is it neccessary to have a pilot bearing/bushing

[GMC500]

hi all

after inspecting my truck, I found that it only has a throw out bearing and no pilot bearing/bushing

is it neccessary to have a pilot bearing/bushing ?
and what is their advantages ?

truck is a 1986 GMC k15 with SM465

 

[1979jimmy350]

yes it supports the nose of the input shaft in the back of the crankshaft, are you sure that you do not have one that you just missed?

 

[Russell]

Yeah, I'd say it is! It keeps the shaft roating without any wobble, which would kill the input bearing pretty quickly...

 

[GMC500]

can you please post a pic of a pilot bearing/bushing installed in the crank

 

[pvfjr]

This is what the bushing looks like. The hole in it for the tranny input shaft is just a little less than 5/8". The hole that would be in the crank if there was no pilot bushing would be much larger, and you would have bad chatter issues with your clutch/tranny. If you're looking at it wrong, it might look like part of the machining of the crank. Hopefully you're mistaken. No bushing would be very bad.

 

[GMC500]

thanks

I will check it tomorrow before droping the engine