no start, malossi 62cc

So i'll try to include everything i've done, hopefully someone can point me in the right direction.

78 magnum mkii. za50, rebuilt less then 500 miles ago.

removed oil injection; intake, reservoir, pump, little black thing, worm gear. Make a block off plate from a scrap steel computer case, reused gasket, m5 hexnuts.

removed old running stock head, cylinder, piston, gaskets.

filed, sanded malossi cylinder skirt, slides in no issue.

washed all parts in two stroke fuel, lubed using 2stroke oil.

piston ring within spec.

1 paper base gasket, cylinder and piston in , windows facing intake port.

DMP high comp head, 2 metal head gaskets.

torqued 1.2 KGM (8-9ft lbs)

compression 230psi.

proma GP exhaust, thick gasket, m6 long nuts.

intake is malossi.

carb 15.15 SHA, cleaned, several times. 78 jet, #50 choke plate. Carb sits at a funny angle till new intake shows up in the mail. filter is stock. i have a high flow, but it won't fit in there with the current intake.

replaced all fuel lines, added inline filter.

spark plug is bosch platinum 4214, gapped .016 (and i've tried 4 of them)

points checked, and rechecked, .016, didn't muck with timing yet.

checked spark with inline tester, so plug sparks.

I have tried and tried and tried, and it will not fire. i've tried 62-80 jets, choke, no choke, stock filter, no filter. recheck points, reclean carb.

The bowl is always full when i go to clean and or change jets, i can smell fuel in the head.

what the hell am i missing. i have compression, i guess i can try rolling back to the stock head. i have fuel, i have spark. i just keep ripping at it, over and over and over, and while rarely it feels like it's gonna fire, it still never does.

I have to be missing something. but what.

Re: no start, malossi 62cc

I dont know what type plug that is but I've always used NGK b7hs plugs. Make sure you have spark, and make sure everything is snug to prevent any airleaks. Stick around the 70's range for jets as well.

Re: no start, malossi 62cc

how are those bearings and pucks on that 2 spd?!

Re: no start, malossi 62cc

You don't need two head gaskets. You probably have shitty compression.

Re: no start, malossi 62cc

Missed your 230 psi compression. That a lot dude.

What about trying to start with the choke? Have you sprayed some starter fluid into the cylinder and tried to kick it over?

Re: no start, malossi 62cc

yeah, i added the second when i was close to 250. i was actually kinda shocked when the gauge went that high. i have some starter fluid somewhere in the garage, i'll have to find it, but i'll give it a shot.

Re: no start, malossi 62cc

My guess is that if you have fat spark and good compression, then it's something to do with your carb not delivering fuel. Or you are just flooding it. Change out the plug and try to start it with the choke on. Wants it kicks over and runs for a second with the choke, try it with no choke...

Re: no start, malossi 62cc

yeah, i think it has to be something in the carb. i have spark, hell i check in between every change to make sure something's not missing. i have compression. i rolled back to the stock head and it's about 155psi now. i got it to sort of turn over with a #70, but by that point i'd already managed to rip the clutch cable and tear off the left pedal.

I'm just gonna have to sit on this until the new intake comes.

i wonder if my block off plate for the injection could be an issue. hell i dont know at this point, i either need another set of eyes or a break to rethink it. i've never had this much issue starting a kit before, it's driving me mad.

Re: no start, malossi 62cc

Yeah. I've never messed with anything that has oil injection. I would think though that as long as it's sealed up that it isn't your problem.

You checked for air leaks by spraying carb cleaner on every possible spot it could leak, right?

Re: no start, malossi 62cc

try a b7hs. maybe that platinum plugs resistance or whatever is causing troubs

Re: no start, malossi 62cc

so just to bring this back to life.

i switched out to the stock #4 head, which took me to around 150 psi. so i ordered some additional head gaskets, popped the high comp head back on and we're now somewhere between 180-190.

replaced the outer clutch cable.

checked the rings, wear, etc. re-lubed. re-tourqed.

new intake came, ordered a new 16.16 SHA too just for the hell of it.

replaced spark plug wire, confirmed super giant blue spark.

tonight i'll attach the intake and carb, and i guess we'll see what happenes

Re: no start, malossi 62cc

so it was the damn worm gear. i put the oil injection worm gear back in and it fired right up, first kick. now i gotta figure out why that is.

Re: no start, malossi 62cc

That worm gear assembly seals the crank case ...if you take the whole thing out, you expose the bottom end to a huge air leak and you will not get any intake of fuel ...put back the piece that the worm gear rides in and your block off plate and your motor should run ...its best to fill that tube with epoxy to take up case volume...

Re: no start, malossi 62cc

Problem solved.

Re: no start, malossi 62cc

nothing to add just the 16:16 sha is my favorite carb ever

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