Water Pump question....
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 1,133
Likes: 2
From: Corona CA
Water Pump question....
I was wondering.....is there any way to determine if a water pump is original....if so is there some point in keeping an original unit?
I have owned my car for a long time and it was a pretty original driver when I bought it...and while I am not a stickler for originality I do try to not make any changes to the car that can't be undone. I also try to keep any original parts that I remove.
Well I am moving and going through all my old parts. I have from time to time changed out the water pump and I have several, one that might be the original. If there is some way to identify it from the rest I will hang on to it. Maybe get it rebuilt and sell with the car or sell to someone that needs a period replacement. If they is no way to ID it or there is no big reason to keep it then I will just get rid of the whole collection.
Thanks
Darren
P.S. this is a 1965 365hp car
I have owned my car for a long time and it was a pretty original driver when I bought it...and while I am not a stickler for originality I do try to not make any changes to the car that can't be undone. I also try to keep any original parts that I remove.
Well I am moving and going through all my old parts. I have from time to time changed out the water pump and I have several, one that might be the original. If there is some way to identify it from the rest I will hang on to it. Maybe get it rebuilt and sell with the car or sell to someone that needs a period replacement. If they is no way to ID it or there is no big reason to keep it then I will just get rid of the whole collection.
Thanks
Darren
P.S. this is a 1965 365hp car
Le Mans Master
Joined: Nov 2000
Posts: 7,246
Likes: 21
From: Going too fast over the hill. Iowa
water pump housings have a date code cast into them. IMO the date should precede the engine assembly date by a month or so. If you are having the car judged they will allow more than that - probably up to 6 months
Melting Slicks
Joined: May 2007
Posts: 3,461
Likes: 18
From: cooper city florida
The correct pump for your car is the 326 pump. It has the 1/2 inch bypass which is corvette specific,and fairly rare. There are thousands of 326 pumps out there but they were made for trucks and have a 3/4 inch bypass,and they need an adapter to use on a corvette. They didn't start to date code that pump until Nov 1965. Soooooooooo, if you have a non dated 326 pump,with the 1/2" bypass,you have the correct,and very possibly the original water pump. By the way the 1/2 inch is actually the inside diameter of the hose opening. I believe if you measure across the bypass hole in the top of the pump,it will measure 3/4",but that is the corvette pump.
Race Director
Joined: Jan 2007
Posts: 13,671
Likes: 14
From: Down on the bayou in south Louisiana
St. Jude Donor '10
The correct pump for your car is the 326 pump. It has the 1/2 inch bypass which is corvette specific,and fairly rare. There are thousands of 326 pumps out there but they were made for trucks and have a 3/4 inch bypass,and they need an adapter to use on a corvette. They didn't start to date code that pump until Nov 1965. Soooooooooo, if you have a non dated 326 pump,with the 1/2" bypass,you have the correct,and very possibly the original water pump. By the way the 1/2 inch is actually the inside diameter of the hose opening. I believe if you measure across the bypass hole in the top of the pump,it will measure 3/4",but that is the corvette pump.
Le Mans Master
Joined: Jul 2003
Posts: 6,808
Likes: 24
From: Westport CT
The correct pump for your car is the 326 pump. It has the 1/2 inch bypass which is corvette specific,and fairly rare. There are thousands of 326 pumps out there but they were made for trucks and have a 3/4 inch bypass,and they need an adapter to use on a corvette. They didn't start to date code that pump until Nov 1965. Soooooooooo, if you have a non dated 326 pump,with the 1/2" bypass,you have the correct,and very possibly the original water pump. By the way the 1/2 inch is actually the inside diameter of the hose opening. I believe if you measure across the bypass hole in the top of the pump,it will measure 3/4",but that is the corvette pump.
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
The full part number is 3859326 and I just wanted to add that I believe the front pulley mount should have only 4 holes and NOT the 8 that some reflect (other experts can chime in to correct if I am wrong)The question I have is I notice that some have GM1, GM2,......GM8 etc near the part number 3859326. Is there some significance to which would be correct? I assume that the later GMx numbers were either over the counter replacements OR just came later...??
Are the GM1's for '63 GM2's for '64 etc...?
Thanks
Thread Starter
Burning Brakes
Joined: Aug 2005
Posts: 1,133
Likes: 2
From: Corona CA
Okay, thanks for the information.
I will sort thru the pumps I have and see if any might be original or suitable as original replacements. My car is a very early 65, so probably as mentioned it won't have an actual date stamp. But if I have any extras that might be stamped a bit too late for my car or earlier unstamped I will hang on to them maybe offer them up as a pay it forward.
Darren
I will sort thru the pumps I have and see if any might be original or suitable as original replacements. My car is a very early 65, so probably as mentioned it won't have an actual date stamp. But if I have any extras that might be stamped a bit too late for my car or earlier unstamped I will hang on to them maybe offer them up as a pay it forward.
Darren
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
The question I have is I notice that some have GM1, GM2,......GM8 etc near the part number 3859326. Is there some significance to which would be correct? I assume that the later GMx numbers were either over the counter replacements OR just came later...??
Are the GM1's for '63 GM2's for '64 etc...?
Thanks
Are the GM1's for '63 GM2's for '64 etc...?
Thanks
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