Following a leak of petrol in air filter and exhaust and checking float bowl, now cannot pull the cord to start it. Checked blade it was going round but not now. Cleaned debris. Could it be linkages?

Hi Julie:
It sounds like the problem may be with the fuel that you are using.
Make sure the tank is drained, rinsed, all stale fuel and contaminates removed, and fresh fuel used.
If you're going to be leaving the mower for extended periods between use, it's a good idea to fill the fuel tank with premium fuel.
I always fill the tank after mowing to minimize evaporation and condensation.
Hope this helps.

you are absolutely right on target. This is called 'hydro-locking, In fact many engines have been destroyed when a leaking fuel injector ,overnight, even partially fills a cylinder that is on compression stroke. With the higher cranking speeds today, It usually bends the connecting rod when the engine rotates 1/4 revolution s or more and 'hits' the in-compressible liquid.

In your case, simply remove the spark plug, and pull the rope a few times to blow out the gasoline and then add a teaspoon of oil in the cylinder, pull the rope a few times to re-lubricate the cylinder. When there is no liquid coming out, reinstall the spark plug and it should be good to go.

With carburetors, even a tiny speck of leaf or grass can cause the float valve to leak.

I need a little more information:-
Has the engine been apart recently?
Has the ignition timing been altered?
Have you checked for compression?
Have you got the correct fuel in the tank? (If the bike has been standing for some time, drain the fuel and put fresh fuel in it).
Assuming you have good compression, check that the spark is occurring at the correct time before Top Dead Centre (TDC).
After trying to start it, take the spark plug out and see if it is wet with fuel, or dry. this will show if fuel is getting into the cylinder.
Check for blockage in the air intake and condition of the filter. Check for blocked exhaust system. Off-road bikes can get very muddy!
If all these checks are fine, time to look at the carburettor. Water in the carburettor can be an issue, some carburettors have a fuel drain on the float chamber others you have to take the float bowl off. If you can, take the float bowl off, turn the fuel off first at the tank, and inspect the condition of the inside of the bowl. Clean out the bowl and blow through any air holes and jets. Check the float shuts off the fuel. Using minimum pressure lift the float up and turn the fuel back on. Fuel should flow past the float valve when you release the float slightly and shut off when the float is lifted again. If it does not shut off completely, you will need to remove the carburettor for a thorough cleaning. Hope this helps a little.

It is all in the carb. When you shoot ether into it it runs until it is burned off then the carb can't supply the engine with enough fuel to keep it running.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

The mower part is controlled by the solenoid on the carburator. It controls the idle and the fuel shut off and increase. Check the fuel bowl to make sure the wires are properly plugged in. If so, it may be time to put a new solenoid on the fuel bowl. You can also check the float in the fuel bowl. They normally have a plastic float in there. The kit you can buy to replace the gaskets and the float has a brass float in it as an upgraded part.

The ONLY way IN for fuel is the Float Valve, Now if petrol is coming out of the float bowl, then, the Valve must be faulty OR the Float mechanism, or spring, itself.

First thing I would check is the air filter. Then the belt that drives the wheels. Open up the belt area and clean. Last I would check the carb. Good luck...Lee

the float bowls are stiking open. you got dirt or something stuck in there. take carbs off and clean bowls.

Assuming that the normal tune up items have all been checked (valve adjustment, air filter, etc.) it sounds like it is running too lean. Check this by looking at the spark plug. Ideally, it should be light tan or brown in color. White indicates not enough fuel (too lean). Things that can cause this are: air leaks between the carburetor and engine, clogged fuel strainer in the petcock, float level too low, water or other sediments collected in the float bowl, modifications to the air filter box or exhaust system.
Drain the fuel from the float bowl into a clean container so you can see what has come out. If the fuel is free of moisture (water will clearly sit in the bottom of the container) and other junk, remove the float bowl (removing the carburetor from the bike first will make it much easier), check and adjust the float level.
If the above fails to solve the driveability problem, consider installing one size larger main jet in the carburetor, if available for your bike.

Hi , I think you need someone to remind you these engins are not made by god and they work by obeying three simple rules ,
1.Spark , Can you see a very good blue spark
2.compression,,can you feel strong compression ,
3.fuel , is the right amount of fuel getting in , is the air mixture good ,

Now try these things

Find the manual and PROPPER set the gap in the spark plug ,
clean and check the air filter ,
remove all fuel and replace with brand new,
check the fuel filter,even in the tank tap?
undo the screw at the carb bowl , can you see petrol leaking ,

If everything checks out then try this to get it started,,

spray "easystart" in the carb , bypassing the air filter ,
if it wants to start but cant for long then its a carb problem
check float hight , float needle,jets and pins ,too much air getting in

find someone thats good on motorbikes , They like me know all the tricks to get things to start ,