Joined May 2005
78 Posts | 0+
north island new zealand
nsman
maybe it would be a good idea to check the compression ratio detonation/preignition they border on each other they can be caused by lugging a motor, fuel octane rating to low for the compressin ratio wrong spark advance,lean mixture,wrong plug,hot spot in combustion chamber and even the kind of lubricant used and also piston to cylinder clearence which could cause scuffing that then leads to abnormal combustion.the dowel location was not questioned just wheather they were allowing the head to be tightened down it is quite easy to damage a dowel when pulling a motor apart is the spark plug showing detonation damage,has it turned a alloy colour from melting metal does the piston show signs of cracking preignition shows more as overheating, detonation shows more as a hammering effect on pistons, cylinders combustion chamber is the plug too white
maybe it would be a good idea to check the compression ratio detonation/preignition they border on each other they can be caused by lugging a motor, fuel octane rating to low for the compressin ratio wrong spark advance,lean mixture,wrong plug,hot spot in combustion chamber and even the kind of lubricant used and also piston to cylinder clearence which could cause scuffing that then leads to abnormal combustion.the dowel location was not questioned just wheather they were allowing the head to be tightened down it is quite easy to damage a dowel when pulling a motor apart is the spark plug showing detonation damage,has it turned a alloy colour from melting metal does the piston show signs of cracking preignition shows more as overheating, detonation shows more as a hammering effect on pistons, cylinders combustion chamber is the plug too white
