BigFellaQld
Cadet
- Joined
- Sep 3, 2002
- Messages
- 18
Re: no effect from 2 cylinders
I have never tried to physically test for crankseal leakage, I think that that is going to be difficult, due to the low crankcase pressures involved. One way to confirm the problem, though somewhat agricultural, is to remove the carbs, and hold a couple of the reeds open with matchsticks. Remove the stop switch lanyard, and crank the motor,while holding one hand over the carb mounting flange. If the seal is OK, the crankcase pressure will force your hand off the mounting flange. If the seal is crook, there will be minimal pressure there. Remember you are only testing 2 and3, so only hold the reeds open for those 2, otherwise you will get a false result. As I said, crude, but reasonably effective.<br />Another way, not quite so crude, is to index the flywheel, using a dial gauge, so that you have all four cylinders TDC marked on the flywheel. Leave the plugs out, and slowly rotate the flywheel by hand. As the indexed marks on the flywheel go past the TDC timing pointer, and the piston begins its downward movement in the bore, you should feel a resistance to your manual rotation of the flywheel. This resistance is caused by the piston compressing the fuel/air mix in the crankcase. You will find that 1 and 4 will feel quite different to 2 and 3, due to very little crankcase compression, but remember, the pressure is not great, so you really have to take a bit of notice. We have had a few of these fail over the years, when we were Suzuki dealers.<br /><br />Regards, Paul
I have never tried to physically test for crankseal leakage, I think that that is going to be difficult, due to the low crankcase pressures involved. One way to confirm the problem, though somewhat agricultural, is to remove the carbs, and hold a couple of the reeds open with matchsticks. Remove the stop switch lanyard, and crank the motor,while holding one hand over the carb mounting flange. If the seal is OK, the crankcase pressure will force your hand off the mounting flange. If the seal is crook, there will be minimal pressure there. Remember you are only testing 2 and3, so only hold the reeds open for those 2, otherwise you will get a false result. As I said, crude, but reasonably effective.<br />Another way, not quite so crude, is to index the flywheel, using a dial gauge, so that you have all four cylinders TDC marked on the flywheel. Leave the plugs out, and slowly rotate the flywheel by hand. As the indexed marks on the flywheel go past the TDC timing pointer, and the piston begins its downward movement in the bore, you should feel a resistance to your manual rotation of the flywheel. This resistance is caused by the piston compressing the fuel/air mix in the crankcase. You will find that 1 and 4 will feel quite different to 2 and 3, due to very little crankcase compression, but remember, the pressure is not great, so you really have to take a bit of notice. We have had a few of these fail over the years, when we were Suzuki dealers.<br /><br />Regards, Paul