PS Pulley with a key way

[Geoff C.]

I CRS. Does any C2 or C3 Corvette PS pulley use a key way? I thought none.

Geoffrey Coenen

[Joe L.]

Re: PS Pulley with a key way

Geoffrey-----

No 63-82 Corvette power steering pulley uses a key way. The 1963-74 pullies are designed with a tapered shaft hole for use with the tapered shaft pumps used during those years. These pullies are all retained by a special lock-nut which threads onto the end of the shaft. 1975-82 pulley has a straight shaft hole and there is on provision for a retaining nut on the shaft. This pulley uses a heavier interference fit for retention.

There were only 6 pullies ever used for all 1963-82 Corvettes with power steering. Those pullies are as follows:

GM #3770509-----stamped steel, single groove, "pancake" style; used GENERALLY for many 63-74 small block applications with base engine and/or C-60; discontinued April, 1997

GM #3834720-----cast iron, single groove, "drop-down" style; used GENERALLY for many 63-74 applications with HP and SHP small blocks without C-60; discontinued;

GM #3868892-----stamped steel, single groove, "pancake style"; used only for 65-66 L-79 with C-60; discontinued January, 1976;

GM #3878245-----cast iron, two groove; used for all 1965-74 big block applications; discontinued;

GM #346289------stamped steel, "pancake style", single groove; used for all 1975-79 Corvettes; discontinued September, 1981;

GM #14023175-----stamped steel; "pancake style", single groove; used for all 1980-82 Corvettes; functionally identical to the 346289 and replaced that pulley for 75-79 SERVICE in September, 1981. You can still get this one.

[Geoff C.]

Thanks Joe *NM*

[Paul Reynolds]

Re: PS Pulley with a key way

OK, So here's my question.... On the Power Steering "Kits" that are available from many sources, there is a key and the "special" locknut. I'm running a 3834720 cast iron pulley which also has a keyway. The shaft of the pump is not tapered and has a keyway. Before I changed pulley configurations, I was running a 3770509 pulley which also had a keyway.
Was something redesigned along the way?

[Joe L.]

Re: PS Pulley with a key way

Paul-----

Yes, I blew it on this one. The 63-74 pullies all DO use a key way. However, the shaft end IS tapered also. It's a slight taper, but it is tapered.

[Joe L.]

Re: PS Pulley with a key way

Geoffrey-----

See my latest response to Paul. I blew it on this one. The 63-74 pullies DO use a keyway. When I responded I had this vague recollection that maybe the early ones did, but the more I thought about it, the more I convinced myself that they didn't. I should have gone out and checked the parts. I have NOS examples of all the pullies, many NOS examples of the pump shafts and, even, many NOS examples of the 63-74 pumps [none for sale]. So, I had plenty of material to research this one. It's just getting so hard to get at a lot of this stuff even though I have it in bins by group number. Sorry for the mis-information and confusion I created. I ABSOLUTELY HATE to make a mistake like this. It'll bother me all day.

[Paul Reynolds]

Re: PS Pulley with a key way

No problem Joe. With all the different part numbers you have cataloged, I'd be cross-eyed. Your contribution to this forum and hobby is priceless. We all have a "moment" from time to time. Try not to let it bother you too long.

[Geoff C.]

[Patrick H.]

Re: I CRS

Very, very good.

You're getting there. I'm sure we will have to have another liquid therapy session in Carlisle, but you are making excellent progress.

PH MD

[Jack H.]

Amen! *NM*