Better explaination
That was a very good explanition and very helpful.
When you mention this "jerk" or load applied to a drive clutch how does this relate to engine mounts. Is it the load itself that pulls the crank out of true and (or) the block being pulled out of position and placing abnormal thrust and side presure on the PTO bearings.
I guess a better way to ask that, do the aftermarket mounts prevent crank distortion under load ?
Thanks this has been a great post all the way around
I was refering to two different types of Jerk on the crank.
#1 - a straight " jerk " back on the drive clutch applied by the driven, When a fast spinning track hooks or grabs something very hard.
#2 - A slide hammer type " jerk " applied by the drive clutch at engagement, when the moveable sheave comes in contact with the belt it is getting is leverage from the stationary sheave wheich is hooked to the crank.
One I did't mention, Blowing a belt at full throttle unloads the motor so fast that the crank actually bows and many times comes in contact with the case ( Few of you may have seen this,) Aluminum strips on the center seal hub that has been shmeared. after a belt has been blowen at high speed most cranks are at that point knocked out of tru to some degree. ( a good tight case will sometimes re-tru it to a point ) normally not as good as it once was.
As for the motor mounts, The more torque stops you add to your motor, the more energy you drive into the crankshaft, and the less energy that goes into the motor mounts.
The is why I hate torque ( arms ) and prefer torque ( stops ) Stops should be installed with clearance .060 to .100 thou and NEVER be up against the motor ( unless ) your a drag racer and winning comes first and the crank caomes second.
Imagin, when there are no torque arms or stops............ all the motor mounts absorb some of this energy, torque stops and arms can really screw things up if not installed with some thought of what you want out of them.