RS4 Racer

In my RS4 I have an os .15 engine and it is giving me some problems. I was wondering if I need to just get my engine replaced, or work on the adjustments some more. Here's the symptoms: Idle is nearly impossible to set; it is either too high or too low and if I manage to get it in the right zone, it will never stay there. There is sporadic engine shutoff. I'll be driving and come off from about 1/4-1/2 throttle and it will just die. The engine has a CVEC tuned Pipe and I run O'Donnel 20% Nitro. I would like to do a rebuild, but I'm inexperienced and might mess up the crankcase. The engine ran perfect and idle'd perfect for around the first quart of fuel and then it began to mess up. Can anyone help me? If you have any questions about the situation, just post them and I'll try to give you the best answer.

125cchyperman

Did you try a new glow plug yet. Did you try adjusting the needles at any time thought our the ordeal. How old is the engine, how many gallons have been run through it. Is the carb nut nice and tight, along with the header bolts.

There could be tons of thngs that can make this happen but lets start with the simple things first.

WalawalaStore

Hi,

OS engines are probably the easiest to tune because of high quality carburators. You will not need to rebuild after just 1 quart of fuel.

Check if the clutch springs are worn or too weak causing clutch engagement around idle.

Regards

Joaquim

RS4 Racer

Well, more than 1 quart of fuel has been ran through the engine. The car has been put up for so long that I can't even remember how much gas was ran through the engine. I was just talking about recently.

thedub88

make sure that the screw in the two servo horns isn't tight, they need to turn independantly. With the radio and reciever on, make sure the throttle arm (on engine) is all the way back to idle position. You can set the idle fine, but if the screw is tight, the first time you brake, the servo horns will spred apart (like they are sopposed to) but will stay apart when the servo returns to idle position, giving the engine gas. This could be the case, and making you think there's something wrong with the idle.

At idle position, make sure the two horns are directly over each other, not spread apart

RS4 Racer

The Verdict Is In:

I'm going to have to buy a new engine... The person who owned the car before me had the engine tuned to race and he told me that it was performing at its best level ever before he put it up. He stopped racing because he moved to GA and there wasn't any tracks near by. Usually when an engine is performing at its best level, its about to go. I think that when I ran a little over a quart of fuel through it, that put it over the edge. Its not too bad though. A new 15-CV from Tower Hobbies is only $99.99... Now I just gotta get a hundred bucks. I would normally feel a little ripped off, but I got a fully upgraded RS4 for $150.00!