Maybe this is the explanation you are looking for..
The reason why you can not switch gears with the engine running is because: as long as the clutch throwout (release) bearing is gone bad, the clutch pressure plate can not disengage the transmission input shaft from spinning. The bearing can get collapsed (become too short), sheared-down, or lock up when damaged. If the transmission input shaft rotation is not stopped, the brass synchronizer gears will not properly mesh together when 1-5 gear switching is attempted. If the synchros don't mesh, the gears dont engage. They would instead grind and possibly shear teeth off if forced.
If the bearing is good, (assuming all the hydraulic components are in good order) then when the pedal is depressed, the throw out bearing can do the job of taking up the required distance to push that pressure plate in far enough to disengage the clutch friction disk; effectively stopping or reducing rotational input from the engine. Once the transmission is "disconnected" from the engine's rotation, the synchronizer gears will properly mesh and allow your main 1-5 gear set to switch seamlessly.
The squealing "metal-on-metal" sound commonly heard from a bad clutch throw out bearing is caused by the steel ball/needle bearings within the bearing housing becoming stuck and no longer able to roll. The housing around the inner ball bearings becomes deformed under this enormous heat and friction of being stuck. Once the seized bearing assembly is projected inward toward the pressure plate, instead of gliding easily and supporting the pressure plate levers, it no longer spins freely and will just eat away at those spring lever fingers ( and SQUEEEAAL)
Smoke can also develop from this particular metal grinding or from the clutch friction disk being partially engaged against the pressure plate, or a combination of both. Let's hope the smoke isn't coming from the operator's ears! One must then keep their cool and extract the transmission for moderate servicing of the clutch system and maybe the axle output seals.
I hope this is informative and enlightening.
The reason why you can not switch gears with the engine running is because: as long as the clutch throwout (release) bearing is gone bad, the clutch pressure plate can not disengage the transmission input shaft from spinning. The bearing can get collapsed (become too short), sheared-down, or lock up when damaged. If the transmission input shaft rotation is not stopped, the brass synchronizer gears will not properly mesh together when 1-5 gear switching is attempted. If the synchros don't mesh, the gears dont engage. They would instead grind and possibly shear teeth off if forced.
If the bearing is good, (assuming all the hydraulic components are in good order) then when the pedal is depressed, the throw out bearing can do the job of taking up the required distance to push that pressure plate in far enough to disengage the clutch friction disk; effectively stopping or reducing rotational input from the engine. Once the transmission is "disconnected" from the engine's rotation, the synchronizer gears will properly mesh and allow your main 1-5 gear set to switch seamlessly.
The squealing "metal-on-metal" sound commonly heard from a bad clutch throw out bearing is caused by the steel ball/needle bearings within the bearing housing becoming stuck and no longer able to roll. The housing around the inner ball bearings becomes deformed under this enormous heat and friction of being stuck. Once the seized bearing assembly is projected inward toward the pressure plate, instead of gliding easily and supporting the pressure plate levers, it no longer spins freely and will just eat away at those spring lever fingers ( and SQUEEEAAL)
Smoke can also develop from this particular metal grinding or from the clutch friction disk being partially engaged against the pressure plate, or a combination of both. Let's hope the smoke isn't coming from the operator's ears! One must then keep their cool and extract the transmission for moderate servicing of the clutch system and maybe the axle output seals.
I hope this is informative and enlightening.
Comment