I've been having tunin problems i checked my compresion and that seams good. I was driving it around it started running like dog poop agin I brought it in and took the air filter off and I coul see fuel bubbling past the throttle piston.
So could that be why even tho I have my low spee turnd all the way in its still running rich? I know it can cause that problem with real cars but I'm still kinda new to rc cars so I wana be sure before I reseal everything I have a poop ton of rtv so I may Resealing anyways when I have some down time tomorrow.
When I am Resealing the engine what is the best way to clean it and what is the best type of product to use?

 

[BillyC74]

You say your fuel was bubbling, do you mean boiling. If your fuel is boiling then I think that is your problem. You say it starts acting up after 10 minutes or so, I have an engine that was doing the same. The cause of it was the fuel boiling. Try running it cooler, maybe 220 instead of 250. That helped mine.

 

[Shadow jato]

Yea it was at 250ish. It's kinda hard to keep it that low tho when I'm running in my back yard that's not that big lol. And it would start at 220ish then get worse the warmer it gets. And when I richin my high speed to keep my temp down it runs like crap. And the only way it's been performing anywhere near good is with the low speed nedal all the way lean and the idel gap really big and I still get what looks like to me to much fuel bubbling up top of the carb piston by the air filter.
So it makes me think air leak. Are there any other sines that will point I air leak or could I be wrong.

 

[BillyC74]

Well sealing it up sure won't hurt. I use Permatex high temp somethin, somethin.

 

[Shadow jato]

I'm going to Reseal it tomorrow as long asi get off work on time and my wife don't come home tomorrow lol and I'll retune after that and hope for the best.

 

[Nitro Nerd]

With the brakes pressed or just idel no brakes? Because with the brakes pressed that's where it's at

Okay, so a few things.

1. Your carb gap should be the same at idle (nuetral) and when the brakes are applied. I'd recommend setting all your idle trim back to normal and resetting everything.

2. If you are certain you have it set up correctly, but when you give throttle it goes back to say...1mm, but when you brake it goes to .08 mm, go to the next step

3. Make sure that your throttle rod/ball cup is parallel to the ball stud on your carb. You can adjust the setting of the ball stud on the carb, but this is important to allow smooth carb opening/closing. This way your throttle will go all the way back to neutral (which again is the same as brakes applied). If you end up getting it set perfectly but your brakes are engaging, simply move the collar between your actuator out about .5mm. Then, trim your throttle out. This will disengage the brakes but still leave the carb gap at it's idle stop setting.

Link setups can be a bit tricky (and frustrating...but they have to be correct). If you guys would like me to write up a "sticky" for setting your linkage up correctly, I'm happy to do so...just let me know.

With that, before sealing it...set the needles back to stock. Make sure your linkage is correct, and re-tune. Start with HSN. Regearding the temps...go by what you see and hear. 250 might not really be 250. Temps should be a baseline. If you get it running perfect and its 260...than that is your ideal "temp".

Also, your glow plug. Rev engine with ignitor on. Let idle for a few seconds. Remove ignitor and if you see drastic decrease in RPMs get a new plug.

Regarding the pinch test...the goal is not timing how long it takes for the engine to stop..but instead how long it take before the engine begins to rev at a higher RPM. Ideally, pinch the fuel line, and count 1missisippi 2mississpi and at "2" the you should hear the RPMs increase. Be sure to pinch it as close to the carb as possible.

Finally...check your heat sink bolts, couplers, and tank seal. Turn the vehicle upside down with fuel in it and see if any comes out. You'd be surprised what a difference a good tank seal vs a bad one will make on engine performance. As noted, sealing it won't hurt...but encourage you to rule out other things before going that route.

I hope this helps. Let us know how it's doing--we'll get you going. If you have a video you can share, that will help us tell you exactly what it is.

 

[Cornholio]

I have my idel turned in all the way any lower and it dies when I brake.
And the low speed needle seames to be turned in all theway as well and it will idel fairly steady and consistent. And when I pinch the fuel line it dies in 3 secs with only a little rpm rise. It does move forward without pressing the throttle but I can hit the brake and it stays and takes a bit before it will die.
And If I get it moving at 5 10 miles an gr I can nail the throttle and it accels like no tomorrow. But from a stop it bogs down.

Your idle screw is set incorrectly and so is your LSN. Your carb should never close all the way when you hit the brakes, it should stay at 1mm.

 

[Shadow jato]

Sorry I've had no time I get back online I haven't reveled my engine yet it out and at work with me now and upon further inspection I found the carb gasket wasn't even being effective as it could be move before I started to take it apart lol so I figured I'd Reseal it.
I have high temp auto rtv a poop ton infact sitting in my tool box so I will use that.
But as far as this stuff for the Needles called green slime. Is it not the same as dielectric grease? Ps I put this stuff on my connectors because it prevents corrosion an helps keep water out. I also use this stuff when installing new O-rings on vehicles because it helps make sure the o-ring dosent get twisted or pinched.

I have not remove the needles but I want to make sure there good before I put the engine back on the car seeing as I have the engine out

Ps... Thank you nitro nerd that info will help me hopefully get a better tune out of my car it explains it a lot better than others I have read.

 

[Shadow jato]

Also if you could tell me what it is green slime does just so I know I'm not 100% I know what it is green slime does also I just got a few mins to spare and pulled the header off and it was filled all the way up with some blackish gray slime poop I'm guessing was oil from the last owner not having a good tune? Over rich maybe

By the way I've only had this car a month tops

 

[hamz9561]

The Green Slime is a non-adhesive seal that is on everything from carb needles to shock shafts.

 

[Shadow jato]

Ok so I went to the hobby store today after work to get o rings for my low speed needle the old ones wear torn. The guy asked y I need them adjusted said because when I was Resealing my carb back to the motor with rtv I checked my needles and found a bad I ring.
The guy freeked out and said rtv won't work on these motor because these motors run at to high of a temp and at to high I air pressure.
I told him that I've always done it this way before and never had a problem and that no the rtv I used has plenty of heat resistant more than the motor will ever reach I've used this stuff on yea gaskets rear and front main seals and intakes and valve covers.

But anyway is what tho guy saying true that I can't use it on this motor.
I would really like to know if I'm doing something wrong or not