C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

[Richard M.]

A local friend handed this used PS valve to me the other day as a gift for helping him rebuild his WCFB carburetor. The box was likely from a OTC part used to replace this. The box label is 7825636 but I'm unsure if that is what the actual part I have here is. Anything unique about this one as I'm not too familiar with these systems?

Thanks, Rich

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

A local friend handed this used PS valve to me the other day as a gift for helping him rebuild his WCFB carburetor. The box was likely from a OTC part used to replace this. The box label is 7825636 but I'm unsure if that is what the actual part I have here is. Anything unique about this one as I'm not too familiar with these systems?

Thanks, Rich

Rich-------


The valve looks to me like a GM #7816806 or GM #7819980. These were originally used on 1974-75 Corvettes. These valve really differ from the GM #7825636 only with respect to the hose guide. The hose guide on the valve pictured appears to me to be a GM #7817342 which was unique to the 1974-75 valves. The 7825636 was used in PRODUCTION for 1976-82 Corvettes and became SERVICE for all 63-75 Corvettes. The 7825636 used hose guide GM #7819613 which is configured slightly different than the 7817342. Original 1963-73 valves are not equipped with hose guides.

[Richard M.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Thank you Joe for the detailed reply.

If it is only the hose guide as a difference between what I pictured and a 7825636, could this be used as a valve for a 1963 to 1973 if the guide was simply removed? Are you saying the valve core itself didn't change from 1963 to 1975?

I'm certain it would need a rebuild as it probably wasn't working. Regardless I think I'll save it for a future need.

Rich

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Thank you Joe for the detailed reply.

If it is only the hose guide as a difference between what I pictured and a 7825636, could this be used as a valve for a 1963 to 1973 if the guide was simply removed? Are you saying the valve core itself didn't change from 1963 to 1975?

I'm certain it would need a rebuild as it probably wasn't working. Regardless I think I'll save it for a future need.

Rich

Rich------


The basic valve assembly (i.e. valve + adapter) did not change from 1963 to 1982. Of course, there might have been nuance differences over the years. However, I believe there were some internal differences over the years, the primary one being the valve spring. I think this changed about 1974 or 1975. I think valves equipped with the earlier spring are identified by a "C" stamped on the end cap with the later valves identified by an "X". I can't see the stamping on your valve as it seems to be covered by thick paint or grime.

[Richard M.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Rich------


The basic valve assembly (i.e. valve + adapter) did not change from 1963 to 1982. Of course, there might have been nuance differences over the years. However, I believe there were some internal differences over the years, the primary one being the valve spring. I think this changed about 1974 or 1975. I think valves equipped with the earlier spring are identified by a "C" stamped on the end cap with the later valves identified by an "X". I can't see the stamping on your valve as it seems to be covered by thick paint or grime.

Thanks Joe. I just went out and checked the end cap. After a good cleaning to bare metal, nothing at all is stamped on this one.
Rich

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Rich------


Attached are photos of an NOS GM #7817342 hose guide [not for sale] as used for 1974-75 Corvette power steering control valves.

[Mark M.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

What I've seen on many early original valves 63-69 is the X stamp cap and the two bolts holding it together are 12 point with a concave end. These don't use a shield / guide. Somewhere in the 70's the valves had a few changes. Often valves rebuilt with kits would leak again so many cars are missing originals as they would be replaced or exchanged. I've had good luck with these using a valve in good condition and rebuild with cssb inc. kits.

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

What I've seen on many early original valves 63-69 is the X stamp cap and the two bolts holding it together are 12 point with a concave end. These don't use a shield / guide. Somewhere in the 70's the valves had a few changes. Often valves rebuilt with kits would leak again so many cars are missing originals as they would be replaced or exchanged. I've had good luck with these using a valve in good condition and rebuild with cssb inc. kits.

Mark------


Yes, I had it reversed in my earlier response. Earlier Corvette power steering control valves had an "X" stamped on the end cap. Later valves had the "C". This denoted a change in the valve spring.

[Leif A.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Mark------


Yes, I had it reversed in my earlier response. Earlier Corvette power steering control valves had an "X" stamped on the end cap. Later valves had the "C". This denoted a change in the valve spring.

Joe,
What are you classifying as "later"?

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Joe,
What are you classifying as "later"?

Leif------

I don't know, for sure. I think it was sometime in the 1974-76 period.

[Leif A.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Leif------

I don't know, for sure. I think it was sometime in the 1974-76 period.

Thank you sir.

[Richard M.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Mark, Leif, Joe, Thanks for all of this info as I've now learned much about these valves.

Thanks for those photos Joe as it's always good to have references. I hope you didn't have to dig too deep to find them in the "Parts Department".

Rich

[Joe L.]

Re: C2 or C3 Power Steering Valve Identification - Possibly original 7825636 ?

Mark, Leif, Joe, Thanks for all of this info as I've now learned much about these valves.

Thanks for those photos Joe as it's always good to have references. I hope you didn't have to dig too deep to find them in the "Parts Department".

Rich

Rich------


Actually, I got a "freebie" on this photo. I took it several years ago and I happened to find it when I was looking for another part's photo. So, all the digging I had to do, I did awhile ago.