R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Offroad Nitro Engine Forum (https://www.rctech.net/forum/offroad-nitro-engine-forum-157/)
-   -   Stuttering engine (https://www.rctech.net/forum/offroad-nitro-engine-forum/1136887-stuttering-engine.html)

wely324 10-06-2025 08:35 PM

Stuttering engine
 
My engine started to stutter as I’d open the throttle, making it richer didn’t help. I noticed my vent line had rubbed against the flywheel. I replaced it but same issue. Put a different motor in, same issue. I’m wondering if the fuel tank is clogged or something?

petersen114 10-07-2025 03:21 AM

I would replace the fuel tank and all lines.

Roelof 10-07-2025 04:39 AM

If it is the tank with like a small leak on the cap (that can happen) then still richen the engine would help. I would look into the exhaust, replace it or do a proper cleaning on the inside.

wely324 10-07-2025 05:13 PM


Originally Posted by Roelof (Post 16218904)
If it is the tank with like a small leak on the cap (that can happen) then still richen the engine would help. I would look into the exhaust, replace it or do a proper cleaning on the inside.

it may have been the exhaust vent nipple clogged. Hard to say, but it’s not clogged as of now.

unfortunately the new tank I installed had a small crack in the bottom and started leaking right away so I couldn’t test today :(

Roelof 10-08-2025 12:50 AM

Seen it several times that a small piece of exhaust coupling rubber snapped off and got in the pipe giving all kind of weird behaviour.

wely324 10-28-2025 10:01 PM

So I finally got a sealed tank, new lines, fresh plug, etc. Preheated the engine, it idled fine, but would die as soon as I'd open the throttle, leaned the high end needle by an hour, didn't help. Continued to try to get the motor to idle after opening the throttle but obviously went wrong somewhere. Pretty sure the engine is cooked now. Will see in the morning when I open her up. Pretty bummed out as I really liked my nova. It's so odd, I went from my reds running great on 20% and the next day it not. Didn't think it was the fuel, so decided to run the vp 20/9 in the nova. And now Im so confused on what caused this aside from my lack of experience or knowledge. The vp quarts are sealed and stored in my garage. so their should be no sunlight issues. Wish bones brew didn't go out of business.


Roelof 10-29-2025 01:47 AM

Swap the carburettor or take it apart, clean it all, check the O-rings and put it together.

One time I had such an issue and after some trying I took the carburettor apart and a small piece of the fuel line was in the housing of the main needle. Probably it snapped off when putting the fuel line over the tank nipple. I must admit I did drill the nipple up to a slight lager bore giving a sharp edge on the nipple

wely324 10-29-2025 08:11 AM


Originally Posted by Roelof (Post 16223565)
Swap the carburettor or take it apart, clean it all, check the O-rings and put it together.

One time I had such an issue and after some trying I took the carburettor apart and a small piece of the fuel line was in the housing of the main needle. Probably it snapped off when putting the fuel line over the tank nipple. I must admit I did drill the nipple up to a slight lager bore giving a sharp edge on the nipple

not sure how this happens
https://cimg0.ibsrv.net/gimg/www.rct...779f03cb3.jpeg
https://cimg1.ibsrv.net/gimg/www.rct...cee7547b4.jpeg


Roelof 10-29-2025 09:04 AM

Wut???????

Is that from the airfilter? Or dit you loose the airfilter just before the issue started?

wely324 10-29-2025 09:10 AM


Originally Posted by Roelof (Post 16223640)
Wut???????

Is that from the airfilter? Or dit you loose the airfilter just before the issue started?

no signs of dirt. Looks like g clip fell out. Those are metal shavings, I assume from the wrist pin wearing on the sleeve.

wely324 10-29-2025 09:14 AM

Seems like this issue, is separate from the original. Will need to have the reds engine inspected now.


Roelof 10-29-2025 11:02 AM


Originally Posted by wely324 (Post 16223646)
no signs of dirt. Looks like g clip fell out. Those are metal shavings, I assume from the wrist pin wearing on the sleeve.

Then there must be a lot of scratch markings up to a whole groove on the inside of the sleeve.

petersen114 10-29-2025 12:51 PM


Originally Posted by wely324 (Post 16223626)

That’s crazy

Bud 10-29-2025 01:17 PM

I don't know how that thing even turned over! Wouldn't have much longer.

petersen114 10-29-2025 01:22 PM


Originally Posted by Bud (Post 16223710)
I don't know how that thing even turned over! Wouldn't have much longer.

Right! Not to mention that he said it idled fine.

wely324 10-30-2025 04:46 AM


Originally Posted by Bud (Post 16223710)
I don't know how that thing even turned over! Wouldn't have much longer.

It eventually jammed up the engine and wouldn’t turn over. It originally fired right up, but wouldn’t hold idle. I leaned it but was acting funny spitting fuel out of the exhaust but sounding lean. Blipping the throttle it died and when I went to restart it was stuck.

Bud 10-30-2025 10:34 PM

I don't know whether to say you're lucky it started or you're unlucky it started. That looked like a wonderful opportunity to break a rod.


All times are GMT -7. It is currently 09:17 AM.

Powered By: vBulletin v3.9.3.9 Patch Level 3
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.