go kart 100cc vortex motor problem

[filop]

hey people i just boufht a go kart 2 stroke vortexx motor 100cc .and im getting realy nerved .4 days ago it was runing but my carburator was mssing some rubber thing .taked out fixxed put it again since then dont works more .i have spark and fuel too it comes out of the carburator already .i dont know what too do .i hope sombody could give me one advice what too do.

[davyboy]

Are you using a Tillotson carb ? If so, have you reassembled it correctly ? If not, it's possible that the one of the gaskets and/or the diaphragm has been put in the wrong way around. Have a look at this exploded view here and double check your assembly once again.

Have you done anything else at all to the engine since it was last working ?

[filop]

no i just taked out carburator ,and i have one wallbro 32 .it gives spark i really dont understand ,and since i bought the kart i puted at flywheel a mark to know always if spark is coming at right moment..can the problem come from the clutch?

[davyboy]

Some questions.

o Was the engine running properly, without any problems through the entire rev range, before you removed the carb ?

o What exactly did you replace when you removed the carb ?

o After you've attempted to start the engine, have you removed the spark plug and is it wet or dry ?

o Have you adjusted any of the jets on the Walbro since the last time the engine was running ?

o Have you attached the pulse pipe that runs from the crankcase to the carb ?

o When was the last time the engine was fitted with a new set of crankshaft oil seals ?

You may also want to take a look at this page here.

[filop]

what i see on soark plug i puted new one but i catch it out and its wet.i just put new gasket between the carburator and motor cause i turned thd kart on and it jumped in rpm and carburator was regulated i didnt touched on needels .the pipe its attached .

[davyboy]

Originally Posted by filop

what i see on soark plug i puted new one but i catch it out and its wet.i just put new gasket between the carburator and motor cause i turned thd kart on and it jumped in rpm and carburator was regulated i didnt touched on needels .the pipe its attached .

There could be a number of reasons for what's happening here :

o The carb is not correctly sealed to the engine with the new gasket. Make sure that there isn't an air gap between it.

o Your jets are incorrectly set. Make sure that the low speed needle is set at 1 and 3/4 turns out and the high speed needle set at 1/4 turn out.

o The needle valve inside the carburetor is not working properly and not regulating the fuel. It could be that the pop-off pressure is incorrect or the valve and seat have failed. If you check out my earlier link it will explain how to check for this.

o The crankshaft oil seal are worn. This will mean that charge escapes there and doesn't enter the combustion chamber... it will give erratic revving similar to what you suggested when you started it first time. Find out when they were last replaced.

o The engine timing is incorrect. I don't know what it should be on your Vortex, but as a starting point, around 2.2mm before top dead centre should be about right - check this.

o Is it a reed or a rotary valve engine ?

[filop]

its a rotary vAlve .this motor just runned about 2 hours and the thing i see here for me just could be carburator or somthing .the internal rotor de magnetics dont look so good.too but the weards thing is that it runned before taked the carburator that i dont understand ant motor have compression

[davyboy]

Check my suggestions above... there's a good chance it's one of those.

[filop]

thank you .but that with carburator there was no gasket between motor and carburator.that could be one of the reasons of the rpm.

[filop]

i just taked carburator out and i found down of my wallbro 32 this diaphragm like this is it possible that my motor dont works kause of this
http://imagizer.imageshack.us/v2/150x100q90/c/46/ki6h.jpg[/IMG]

[davyboy]

Originally Posted by filop

i just taked carburator out and i found down of my wallbro 32 this diaphragm like this is it possible that my motor dont works kause of this
http://imagizer.imageshack.us/v2/150x100q90/c/46/ki6h.jpg[/IMG]

I'm really sorry but the image resolution here is too low for me to see if there's any damage there. Can you upload a higher res version so I can take a look ?

[filop]

try here please http://imageshack.com/i/0fywukj

[filop]

http://imageshack.com/i/0fywukj

[davyboy]

is the edge of the diaphragm closest to the camera torn ? It's really hard for me to see. Otherwise it looks OK to me. That's not to say there isn't a leak or something there which would cause a problem with the pop off pressure.

You said that the motor has 2 hours running time on it. If that's race time, that would be about the maximum allowable before a rebuild. Do you know when the oil seals were last replaced ? Do you know when the main bearings were last replaced ? Is there any up/down movement with the crankshaft if you push/pull it with your hand ?

You will need to go through my suggestions above and rule them out one by one.

[filop]

i opned the motor today the ring around the piston and the piston are new crankshaft i did that and nothing .there us new gasjets on the motor and looks everithing where it should be like 100%.could be that the rotor is bit broked taked one timr out and it was bit burned at one side but i have spark .the only thing i thing its the spark cable when i put it on the spark plug could be that dont makes contact more could be possible?

