Author Topic: 67 z/28 waterpump casting number  (Read 1742 times)

Ron C.

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67 z/28 waterpump casting number
« on: November 30, 2009, 01:06:16 AM »
The casting number that is on the 302 waterpump should be 3858326 or 3998207, is that correct? Thats what in jerrys book but I have seen more 3859326 pumps. I was just wondering which would be correct for mid year 67 Z28s.
67Z/28,67RSZ/28,71SS454CHEVELLE.

Jon Mello

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Re: 67 z/28 waterpump casting number
« Reply #1 on: November 30, 2009, 03:33:21 AM »
Ron,

The 326 pump is the one to use.

-Jon
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jonboy1216

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Re: 67 z/28 waterpump casting number
« Reply #2 on: December 01, 2009, 09:31:54 PM »
which one is correct for a april built 68 z28?


JohnZ

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Re: 67 z/28 waterpump casting number
« Reply #4 on: December 02, 2009, 03:35:19 PM »
which one is correct for a april built 68 z28?

3859326 like this one...

http://cgi.ebay.com/ebaymotors/67-68-69-CAMARO-WATER-PUMP-FOR-A-302-Z28_W0QQitemZ250539757171QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item3a55554e73

Paul


That photo very cleverly doesn't show the most important part of the 326 water pump - the tapped hole in the boss on top for the bypass fitting. Original passenger car 326's had a 1/2" NPT hole for the fitting, but the overwhelming majority of 326 pumps were made for truck applications, and used a larger 3/4" NPT hole. Commercial rebuilders convert most small-hole 326 pumps to 3/4" NPT (since the biggest volume for them is for trucks, not cars), which ruins their originality value for cars, since you have to use a reducer bushing, which results in a deduction in judging. Beware any auction for a 326 pump that doesn't show the size of the bypass hole (especially when the auctiion says "no returns accepted" like that one does).
'69 Z/28
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1968RSZ28

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Re: 67 z/28 waterpump casting number
« Reply #5 on: December 02, 2009, 06:05:52 PM »
which one is correct for a april built 68 z28?

3859326 like this one...

http://cgi.ebay.com/ebaymotors/67-68-69-CAMARO-WATER-PUMP-FOR-A-302-Z28_W0QQitemZ250539757171QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item3a55554e73

Paul


That photo very cleverly doesn't show the most important part of the 326 water pump - the tapped hole in the boss on top for the bypass fitting. Original passenger car 326's had a 1/2" NPT hole for the fitting, but the overwhelming majority of 326 pumps were made for truck applications, and used a larger 3/4" NPT hole. Commercial rebuilders convert most small-hole 326 pumps to 3/4" NPT (since the biggest volume for them is for trucks, not cars), which ruins their originality value for cars, since you have to use a reducer bushing, which results in a deduction in judging. Beware any auction for a 326 pump that doesn't show the size of the bypass hole (especially when the auctiion says "no returns accepted" like that one does).

John -

Jerry MacNeish's "The Definitive 1967-1968 Camaro Z/28 Fact Book" states that the water pump installed on all 1967 and 1968 Z/28 engines had two slightly different designs; one with a 1/2" NPT bybass hole and one with a 3/4" NPT bypass hole.

Paul

1968RSZ28

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Re: 67 z/28 waterpump casting number
« Reply #6 on: December 03, 2009, 02:21:56 AM »
That photo very cleverly doesn't show the most important part of the 326 water pump - the tapped hole in the boss on top for the bypass fitting.

I emailed the seller about the bypass hole on this water pump.  Here is his response...

Hi,
Yes it does have the bypass hole, it is 3/4 in.
Thanks

- ziggy-777


Paul