chevy v8 of the 70s thrust bearing load/time adequacy
chevy v8 of the 70s thrust bearing load/time adequacy
(OP)
A friend has a mostly original 1976 Corvette.
In a Motorcycle Safety Foundation course he took, their preference was when at a light stay in first gear and hold in the clutch.
I've seen a few cranks with deeply worn thrust faces of mixed makes.
The modern bearing manufacturers make a big deal about the improved profile they use today on thrust bearings to prevent wear.
Is he taking much of a chance of shortening the crank thrust bearing life (not the throw out bearings) holding depressing the clutch?
He will be replacing the original clutch with a centerforce unit in a few weeks, and I will lend them my dial indicator to check existing crank endplay, among other things.
In a Motorcycle Safety Foundation course he took, their preference was when at a light stay in first gear and hold in the clutch.
I've seen a few cranks with deeply worn thrust faces of mixed makes.
The modern bearing manufacturers make a big deal about the improved profile they use today on thrust bearings to prevent wear.
Is he taking much of a chance of shortening the crank thrust bearing life (not the throw out bearings) holding depressing the clutch?
He will be replacing the original clutch with a centerforce unit in a few weeks, and I will lend them my dial indicator to check existing crank endplay, among other things.





RE: chevy v8 of the 70s thrust bearing load/time adequacy
The cyclist must be able to depart _immediately_ when the light changes, or when the car behind starts to move, for personal safety. The clutch reaction in a motorcycle is taken by bearings in the transmission, not engine bearings.
The Chevy driver probably wants to save his plain thrust bearing by leaving the box in neutral until the light changes. His incentives are different, since his personal safety is at less relative risk at a light.
Mike Halloran
Pembroke Pines, FL, USA
RE: chevy v8 of the 70s thrust bearing load/time adequacy
This not only saves crank end thrust bearings but also saves clutch face wear.
Regards
Pat
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RE: chevy v8 of the 70s thrust bearing load/time adequacy
RE: chevy v8 of the 70s thrust bearing load/time adequacy
RE: chevy v8 of the 70s thrust bearing load/time adequacy
It may not be particularly large, amounting to the converter internal pressure times the area of the seal between converter and transmission nose.
Mike Halloran
Pembroke Pines, FL, USA
RE: chevy v8 of the 70s thrust bearing load/time adequacy
I am an early Hydramatic fan, Dynaflow, not so much, though it too is a very interesting engineering exercise. I recall a report that the Dynaflow equipped Old's had slightly better 0-60 acceleration than the Hydramatics, probably because they allowed the engine to rev a little higher on average during the accel. Fuel economy, fahgettit!
I forgot what I was going to say
RE: chevy v8 of the 70s thrust bearing load/time adequacy
Of course you needed an anchor to stop the old Dynaflows- very little engine breaking. Brake shoes lasted about 6 mo /10,000; compared to hydro cars which could get a whole year/ 20,000 miles. Of course then you were past needing plugs and points and probably a fuel or water pump.I invented a fuel pump in nowhere Wyoming one afternoon (or I would still be there).
You kids today are spoiled with modern cars.
RE: chevy v8 of the 70s thrust bearing load/time adequacy
Palpable engine braking as well as decel downshifts were certainly distinguishing features of the original Hydramatic.
I forgot what I was going to say
RE: chevy v8 of the 70s thrust bearing load/time adequacy
Benta.
RE: chevy v8 of the 70s thrust bearing load/time adequacy
Franz
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RE: chevy v8 of the 70s thrust bearing load/time adequacy
That said, aside from the excessive wear on the thrust bearing, throwout bearings aren't meant to handle the high duty cycle involved.
THAT said, it is also a safety concern. If rearended, the driver's foot can slip off of the clutch and the car can lurch into cross traffic.