[davyboy]

Originally Posted by filop

i opned the motor today the ring around the piston and the piston are new crankshaft i did that and nothing .there us new gasjets on the motor and looks everithing where it should be like 100%.could be that the rotor is bit broked taked one timr out and it was bit burned at one side but i have spark .the only thing i thing its the spark cable when i put it on the spark plug could be that dont makes contact more could be possible?

If you've ruled out everything to do with the carb and the main engine stuff [i.e. oil seals, main bearings etc...] then move on to the ignition system. Before you start down that route, I have to say that the PVL or Motoplat ignition system that you will be using are normally very reliable. It's rare for the kind of problem you're experiencing to be there... in any event, here's some suggestions for you.

Both of these are sealed electronic ignition systems, so there isn't a lot you can do to 'fix' them if they're faulty. You need to check the following :

o If there's a kill switch, ensure that all the wiring to/from the switch is good as well as the switch itself.

o Ensure that the wires to the spade connectors on the coil aren't damaged/crimped etc...

o If the coil is on rubber mounts, ensure that the earth strap is good and correctly fitted.

o Lightly sand the spades and the inners of the spade connectors on the coil and make sure that they make a good connection.

o Unscrew the plug cap, cut the lead back about 5mm and re-screw it back in to make sure it's made a good connection.

o Ensure that the connection between the plug cap and the plug is good... replace if in doubt.

o Ensure the rotor is not moving/loose on the crankshaft.

o Ensure that the stator is not moving on the crankcase.

o Ensure that the rotor is not touching the stator.

Ideally you ought to remove the stator and ensure that there is no damage to the exposed metal elements... but if you do this, you will need either a timing gauge to ensure that the timing is reset correctly... or make marks on the stator/crankcase so that you can line them up where they were.

If you're using a PVL system, there are two available - one is for karts and operates with an anti-clockwise rotation. The other is for motorbikes and operates clockwise. I know it sounds obvious... but double check that whomever sold you the engine didn't slyly fit the wrong one.

As I said earlier, the problems you're experiencing are more often than not carb related. The Walbro is not a good carb for a kart engine, although some people do use them. The Tillotson is much better option and the vast majority of people with your engine will be using a Tillotson.

Hope this helps.

[filop]

thank you for your help .but problem of tillotson it just have one place to fixx the petrol pipe i have two one comes from tsnk an de other gos down direkt to motor

[davyboy]

Originally Posted by filop

thank you for your help .but problem of tillotson it just have one place to fixx the petrol pipe i have two one comes from tsnk an de other gos down direkt to motor

That's not a problem. The pipe that goes from the Walbro carb to the crankcase is called the pulse pipe. It acts as the fuel pump to draw fuel from the tank by pulsing the carb diaphragm. You can block that off at the crankcase as if you use a Tillotson you won't need it. There should be a tiny hole on the carb manifold on the engine than lines up with a similarly small hole in the Tillotson carb... this does the same thing, albeit simpler.

[filop]

thanks .and one more question have been listening that its possible to put one on board starter?! is it possible to do?

[davyboy]

Originally Posted by filop

thanks .and one more question have been listening that its possible to put one on board starter?! is it possible to do?

Anything is possible... but you would need to do such a significant amount of re-engineering that it would be madness. If TaG ['Touch and Go'] is what you're after, then you're better off buying a Rotax Max.

[filop]

is it a TM kf3 good engine?

[davyboy]

Originally Posted by filop

is it a TM kf3 good engine?

Before I answer that question, I need to know where you're located. In most parts of the world, including the UK, the KF classes have been a failure and I don't want to advise you on something that you can't use for racing.

[filop]

im not in uk im in germany i live here

[davyboy]

KF3 was a formula introduced by the FIA a few years ago for junior drivers, aged between 13-15. It was targeted at the Rotax Junior Max and Mini Max audience. However drivers didn't move across to it, preferring to stick with what they were used to. As a consequence it failed at club and local level and these days it's only really present at top national and international championships. From what I understand, ADAC Masters run a KF3 National championship in Germany but I don't believe the class is popular at club level. You might want to check yourself.

In terms of the KF3 engine - it is more complex, less reliable and more expensive to run in comparison to a Rotax Max variant. However you can often pick them up cheaper that a Rotax.

If you are considering going the TaG route, then my suggestion would be to choose Rotax. If you're aged 16 or over, you can go directly into the Senior Rotax Max class and use one of those engines. If you're under 16, then you would need to choose Junior Max or Mini Max engine depending on your age.

Hope this helps.

[filop]

now i just solved the problem and i got another one that it hapened before i have ""new used"" motor same motor bought it for 100€ .but i turn the kart on and the rpm jumps like motor is going to blow up it hapened with hold motor too i think my carburator is not right.its a wallbro and the needels are right and i puted gasketnew one i dont know what can be...
i just saw that the pipe wich cames from the tank goes to the side of carburator and the one wich comes from motor goes up to the carburator is it right?