Stihl 024 air leak

[PaulTem]

On 02/08/2012 at 19:40, spudulike said:

OK, understand the carb cleaner bit now, the inner metal insert holds the inner shape of the boot and the outer metal surround stops you flattening the rubber flange on the carb side of the boot.

 

One thing to check is that with both metal parts mentioned above in place, the rubber flange the carb is supposed to sit on is actually proud of the meta surround - this must happen so the carb compresses against it!

 

You could try making a paper washer and greasing both the rubber flange and the carb and then bush the carb home against it and then dissassemble to see if there is good connection between both parts.

 

The pressure test with the choke side of the carb blanked off and a bit of fairy liquid solution will show you where the leak is and would appear to be that the metal surround around the rubber carb boot is keeping the carb from sealing on the boot manifold.

 

The impulse line should push through the back plate and be held pretty firmly in place but sounds like this is sealing OK.

 

Many of the Chinese parts state Nikasil but there is no easy way of telling what you have. I aim for 150psi on a good running saw with 200-220PSI on my fully tuned ones:thumbup: The type of compression gauge does give a varied measurement.

 

End float on the crankshaft is moved by grabing hold of the flywheel or clutch and pushing and pulling the thing back and forth - you may have no play but sometimes this end float can cause air leaks in one position and not others.

 

Your description of taking the cylinder off is classic:lol:

 

Torque wrench - only on car bearings and cylinders etc. I use a small 6" tommy bar or T wrench as it allows me to crank the bolts down but not strip the thread. The nuts you are doing up are simple to do up, not technical - do them up with a deep socket using your fingers and then circa 1/2 turn until reasonably tight and the jobs a good un!

 

It sounds like you know where the air leak is, if the boot is in good condition, you must have some sort of mechanical interference stopping the carb pushing on the rubber flange.

Torque wrench?? when your knuckles turn white, it's tight enough Lol...

[spudulike]

Yup, Rowena are the go to carb specialists. Hugo is da man and very helpful.