P1Fanatic

Heres hoping one of you fellow RC car owners can help my novice self.

I bought a Kyosho Nitro car from a guy at work last year and only used it a few times before winter. Needless to say that guy has moved on. I'm now having problems getting fuel to the carb.

Normally I press the primer button on top of the tank to generate some pressure to push the fuel out of the tank, through the fuel filter and on to the carb. Now the button doesnt appear to generate any pressure. Ive noticed the rubber seal ring on the plunger attached to the button has broken off and I thought this was the problem. However If I look at another old tank I have, the seal ring is on top of the plunger head so doesnt appear to offer any sealing benefits (to my uneducated eye). I would swap the tank but the way its positioned in the chassis means a lot of dismantling and a lot of the screws will need need drilling out and replacing as they been worn away by the tarmac (low suspension).

Does anyone have any suggestion before I take it into a pro shop and get them to sort it?

Simon.

Alpine

I may well be right off beam here... but I fly RC helicopters.. for about 5 minutes before I crash them and they lay around for months before being repaired and almost immediately crashed... more expensive hobby than a scooby!

Anyways... the fuel I use in the two stroke engines has a lot of lubricant in it which if you leave the fuel lines in place the fuel element vapourises and leaves a sticky mess blocking the pipes / carb.. The only way I found to sort this is to strip the carb and install new piping / or wash the old out with fresh fuel.. easier to replace the 3 inch pipe in my install...

don't know if this helps

Ps.. fuel pressure on the heli is caused by piping some of the exhaust into the top of the fuel tank..

Scrappy2

like you say - sounds like a compression thing... check for leaks in the fuel line, the exhaust coupler and gasket... If it's none of those and you are sure your fuel tank is ok it could be a worn piston or sleeve in the engine...

Scrappy2

when you've run the car and don't intend on using it for a while you should put some after run oil in the carb and the chamber... Like Alpine says, fuel goes off and leaves a nasty mess inside model engines....

Paulo P

iTrader: (42)

just had mine out at work this afternoon and had the same problem at first (hadn't been run for 14 months). Just kept trying and eventually it started what type of car is it? mine is the kyosho landmax and sometime a drop of fuel in the carb air intake or in the bore (take the glow plug out) is enough to get the engine to fire and draw the fuel in on its own

P1Fanatic

Thanks for the quick replies lads. Good to know theres a few peeps on here for advice.

It definetly seems like a pressure problem. It could well be the fuel pipe as its looking old. I can simulate pressure by disconnecting from the carb and sucking the fuel up but if I stop and carry on with the primer button then the fuel just returns to the tank. Im thinking its gotta be the seal on the primer plunger as it worked fine before this broke - ive tried prying it back over the plunger with some small tweezers but its impossible to do with so little space to manouever. So I think replacing the fuel tank is the only way forward

I may just take it into the RC shop next week and get them to do a complete check and service on it whilst Im away in the states for 2 weeks. Will also be a good excuse to swap the Scoob shell for another new one as its looking a bit battered

Simon.

Paulo P

iTrader: (42)

P1fanatic

you can also try priming the engine by taking the exhaust pressure hose off and blowing into that. I guess from what you are saying that you have the 1/10th subaru?

Nikko2

If you are trying to start it on a starter box and your tank is pressurised from the exhaust. Just put your finger over the exhaust for a couple of secs as its turning over. You will push plenty of fuel through.

Nick

P1Fanatic

Paul - not its a 1/10 Porsche GT2 with a Scoob shell.

Ive dismantled all the fuel pipes and cleaned them in new fuel. Ive also submerged them and then pushed air through to see any holes via air bubbles but there are none. Ive primed the engine with fuel as suggested by squirting a bit in under the glow plug and nothing (the glow plug is new and heats up fine out of the engine). Im using a glo starter and pull start to turn the engine but it doesnt even remotely sound like catching.

The exhaust pipe - well it goes from the side of the fuel tank to the top of the exhaust (from the manual this looks like an upgrade as its 3 times larger than the one shown in diagram). How will blowing into this prime the engine (please excuse my ignorance of engines)?

Simon.

Paulo P

iTrader: (42)

P1fanatic

Maybe being stupid here but have you tried adjusting the mixture? those 1/10th engines GX12? are critical on mixture setup. I also have a peugeot 306 with that engine and it can be a real g1t to get going somtimes. the manual says open the needle 3 turns I believe but if I remember correctly 2 1/2 turns works well.

sillysi

Mixture is indeed critical. Mine uses a GX12 and the manual does say start at three turns of the needle. Mine will not start set at three turns, I can happily pull the starter all day with no joy. I now have it set at one turn out and it starts after about 10 pulls from cold and about 4 after a new tank of fuel (still warm engine). If I have it running on a bench and try to turn the mixture out to three turns the car just stalls when I apply throttle. I still get plenty of smoke when running the car so one turn seems to be ok.

