I have a schumacher Swift and its playing up! Its starts first time every time not a problem. This morning i was running it on 20% fuel and it was running like a dream.

I put 18% fuel in (all i can get now) and it ran for about 3 mins before cutting out. I've tried all the appropriate tuning to compensate but the tuning is just way out. It is smoking like chimney all the time and yet when i put it to full throttle it just dies. This is obviously showing signs of being too rich and too lean?!?!?!

If i slowly ease the throttle on then it will make max power without cutting out but it sounds rough and smokes like crazy. Although the engine is screaming its not even going half as quick as it was this morning.

Any help would be greatfully recieved as its (not) driving me mad!

Cheers guys

It sounds far to rich. keep leaning the top till it runs well at high speed then lean the bottom till it picks up well.

Hi

You may have a bad batch of fuel, who is it made by.

try a different heat range glow plug, some fuels like certain plugs

hey guys thanks for the replies.

Well i took it to my local hobby shop and the patronising bloke behind the counter told me that it was all because it needed cleaning and he wanted £60 to sort it for me ($100)

I just walked out and i've decided that i'll give it a good old clean out tonight just incase then i'll start afresh.

Just to note i had another go today but it won't even start accelerating now it just coughs and splutters no matter how lean i make it. I'm Worried that my clutch maybe gone as if i do get the revs up it still just crawls along.

I have put a new glow plug in to no effect. I am beginning to wonder if it IS the fuel as mentioned. Its mixed by my local shop and it's 18% some people have told me this is too high but the previous owner was running 20% with no probs.

Once again thanks for replies and i'm grateful for you all sharing you knowledge.

18% is actually on the lower side. Most people run 20-25% and some 30%. It sounds rich to me. Loads of smoke and the engine producing poor power. I bet if you tip the buggy on its side loads of oil comes from the pipe too. The problems pulling off is too lean on the bottom,so lean the bottom needle.
Do you have a temp gauge? if so check it (if you get it running) and it'll be sub 200F You've changed you fuel so you really need to start again from near factory settings.

All so I do not recommend running fuel with more 12% oil content.

right i've just totally stripped the engine and cleaned it and theres no scratches or scrapes on either the piston or the cylinder so i'm assuming the engine is fine. (totally not what the model shop guy told me but i firmly believe he is a complete idiot any way!)

There was a fair bit of oil sat in the bottom of the engine though when i opened it and in my experience (1:1 scale cars) this could be what is slowing the piston hence robbing all my power.

I have to admit i'm relatively new to scale cars and as i bought this second hand i'm not too sure what the factory settings are. Are they default settings (ie. turn all needles fully one way) or does each engine have a specific factory setting.

by the way my fuel doesn't have the oil content on it just has a massive 18% sign in the corner so it could be the oil causing the problem.

thanks again guys keep the ideas coming

right just started it up and its running alot better but still cuts out (this was only on a stand and wheels arn't on)

I'm worried that theres a serious problem as even when i rev it the hubs (that the wheels attach to) don't seem to be spinning as fast as they should be.

right its all sorted now it turned out to be the centre diff was mangled so i stuck a couple of shims in and now its back to its awesome normal self again.

I did change the clutch shoes first thinking it was that but no joy but at least now its fixed and i have a nice new set of clutch shoes.