Possible 73 L48 Water Pump Casting No.'s

[Floyd B.]

My wife recently acquired her first Corvette and is starting to collect parts for her resto project. I was trying to help her find a water pump at Carlisle this weekend but encountered conflicting information as to what would be the correct casting number and configuration. The 2nd Edition 73/74 TIM&JG is now more than 15 years so when speaking with folks selling water pumps we ran into a lot of disagreement with the text in the water pump section on page 75. Several people disagreed with the third sentence which reads "The early 1973 style L48/L82 pump has a boss for a by-passport, but they are not drilled for the pump." We were told by one person that while "some" water pumps installed on 73 L48's may have had a pump with this configuration it would have been a very small number since these pumps were only cast for a few days in April of '72. Also, a few people disagreed that a 399207 was ever installed on any SB Corvette. We don't know what to believe.

We just need to know what the possible water pump casting numbers and configurations would be for a very early production (1-Aug-72) L48 w/ AC and 4spd.

Thanx

[Charles H.]

Re: Possible 73 L48 Water Pump Casting No.'s

Floyd-A new 73-74 JG has just come out, so maybe there is more detail in it. They just started shipping the new one last week. I'm in a hotel in Harrisburg right now. Eric Mortimer said there should be one in my mailbox when I get home.

[Michael W.]

Re: Possible 73 L48 Water Pump Casting No.'s

I don't think there's much doubt that the 330813 pump with a square headed pipe plug was used extensively in '73. They're usually easy to come by.

[Floyd B.]

Re: Possible 73 L48 Water Pump Casting No.'s

That's a bummer. We just paid $30 for the 2nd edition in Carlisle this weekend. Thanx for the heads up.

[Joe L.]

Re: Possible 73 L48 Water Pump Casting No.'s

My wife recently acquired her first Corvette and is starting to collect parts for her resto project. I was trying to help her find a water pump at Carlisle this weekend but encountered conflicting information as to what would be the correct casting number and configuration. The 2nd Edition 73/74 TIM&JG is now more than 15 years so when speaking with folks selling water pumps we ran into a lot of disagreement with the text in the water pump section on page 75. Several people disagreed with the third sentence which reads "The early 1973 style L48/L82 pump has a boss for a by-passport, but they are not drilled for the pump." We were told by one person that while "some" water pumps installed on 73 L48's may have had a pump with this configuration it would have been a very small number since these pumps were only cast for a few days in April of '72. Also, a few people disagreed that a 399207 was ever installed on any SB Corvette. We don't know what to believe.

We just need to know what the possible water pump casting numbers and configurations would be for a very early production (1-Aug-72) L48 w/ AC and 4spd.

Thanx

Floyd------


The casting number was 330813. Absolutely no doubt about that, at all.

Whether the upper bypass boss was drilled and tapped, there might be some doubt. I'd say the chances are about 99% it was drilled and tapped.

[Russ S.]

Re: Possible 73 L48 Water Pump Casting No.'s

Where is this info coming from? As far as I know there hasn't been any one working on a 73-74 3rd addition manual and the NCRS site doesn't list a third addition.

Floyd-A new 73-74 JG has just come out, so maybe there is more detail in it. They just started shipping the new one last week. I'm in a hotel in Harrisburg right now. Eric Mortimer said there should be one in my mailbox when I get home.

[Charles H.]

Re: Possible 73 L48 Water Pump Casting No.'s

Floyd-A new 73-74 JG has just come out, so maybe there is more detail in it. They just started shipping the new one last week. I'm in a hotel in Harrisburg right now. Eric Mortimer said there should be one in my mailbox when I get home.

Russ-I may have mis-understood Eric. He told me the JG that I ordered wasn't shipped to me because it was being reprinted. I took that to mean that a new one was coming out. So I most likely interpreted it wrong. They probably ran out of 2nd editions and were having more printed. I just got home from Carlisle and there is not a copy yet in my mailbox. Sorry for any confusion.Chuck

[Steve L.]

Re: Possible 73 L48 Water Pump Casting No.'s

My original water pump L48 from my 73 has the upper boss drilled, tapped and plugged with a square nut plug.

[Floyd B.]

Re: Possible 73 L48 Water Pump Casting No.'s

Steve,

What was the build date of your car? The TIM&JG states that only early cars may have had the undrilled/untapped pumps.

Thanx

[Steve L.]

Re: Possible 73 L48 Water Pump Casting No.'s

Steve,

What was the build date of your car? The TIM&JG states that only early cars may have had the undrilled/untapped pumps.

Thanx

Build date apr 10 1973 according to GM documentation. 420142

[Patrick H.]

Re: Possible 73 L48 Water Pump Casting No.'s

Steve,

What was the build date of your car? The TIM&JG states that only early cars may have had the undrilled/untapped pumps.

Thanx

Floyd, I think that the untapped pumps would be cars build in August of 1972 or so. I don't suspect that the untapped pumps went any longer than that, if at all.

[Joe L.]

Re: Possible 73 L48 Water Pump Casting No.'s

Floyd, I think that the untapped pumps would be cars build in August of 1972 or so. I don't suspect that the untapped pumps went any longer than that, if at all.

Patrick------


I agree.

[Floyd B.]

Re: Possible 73 L48 Water Pump Casting No.'s

Our car is #201 built on or about August 1, 1972. It is sometimes a real PITA finding parts for this car.

[Joe L.]

Re: Possible 73 L48 Water Pump Casting No.'s

Our car is #201 built on or about August 1, 1972. It is sometimes a real PITA finding parts for this car.

Floyd------


Find a 330813 waterpump dated within about a month prior to your engine's build date and that waterpump could easily have been installed on your car no matter what the bypass configuration is.

[Michael W.]

Re: Possible 73 L48 Water Pump Casting No.'s

Our car is #201 built on or about August 1, 1972. It is sometimes a real PITA finding parts for this car.

Like what?