1971 water pump

[Paul Y.]

I wish to know the casting number of a 1971 350 water pump . Were they different on the LT-1? The serial # is --------6365. Thanks in advance.

[Edward J.]

Re: 1971 water pump

Paul, according to the 70/72 JM, Casting no. 3991399 was the 71 and early 72 350 small block, nothing is said about the LT1 engine, I would imagine there the same.

[Terry M.]

Re: 1971 water pump

Paul, according to the 70/72 JM, Casting no. 3991399 was the 71 and early 72 350 small block, nothing is said about the LT1 engine, I would imagine there the same.

Yep. The LT1 is just another small block.

[Ron G.]

Re: 1971 water pump

As Terry said, no difference. This configuaration was used thru early 72 and then the boss on top of the pump was seen on the majority of all 72's.

[Patrick H.]

Re: 1971 water pump

As Terry said, no difference. This configuaration was used thru early 72 and then the boss on top of the pump was seen on the majority of all 72's.

Ron,

I'll disagree with this one. From my research the 3991399 continues well into late 1972 MY cars. I suspect that it may have continued almost to the end of the year based on observation of original cars.

See here:

https://www.forums.ncrs.org/showthre...hlight=3991399

https://www.forums.ncrs.org/showthre...hlight=3991399

https://www.forums.ncrs.org/showthre...hlight=3991399

Patrick

[Ron G.]

Re: 1971 water pump

Pat,

After recveiving your reply I refered to some notes I had taken years ago, and even though my reply indicated early production, my notes I had from sometime ago indicated mid production and not early as I mentioned earlier. I can remember almost for certain that it was mid and not late, but I have been wrong before. As far as not agreeing with me, were not suppose to agree on everything which makes this discussion board interesting.

- Ronnie G.

[Patrick H.]

Re: 1971 water pump

Ron,

No problem.
Just want to make sure we keep it all straight.
I've got to catch you on an occasional detail, after all.

Patrick

[Paul Y.]

Re: 1971 water pump

Thanks for the information guys. I found the 399 in the parts I recieved with the car and I will have it rebuilt as the one on the car is an edelbrock aluminum after market. Thanks again. Paul

[Patrick H.]

Re: 1971 water pump

Paul,

What's the date on that pump?

Patrick

[Mike E.]

Re: 1971 water pump

Per your other threads Patrick, eBay seller. Saddlerockranch has both 330813 and 3991399 pumps for sale. He indicates the earliest 813 he has seen is April 14, and the latest 399 is March 9. Also interesting on both is the batch dates he indicates. One of my 399's is an additional date, but I don't have it anywhere near right now to tell you the date, other than mid-1970.
regards,
Mike

[Patrick H.]

Re: 1971 water pump

Per your other threads Patrick, eBay seller. Saddlerockranch has both 330813 and 3991399 pumps for sale. He indicates the earliest 813 he has seen is April 14, and the latest 399 is March 9. Also interesting on both is the batch dates he indicates. One of my 399's is an additional date, but I don't have it anywhere near right now to tell you the date, other than mid-1970.
regards,
Mike

Mike,

The 330813 that I posted last year was one of his. https://www.forums.ncrs.org/showthre...er-pump-330813
Actually, it was one that someone gave him for a rebuild, and I happened to talk wtih him at Bloomington and get the photos. Otherwise it would have been mine.


FYI my driver 71 had its original pump on it when I purchased the car. August 1970 casting on a late May 1971 motor. That's well outside the 6 month window but there is no doubt it had never been off the car previously.

Patrick

[Paul Y.]

Re: 1971 water pump

Patrick , it is 1/27/1 and the last "1" is different than the first "1". It has a minor left tail on the top. I'll submit a photo when I get it back from the rebuilder in the morning. Paul

Paul,

What's the date on that pump?

Patrick

[Patrick H.]

Re: 1971 water pump

Patrick , it is 1/27/1 and the last "1" is different than the first "1". It has a minor left tail on the top. I'll submit a photo when I get it back from the rebuilder in the morning. Paul

Thanks for the info.

[Paul Y.]

Re: 1971 water pump

You're welcome Dr.

[Joe L.]

Re: 1971 water pump

Per your other threads Patrick, eBay seller. Saddlerockranch has both 330813 and 3991399 pumps for sale. He indicates the earliest 813 he has seen is April 14, and the latest 399 is March 9. Also interesting on both is the batch dates he indicates. One of my 399's is an additional date, but I don't have it anywhere near right now to tell you the date, other than mid-1970.
regards,
Mike

Mike-----


The 3991399 pump had very limited application and I'm not surprised, at all, that it would have been cast in batches. Its use was limited to 1971-mid 72 Corvette small blocks and some 1971-mid 1972 MD and HD trucks. That's it; no other applications.

The 330813 had the same applications but it was used over a much longer period of time from mid-1972 through 1982 so it's more common.