In my mind, fuel lock is a cylinder with so much fuel in it the piston cant go over the top. If so, gotta pull the plug & spin it over, then change the oil. No start until the oil is changed.
Then, the carb needs work, so the needle seats & shuts fuel off when the float rises, maybe a float adj would be in order, too.

When you tried to push start it, did the tire just slide or did the motor spin over at all?

Try new spark plug, sometimes SOME PLUGS??? sparks fine when you earth it to the cyl head to test it, but for some unknown reason, won't spark when tightened down in cyl head and gets all wet with petrol. Take out your plug spin the engine a couple of times with the starter to blow  the excess fuel out of the cylinder, then put the NEW!!! plug in and try starting  with half choke and no throttle. ALSO CHECK OIL LEVEL IN CASE FUEL HAS DRAINED DOWN FROM THE CYLINDER INTO IT,,,CHEERS,,KENNY

P.S. Always use a new plug,,they work hard and are cheap enough considering the work they do

Once you pull the plug and turn it a few times check for spark while you got the plug out. if good or looks good, put back in prime the carb make sure your getting fuel, check oil, better to change it. then if still no start try a shot of starter fluid, see if she fires then, if mine sits for a few days sometimes i have to shoot it, just a little squirt is anough to bring her alive.  Does it sound like it wants to start or just turning over?

prechermike wrote on 08/26/09 at 04:34:35:


There are two remedies to this problem.
We don't necessarily ALWAYS have a new spare plug at hand.

1) Pull the plug out and "dry it" with a lighter or a match - that's to burn any possible fuel residue away;
2) clean the plug with a nail file (excellent handy item, especially the ones your missus will discard) to clean any carbon residue;
3) open up the gap from the recommended 0.4mm to about 0.8mm (you guys figure that out in 64ths inch)
What this does is to avoid that over-rich air/fuel mixture will soil (wet, foul) the spark plug before the engine's even started.
However, the plug will still spark.

The other remedy (which works wonders especially when occasionally touring high-altitude places) is to change the plug with a 3 or 4 pronged spark plug.
The 3, 4 prongs NEVER fire ALL together, there's only one firing at any one time,
BUT
you can foul one, maybe maybe two, never all three at the same time, and every single successful spark cleans the fouled prongs each and every time.



Take care, though, that the spark will fire downwards rather than sideways, so prolonged use of such a plug (meaning, many months) may result in a holed piston.

But, as a "once in a while" solution, it's magic...

You may want to check the decomp solenoid, make sure it is adjusted properly. Fuel lock? Never heard of it. Vapor lock, on the other hand, is a real thing that can happen on some older cars, preventing fuel from flowing. But that only happens on a very HOT engine, under certain circumstances. Not on a cold motorcycle engine. Yes, your mechanic is grabbing at straws.
I would check the float, needle and seat, clean carb, check fuel and vacuum lines, check petcock for proper operation, new plug, a squirt of oil in cylinder, and by all means, if there is gas in oil, it must be changed. (filter too) Make sure you have spark, and you should be riding.