P1Fanatic

Hmm its an older GS11x but must be pretty similar. Manual says 3 turns from closed counter clockwise. I will try 2 1/2 and lower.

mega_stream

Take off the primer button, don't use it.
Put a finger over the end of the exhaust pipe and pull the starter slowly a few times. Fuel should go into the carb.

If it don't start, replace the glow plug and make sure the battery is fully charged.

That should ge it started....if not poor some fuel into the cylinder and try again. If the starter gets harder to pull its flooded, the extra fuel should be spat out the exhaust, try again.

Bu99ers to get going, but damn good when they run

Good luck!

mega_stream

Oh, just read the rest of the thread....
All these tips come from Paul

Cheers for your help when I had problems with mine Paul

acme

try these.......
put car on a stand,
full tank of fuel,
air filter off,
cover carb with thumb,
if its a pull start then pull it a few times...fuel should start to get sucked in......if its a starter box do the same with out pull start,
let it run for 1/4 tank fuel for warm up,
lift one side of the car up ( if exhaust on teh right life the left handside if on the left lift right handside ) so the exhaust is facing the ground ( make sure the outlet is facing the ground too ) and rev the bugger......if there is green ish yellow sticky oil spitting out then rev it till there aint none left,
by now u should have 1/2 tank of fuel left,
then run the car like there is no tomorrow and rev it as hard as u can and do loads of silly things with it to make sure its still running like it should.....also this helps lose it up after a long sleep,

there is something that might help keeping ur car in 'better' state after each run

befor packing things up,
leave 1/4 tank fuel,
lift the car so the exhaust is facing the ground,
and let it run.....there should be some ( or none ) oil spitting out.....if there is oil spitting out then rev it and let it run till there is no more fuel

also there is a tip for fine tuning ur engine
car on stand
mixture needle open for 3 turns,
start the engine and make sure it keep running
start closeing the mixture needle very slow
and the engine should start revving up with out u doing it
and soon u will make it too lean and the engine cuts out
then turn the mixture needle up by 1/2 a turn
u should be in the best mixture setup ( if not u can turn up or down the mixture from there )

hope these helps

mmmmmm
juz asking........what kinda cars do u guys have?

i run a old model Kyosho Super10 ( with a few things upgrade )
wanna trade in for a newer Super10 FW-04

anyone running the same as me?

P1Fanatic

Mine appears to be a super10 with a few extras im guessing by all the manuals I got with it:

Uprated Exhaust
2 speed transmission
Aluminium flywheels and the like
Toe/Camber adjustment plates.
Oil Filled suspension dampers
Load of other suspension **** that I have no clue about

Got 4 sets of slicks and one set of wets, 2 shells (1 porsche GT2 + 1 Scoobie WRC), receiver cover, loads of spares like drive belts, glow plugs, suspension rods, bumpers, etc. Was a good deal including fuel, rc unit, glow starter etc for £100. Pity I dont have a clue what half of it is Bought it off some geeezer at work whose son was upgrading to some uber nitro car which I cant remember the name of now.

Simon.

mega_stream

Stick with it m8, you'll get it sorted eventually
They are great fun, a bit of a pig to get running right, but when they go.....shyte they do go!

Generally find the guys in the model shops are very helpful.

acme

super10 eh?

well i can tell u what u can use for the all the other bits and pieces u got

i got a few mods done to my one too
carbon upper deck , countersunk chassis , springs/shocks, OS engines , 2speed , reciver cover , carbon streeing plate , BB all round , stablizer etc etc

where bout u live? i live in bedford maybe i'll give u a run sometime eh?

hehe

P1Fanatic

I live in Histon just North of the A14 above Cambridge. If I can ever get the damn thing working Ill be up for meeting up. Hehe a Scoobynet RC owners meet Dont expect any l33t driving skillz from me though as Ive only managed to run the thing 4-5 times and then its been in me cupboard. Wanna get it sorted as the work car park would be ace for racing it at weekends.

sillysi

I have a Kyosho Nitro Scooby which developed the same fault after a winter storage. I discovered a very small hole had appeared in the fuel pipe which after replacing sorted the problem. It would be worth checking the fuel pipe and the return pipe for any leakage. I think you do need a go seal around the plunger to create the pressure, but not sure it may be just to stop fuel leaking out. I will try mine tonight with the fuel cap open as this should simulate a damaged ring (LOL). The screws are a real bugger when worn down!

You can take the pipes off and blow down them to check for any blockages, I have blocked mine before by leaving fuel in the car. Some chaps I know fill theirs with a very thin oil to keep the car lubricated when not in use.

[Edited by sillysi - 4/10/2002 4:05:49 PM]