C2 water pump casting varitations

[Steve S.]

Which casting would be the correct one for a 327/300 build date L82. I have 2 pumps with same casting number, 3782608, yet they differ in form. I have a rebuild kit and want to know which would be correct.

The original pump, the casting date can't be identified.


The other pump casting date is J2262(Oct 22 1962). Would this be correct for my motor.

[Steve S.]

Re: C2 water pump casting varitations

Original pump on motor.

[Steve S.]

Re: C2 water pump casting varitations

Oct. dated pump.

[Justin N.]

Re: C2 water pump

Steve,

My fourth Ed. 1967 Tech/Info Judging Guide says on page 85 under 'Base Engine' that "all engines use water pump casting number 3782608 without a bypass." Also the casting date code is obscured by the pulleys and shall NOT be judged. Not quite sure about the year of your car, but here's a shot of my recently rebuilt pump. Good Luck!

Justin #41362

[Joe L.]

Re: C2 water pump casting varitations

Steve----

The October-dated pump is a Tonawanda casting. This can be easily identified by the "T" casting mark and the reinforcing ribs on the driver's side of the pump. No Tonawanda-cast pumps were ever originally used on Corvettes. The other pump that you have pictured is a Saginaw-cast pump and would be correct as to configuration.

[Loren L.]

Re: C2 water pump casting varitations

I've been waiting for someone from the Judging team to jump in here and attempt to answer. Right now in my garage, I have FOUR different castings of 208 pumps, just as they came from the rebuilder.

[John H.]

Re: C2 water pump casting varitations

Loren -

Ribs on the driver's side = Tonawanda-cast pump, not correct.

No ribs anywhere = Saginaw-cast pump, correct.

[Steve S.]

Re: C2 water pump casting varitations

Thanks for all your help. looks like I'm rebuilding the Saginaw pump.

[Joe L.]

Re: C2 water pump casting varitations

Loren-----

Aside form the issue of the Tonawanda and Saginaw obvious differences, there were "umpteen" SLIGHT variations in the '608' casting over the many years of its use (1961 to 1970 in PRODUCTION). During the non-dated period (1961 to early 1964), I don't think that anyone has identified which, exact variation might be applicable to any dates within the period if, even, such a thing were possible. During the dated period (E1964 through 1970) any Saginaw pump casting with the correct date for the engine could have been the one originally used on that engine. In that case, the only way to know what the EXACT configuration of the pump used on that engine would be to have the known-original pump that was originally fitted to that engine.

I have the original '608' casting that was originally used on my 1969 300/350. It is dated "E 16 9" and was used on my August 14, 1969 assembled engine. I've looked at hundreds of '608' castings, many cast in 1969, and I've NEVER seen another one exactly like the one used on my engine.

There were MANY patterns used for the '608' waterpump casting since this was a WIDELY used casting for 61-68 small blocks. The production rate for this waterpump casting must have been very high. For some reason or another, some of the patterns, even those used during the same period of time, were slightly different. I don't understand why this was done as some of the differences necessitated differences in MACHINING for the finished waterpump housing. You would think that they would have wanted machining to be exactly the same for pumps produced during the same period. However, this was, apparently, not the case.