question crank shaft play??

B

BECERRASC

Registered User
hey guy i have 89 sc that is running like s#$( a ....... i did check everything plugs,wires,camsensor,cranck senor,dis,coil,supercharger ........ but i found was that the crank shaft has play i an push back and fowaward the crank shaft!!! any ............. idea of what should i do...... help please
 
BECERRASC said:
hey guy i have 89 sc that is running like s#$( a ....... i did check everything plugs,wires,camsensor,cranck senor,dis,coil,supercharger ........ but i found was that the crank shaft has play i an push back and fowaward the crank shaft!!! any ............. idea of what should i do...... help please
Click to expand...

How far can you push it? Normal end play is less than .008".
 
Are you sure it's the whole crank shaft that's moving not just the balancer? The balancers on these cars have a tendency to go bad.
 
more then 008 i think ..

because it causes to miss the crank sensor......


quickmustang > i have no balancer on it! .... and i moved pushing from the fly wheel ......... i foud this checking the balancer so i pulled i feel the play so i though the crank was broken in half so i when underneath and spin the fly wheel and spins free and the crank snout spins with the fly wheel so i know the crank isn't broke .... once i was under it was eazy to moved back and foward ......... any sugestions.......... other then a new engine...:(
 
Sounds like to me the thrust bearing on the crank is shot. Could very be looking at a complete rebuild as a result.
 
BECERRASC said:
because it causes to miss the crank sensor......


quickmustang > i have no balancer on it! .... and i moved pushing from the fly wheel ......... i foud this checking the balancer so i pulled i feel the play so i though the crank was broken in half so i when underneath and spin the fly wheel and spins free and the crank snout spins with the fly wheel so i know the crank isn't broke .... once i was under it was eazy to moved back and foward ......... any sugestions.......... other then a new engine...:(
Click to expand...

First thing you will want to do is verify roughly how much play there is. Use a dial indicator or a feeler gauge. I think it would probably take about .050" play to disengage the crank sensor. .008" is perceptible but probably wouldn't strike you as excessive just by moving the crank back and forth.

I've seen this before. It is possible that the main bearings are simply so bad that everything is loose in which case the motor (or at least the crank) may be shot, only way to find out is pull the pan. However, this problem can also be caused by the transmission which means that a new motor would suffer the same fate in short order. It is imperative that you figure out which problem you have.

An automatic transmission can balloon the converter from excessive rpm or load, or there can be something go wrong with the pump in the transmission that can put excessive pressure on the crank. Chances are if this is what has happened and the crank sensor is no longer working, the crank has pushed so far forward it has worn completely through the bearing material and is wearing into the block. Depending on how bad it is both the crank and block may be junk.

If the car is a 5spd, pressure is applied to the crank every time you press the clutch. On a 5spd this is normal but to have it wear like that implies a lack of oil in the motor, not a transmission problem. 5spds do not normally exhibit excessive thrust bearing wear even after 200K+ miles.
 
my crank also walks. and sometimes screws up my sensor. but i bought a new balancer and it came with a wider toothed plate for the balancer..
 
92redsupercoupe said:
my crank also walks. and sometimes screws up my sensor. but i bought a new balancer and it came with a wider toothed plate for the balancer..
Click to expand...

Chances are if this is what has happened and the crank sensor is no longer working, the crank has pushed so far forward it has worn completely through the bearing material and is wearing into the block. Depending on how bad it is both the crank and block may be junk.
Click to expand...

I wouldn't keep driving it if that is the case. The longer you drive it the more expensive the repair is going to be.
 
You must log in or register to reply here.
Back
Top