63 340HP idler pulley

[Joe L.]

Re: 63 340HP idler pulley

I have been looking for one with this end marking but it would appear 99% are clones and the 1% that are not, are asking Ebay prices for them.

Dennis------


This is a very old GM part number for the bearing assembly. This dates back to prior to 1963 so it's likely the one that was originally supplied as part of an original 1963 idler assembly. It might be good from an originality perspective to have an idler pulley assembly with this bearing. However, this bearing is the wear part of the idler pulley assembly. So, if you find one with this bearing, it might not be serviceable or, even if it is, it might not be for very long. Some things just die.

[Dennis B.]

Re: 63 340HP idler pulley

Dennis------


This is a very old GM part number for the bearing assembly. This dates back to prior to 1963 so it's likely the one that was originally supplied as part of an original 1963 idler assembly. It might be good from an originality perspective to have an idler pulley assembly with this bearing. However, this bearing is the wear part of the idler pulley assembly. So, if you find one with this bearing, it might not be serviceable or, even if it is, it might not be for very long. Some things just die.

Agreed...so if I have to take a repro....is it zinc or the darkened pulley for May 63?

[Dennis B.]

Re: 63 340HP idler pulley

Reading the NCRS Judging guide Rev 6 page 110 it says
"The bracket and pulley are painted semi-gloss black in most applications. The Pulley itself may have been a black phosphate finish. ................"
It goes on to say " Early 1963 idler assemblies have been observed with cadmium or zinc finish on the pulley itself ...............

So I am back to the dreaded "Early or Late". A May 24th car would be a late more so then an early in which case the black phosphate pulley may be the one?

https://www.corvettepacifica.com/products/15057/idler-pulley-assembly-with-special-high-performance-l63-65/

[Don H.]

Re: 63 340HP idler pulley

I suggest abiding by sentence one. If your car was pre-1963 production and you found a zinc or cad finish pulley, it would be a good choice.

[Bob R.]

Re: 63 340HP idler pulley

Dennis
A May car would have the black phosphate pulley. The black phosphate goes back much further than May my friends March 340 hp car has the original and it is black.

[Dennis B.]

Re: 63 340HP idler pulley

Thanks, thats what I will look for is the black phosphate unit