one more crankshaft seal question

hello,

i want to change the front crankshaft seal on my 94 rmw lt1. do i have to be concerned with
crankshaft postition, such as making sure it is at TDC, and not allowing the crankshaft
to rotate when the balancer and hub are removed? i have found references to doing
so on other forums, but it was not explained why. and i have read other descriptions
of doing the job in which neither is mentioned. i want to do it properly and know ahead of time
what is required. thanks for your help here.

anthony

It is because the keyway was removed on the crank nose!

yes, i have read about the fact that there is no keyway, but what difference does it make?
i think the key would allow you to put the hub back on in only one position on the crankshaft.
but why is that important? once the hub is on the crankshaft and bolted in place what's the
difference? it still spins with the crankshaft, right?

Indexing the front hub hasn't mattered since the timing marks were removed.

so does that mean i don't have to be concerned with anything? i just remove the balancer and the hub
and when i put them back on it doesn't matter what their orientation with the crankshaft position is as long as they are fastened properly to each other?

and i am wondering if the reference i saw to keeping the crankshaft from rotating was referring to stopping it from rotating as you try to bust loose the nut holding the hub on in the center?

okay, so i found the answer myself right in the FSM. it says that you should install
the hub and balancer in the position they were in when you removed them
because if you don't it can result in an "unbalanced engine".
also, definitely use a hub installer when putting it back on instead of just whacking
it back on with a hammer because pounding on it could damage the thrust bearing on the crankshaft,.
the thrust bearing handles any forward/backward motion of the crankshaft.

roadsurfer wrote:

... the FSM. it says that you should install the hub and balancer in the position they were in when you removed them because if you don't it can result in an "unbalanced engine"....

That rings a bell. I read that also in the FSM years ago. I think it's probably not important, but it's easy to mark the position, so do it.
On the 94 & 95 engines, the crank position info is recovered in the Optispark and sent to the PCM.
In 96, OBD-II made them put a crank sensor in the front cover. I don't know why, but I'll bet someone here DOES know.