[NYGTO]

Hey guys, can someone please let me know what part number and proper date code I would need for a 1965 GTO late Mate build car? thanks of if anyone has one they would like to sell please p.m. me. Thanks again

['ol Pinion head]

No production dates til mid '67 production. Can go out and ck my supply of cores, know I have a few nice early cores with the late '63-64-65 design cast impeller.

[bill ryder]

I believe the casting # you are looking for is 9772716. No date code on housing. "Bill"!

[NYGTO]

That would be great. Thanks for reaching out.

[dhcarguy]

Here is the correct pump

[Jack P.]

Keep in mind a later and better impeller will fit on a early pump, looks correct and actually flows.

[60sstuff]

If you know the history of the engine maintenance and the water pump has never been changed, then have it rebuilt.

There are specialists in every component on these cars such as the water pump,

I pulled my OEM water pump off my 65 because it was leaking. Turns out the shaft was loose because of a worn bearing.

The gentleman that replace the bearing also sets the gap between the impeller and the single divider plate per factory.

GM designed it to work as intended and now my unit operates perfectly.

PS, I requested to leave the Original Paint on my pump to match back up with the timing cover.

Chris.

[GT182]

Make sure you get one that the impeller's curvature matches the curve of the inner divider plate. If it has a curvature. The matching up of them will keep the pump from having cavitation and not cooling as it should. Check the heating and Cooling Tech section.... the top Sticky thread - "Chalk up one more for the cast impeller." This is the one you want to read.... all of it. Or you can skip to about Page 51 or 52.

[John V.]

Be aware that the same pump body casting was used for the '63 4 cyl water pump.

Different pump assembly p/ns for the 4 cyl pump vs. V8 pump were assigned as seen in the MPC but the only way they are identified is by the p/n on the pump body casting.

Several years ago another member and I studied them and it seemed the 4 cyl version used an impeller with shorter fins. IIRC, there was an NOS pump being advertised at the time but was the 4 cyl version.

The one I had rebuilt had no codes that I could find. But I also have one that is stamped with nos. on the end of the pump shaft on the pulley end. It may or may not be a date code.

It shows a "W" and below that it shows "6406-1".

I was never able to find other examples with a similar shaft end stamping to derive any meaning from it. My sense was that the one that was stamped was an original shaft. But other than the fact it has no shaft stamping, I had no reason to suspect my other pump has anything but the original shaft installed in it.

I do agree with the other comments, no cast date code on the pump body as seen on later model pumps. Although I can't recall if I'd ever seen a Service Replacement '64-'65 Water Pump with the 9772716 pump body casting produced long after the '65 Model Year with a cast date code on the pump body perhaps. But if such a thing exists, it would not be an OE pump installed on a '64 or '65.

[NYGTO]

Thanks John, I got hit for 5 points at the GTOAA Nationals this past week for having a non oem replacement water pump (from approximately 40 years ago). Now I'll get this and several other small easy issues straightened out. It was my first GTOAA event, great time from start to finish.

[60sstuff]

Gary,

Find the correct 65 water pump and call -

Arthur Gould Rebuilders
Kings Park, NY
631-269-0093

I had them do mine in early 2015.

Extremely nice work!

Chris.

[bill ryder]

He did mine in 1990, Chris. Guess I'm showing my age!!!!!!!!!!!

"Bill"!

['ol Pinion head]

or... you save some $$$, receive a top quality rebuild, and get in on the next build session

[Slob4]

thanks to all foe the info reading the space between the fins and the divider!!!!
was having issues keeping the temp down so i took the water pump off today and wouldn't you know it - a 1/4 inch gap!!!! i followed the post and adjusted it down to .10 and the temp now does not go above 190 with all water !! thanks to all!!!!

[elefantrider]

Anyone on the west coast who can rebuild these?

Is a 326 pump the same as 389?

[Cardo]

The Dutchman is one of the best. Had him do mine. http://water-pump-rebuilders.com/contact.html

[elefantrider]

Thanks i wonder how much. They don’t list a price.
The rebuilt pumps from Ames are around $40.

[Cardo]

I want to say it was in the neighborhood of $120..... Just remember ya get what you pay for.

[elefantrider]

Found a pump laying around my shop. Has a strange impeller. Will it work?

[elefantrider]

Found another one. This one has a factory pn.