VX-16 Low RPM issue.

[ArchmageNydia]

Hey guys, my Redcat Shockwave has been serving me fairly well for a while, but I've run into a problem. As the title states, the engine is not revving nearly as high as it should, so it only goes to a crawl on full throttle. The high-speed screw is in the same place it was when it was optimally tuned, and it seems almost like it's just running extremely rich.

I believe it has something to do with the fact I hit a bump in the road and flipped the car, so the engine flooded before I could get to it and turn it back over or stop it. I'm not sure if this affected the engine or carb in any way, as the body was on, and I see no damage to the cylinder or any other part of the car related to that.

I have a decently old glow plug in the engine, so that may simply be why, but it starts up fine and idles perfectly alright, so I don't know if that's the issue.

Any help would be appreciated! Thank you!

 

[watertrucker]

You might check your linkage and make sure nothing is binding. Also check your servo horn to see if the screw worked loose. I had one come loose recently and it affected the throttle and brake action.

 

[Certified Mike]

I would go thru the very simplest things first, just to prevent you from chasing your tail. Replace the plug and eliminate the question. If there is a fuel filter, clean, replace it bypass it just for now. Make sure your fuel is fresh. If there is ANY question as to it's health, just get a new bottle and use that.
Verify that your fuel tank cap is still sealing correctly after the wreck. If it is not sealed, it will cause all sorts of bad issues... Sounds likely that your issue could be caused by that as well. Verify that your servo and linkage is moving correctly thru the entire stroke or cycle (full forward and back) making sure that the servo or arm did not strip or loosen up during the crash as @watertrucker mentioned above. Remove the air filter. Verify it is cleaned and oiled as needed. While it is off, look down the throat of the carb and operate the throttle. Make sure it is moving the internals properly as well.
I would bet that following thru this, your issue will become clear. Let us know how you have done. If all of the above hasn't cleared it up, we can move forward with more in depth possibilities.
Good luck!!!

 

[NinoS]

Worth adding something that happened to me last night. Started the 1/10 scale car, engine would barely rev up at all. So i checked the throttle linkage, it was barely moving. Checked all over for something holding it up, blocking it's movement perhaps brake linkage or something - could find nothing.

After a minute or two, realized my radio was on another model's preset, with 10% throttle setup for my son on a fast brushless RC. Doubt that's your problem but worth mentioning i figured!

 

[Certified Mike]

Yeah, I think after re-reading this, I would set my initial efforts towards a physical inspection of the throttle linkage (verify nothing is bent or damaged by the flip you mentioned.
Remove the linkage from the carb or servo. Operate the throttle from your radio and see if you have full movement from the servo. See that the arm is making a full sweep in both directions, that it is operating smoothly and without any noises (that it doesn't sound like your servo gears are stripped). Then move your carb linkage (by hand) and see that it is moving correctly. Verify that in both directions that the carb is opening and closing by looking down the throat of the carb. Make sure that this movement is also smooth and without any odd feelings, binding etc...make sure that when you move it back towards the braking that it is operating correctly, again, without any binding thru the entire motion. While I don't own a redcat, I have heard that the stock servos are somewhat prone to failure. This may be the issue.
Without adding too much pressure, see that you aren't able to cause any skipping by holding the servo arm and operating the servo with the radio. The servo arm may also be stripped as previously stated by @watertrucker .