Husqvarna k760

[Adal]

Hello all

i hope you can help me Please. I have a husqvarna k760 that I have been trying to fix. At first i renewed carburettor diaphragm and gaskets still no luck I found that the compression was very low and the piston and cylinder had deep marks on the sides of the piston and walls of the cylinder so I renewed with new piston and cylinder head and gasket still will not start. Then I renewed the magneto and spark plug still no start I have had the carb in bits I have used carb cleaner on it still will not start. I have petrol from the tank to the primer. But if you take out the spark plug it is dry so is the cylinder. If I put petrol in the cylinder it will start.I bought a carburettor off e bay second hand sill no luck. I was told to take the carburettor to bits and remove the high and low needles then clean it with carb cleaner then blast it out with air but you need a tool to remove them that I have not got I just do not know what to do next at the moment I have a cutter on hire with the parts to fix this and hire is getting bad I hope some one can help me Please Alan

[adw]

The K760 is very bullet proof so there has to be some fairly obvious wrong with it, so to start, look at where the alloy inlet manifold connects to the back of the cylinder, it hooks under a plate on the back of the cylinder, there should be no gaps here it should fit and seal firmly on the cylinder, next make sure the impulse hose is connected, next have you fitted a genuine metering diaphragm? the after market ones do not have the additional hole to feed the compensator, next the rubber gasket between carb and air filter box, is it in good condition and aligned correctly? next did you fit the piston the right way round? this is very important as this saw has a ex torque cylinder, next if this is an after market cylinder make sure you have the correct inlet manifold because the cylinder ports were widened on the latter cylinder, carb settings are L 11/4  H1 3/4

[Adal]

Hello adw

how do you test to see if there is a gap between the manifold and the back of the cylinder, the impulse tube from tank to intake is fitted right, I will get a new rubber gasket for the air filter box, yes the piston was fitted right way the arrow faces the exhaust, the bore of the cylinder is 51 mm, the intake ports is 27 mm from centre to centre the cutter is pre 2013) thank you for your time helping me I will keep you posted if that is ok

Alan

[adw]

You can look from the r/h side between the covers, you will see the the back of the cylinder, you should not see a gap where the manifold is not fitting tight to the cylinder, just measure the distance between x torq ports on the original cylinder and compare with the new one, the impulse tube runs from the top of the carb to a connection on the inlet manifold. 

[adw]

Sorry I got the carb settings round the wrong way, L = 1 3/4 and H = 1 1/4 sorry I had a moment.

I can take some pictures of the cylinder and manifold if it helps.

[Adal]

 

If you do not mind photos will help. yes the tube that comes from the top of the carb to the inlet manifold is on right