Suzuki 75 running on only 2 cylinders

" I have an '87 Suzuki 75H

" I have an '87 Suzuki 75Hp triple. It's only running on 2 cylinders. I changed the plugs,cables spark is there. Ran compression test on all 3 cylinders (not more then 12 psi difference between cyl. The motor sat for about 1.5 year without really running. Could anyone give me pointers on what to look for next "

" John,

I would advise you

" John,

I would advise you to check the carburettor that feeds the cylinder that is not working. While you have the carb off, take a look at the reed valves. You should be able to determine if any are broken or badly bent by looking through the carb mounting flange.

More than likely, if there is a carb problem, it will be that the main jet is clogged. This screws into the carb body from the bottom. It is clearly visible when you remove the float bowl.

Check the valve which is operated by the float. It should move freely and must seal when closed.

The idle jet screws into the body from the top, just about center. Remove and clean it, and clear the channel between the float chamber and the idle jet.

You will notice an aluminum plug just aft of the idle jet. It pays to remove it by carefully drilling a 1/8 inch hole through it. Then you can insert a punch or similar device and pry the plug off. Clean everything in there.

You should also try turning the flywheel in a clockwise direction by hand and see if you feel a noticeable difference in the compression of the cylinders. Sometimes, a compression test will not give you an accurate picture of the condition of the pistons, rings, and cylinder walls. If you do not feel any resistance when turning the flywheel by hand for a given piston, then you can bet that piston or cyulinder needs work.

Tony "