help needed desperate please

[byh0005]

i have recently bought a 1973 Kawasaki g5 and it wont start it has spark good compression fuel is getting in the carb because i can smell it in there and the hose has no blocks it just wont start i don't think fuel is getting into the cylinder please help BTW it is a 2 stroke
any question don't be afraid to ask i really need help

 

[motovert24]

did it start when you got it

 

[Motovert Pro]

after you have kicked it over a few times check the plug to see if fuel is making it to the engine,id bet the needle and seat are all gummed up in the carby preventing fuel from passing through.its a common problem with 2 strokes that have sat around for a while,the fuel evaporates out of the system leaving the oil behind

 

[sean01]

yep sounds like a carb issue. also wat colour is the spark its producing...its very important..

and if the plug is getting wet then there are chances that you have a heap of fuel sitting in the crank area...very common also...

take the plug out and put it in top gear and push it around for a bit, and keep an eye on how much fuel comes out the plug hole.... oh and be sure to make sure the fuel tap is turned off...
and on some bikes depending on the design of the exhaust pipe, you need to remove the exhaust as fuel can sit in there also..

 

[klx ragger]

befor you start rip in carbs down try a new plug ive had this problem before i had a spark petrol getting through i must of riped the carb down 6 time checking everything a mate told me to put a new plug in after 30 Min's of arguing the toss the plug in there has a spark and was fine he put one in and fcuk me first kick it started.worth a try bud

 

[byh0005]

to answer some questions it didn't start when i got it and it has a blue spark

 

[thump*140]

how old is the fuel in the tank? was it mixed properly? is it a premix, or oil-injected engine? (i'm guessing oil-injected being a road bike?)
if it was premixed, did you slosh the jerry can good and proper, or just pour oil into the jerry can after fuelling it up?
Have you opened the carby drain screws with the fuel taps on to see if you are getting decent fuel flow?
stupid one, but easy to mis-diagnose... is there enough fuel in the tank to actually create enough pressure to flow fuel PAST the carby and into the inlet manifolds and through the reedblock?
If you have a big fat blue spark, good compression and fuel at least at the carby, i'd suggest either your jets are blocked up, and not allowing fuel anywhere past the float bowl, or your using a poor starting technique...
you said you can smell fuel... is it clean fresh fuel, or does it smell stale? (yes, you'll know stale fuel straight away when you smell it, it smells a lot different to fresh fuel...)
might even be worth draining the tank to see if there is any water in it, which will also create issues...
if after all that it still doesnt work, take the tank off, up-end it all over the bike, and set fire to it..

 

[aldo]

when me and my mate used to go riding his bike wouldnt start on a cold spark plug so we put it in my bike for 5 minutes took it straight out put it straight in his and it went first kick other than that i have no idea

 

[byh0005]

the fuel is fresh im getting a big fat spark mixed properly enough fuel i think it must be the jets that r blocked so i will get that cleaned and try again

 

[Cactus Jack]

Remove the plug , spray some fuel into the bore , replace the plug and give it a kick ... if it fires or tries to fire you'll know whether it's the carb or not ...

Two strokes need good ring and crank case seal to work properly ... they don't pull charge in on the down stroke of the piston like a 4 stroke ... they pull it in on the upstroke ... The underside of the piston compacts the crank case volume on it's way down and forces it up thru the transfer ports ... but ONLY if there's no leaks past the rings OR crank shaft end /case seals ...

In a lot of cases with old engines , the rings and bore are worn out of round so the engine lacks compression and won't start ...

Kooks who think they can extend the recommended time between 2 stroke ring changes don't understand that they wear out of round because they are pinned in a fixed position on a two stroke piston ...

As a result ... they wear a lot more where they run all the way up and down the bore between the ports and a lot less where they run over the ports ... After a while , they only touch the cylinder walls above and below the ports and are held off the bore in between the ports ... resulting in a huge compression loss ...

That's what's wrong when you hear a bike going b'woar b'woar b'woar .... wiiiiinnnnggg ... b'woar b'woar b'woar ... He he he ...

In a lot of cases with the older iron bores ... the cylinder gets worn more between the ports too ... with tapered wear above and below the ports ...

So when new rings are put in an old bore ... the engine can also exhibit the above symptoms ... even IF it was still running OK with the old rings in it ... That's because the shape of the worn rings suited the worn bore ... allowing the engine to work ...

The main reason for doing regular ring changes in a two stroke is to keep the bore ROUND and prevent the rings from bulging into the ports and chopping away at the top and bottom of them ...

A '73 model two stroke is BOUND to have a corrosion damaged or worn bore ... unless it was recently reco'd ... Another thing to check is the crank ... IF you can feel up and down or front to rear play ... compression will be leaking out thru the end seals ... Blowby from running worn rings causes the seals to harden and lose their ability to seal ... the excess heat can also warp and distort the crank cases ... rendering the engine un-rebuildable ...

You can tow it in gear behind a car until it starts ... but it will bog and die in the ass if you let the revs drop ... If you're lucky it'll start running better when it heats up a bit ...

I hope you've fluked it and gotten an engine that's still in good running condition though ...

Let us know how things pan out ...