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I removed the fitting from the replacement H2O pump that was on my engine. It has the "CP" logo in diamonds and is 1" across the top diagonally. I thought it was original and would fit into the original ...326 pump I'm installing, but the threaded end is too large. It goes in about 1/4 turn. The JM calls for a 5/8" opening in the H2O pump. How exactly is that measured? Hopefully the fitting is the problem and not the pump.
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Re: '66 L79 H2O pump bypass fitting
Rob,
Did you chase (clean)the threads on both the water pump and the "L" fitting? I just finished installing a rebuilt 326 water pump on my '65 L79 using the original fitting with the diamond pattern. I had to clean up the threaded portion of the water pump and "L" fitting before I could get it to screw in correctly. It was the same as you are describing and would not screw in more than 1/4" until the treads were cleaned.
By the way, I'm curious were did you get the 326 water pump??? I have an interesting story about a vendor on EBay trying to sell counterfit GM 326 water pumps as originals. They were cast in Turkey and are not correct.
Regards,
James West -
Re: '66 L79 H2O pump bypass fitting
I'll try cleaning the threads...where do I get a tap that large? I got the pump from the guy at Chicago Corvette that sells the carbs. I believe his name is Al. It's dated correct for my car and has all the correct physical characteristics, including 66 cast on the back.Comment
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Re: '66 L79 H2O pump bypass fitting
Rob,
I used one from here in the machine shop at work. I just went out to the tool room at break time and picked a 1/2" -14 NPT pipe tap which is what I used to clean the threads out on my water pump. Send me an email with you shipping address and I send you the tap and some cutting oil today via USPS Priority Mail. When you are done, just send it back to me.
Thanks,
James WestComment
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Counterfeit?
That's a harsh term, James... It means you have specific knowledge of an intentional wrong doing (legal definition). Do you?
I know there's a source for 'bad' reproduction(s) of the '326 water pump casting that I've chatted about off-board with Joe Lucia and John Hinckley. A friend sent one to me to have it rebuilt and it has 'little' resemblence to the real McCoy part made by GM back in the 60's...
There's an obvious surface texture disturbance in the front area where the casting insert would have been placed to effect date coding. The size and font of the GM casting number differ markedly from original pumps from the era. The upper boss dimensions are also quite dissimilar from orignal pumps and the casting source (large 'S' on the back side) is missing. There are other differences too.
But, in doing some follow-up research, I found a picture of the same, poor replica, of this pump on Zip Products web site. There, it was 'featured' as a new GM Licensed Reproduction part...
That would suggest it's NOT a 'counterfeit' part, simply a poor quality, reproduction. That's a problem with GM's reproduction program...they license parts for reproduction but stand at arm's length from their licensee's and let them churn out products that may differ markedly from the original(s) in terms of form, fit, function.
On the fit of the bypass elbow, you've given good advice to chase the threads! Several of the catalogs (plus some NCRS literature) refer to the medium size upper bypass hole as being 5/8-inch when it's actually drilled and tapped for 1/2-inch NPT. The only saving grace is there's no such thing as a 5/8-inch NPT die/tap set, but many confuse the correct size based on these mis-statements!
In general, there were three hole sizes used: 3/8-inch, 1/2-inch, and 3/4-inch with the smallest used on some '493 castings back in the late 50's. The most common is the large 3/4-inch hole commonly used in truck applications. The medium, 1/2-inch hole, was pretty much restricted to Corvette and HP Camaro engine applications.Comment
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Re: Counterfeit?
Jack,
I made the mistake of buying one of these bad water pumps off of EBay from a parts vendor in Ohio. What I got was not even close and in my opinion would have restricted water flow based on the too small of passages in the casting and the oustide of the casting was ground off where they are typically not. I spoke with a well known water pump rebuilder in in Oklahoma and sent him pictures of it. He said that it was cast in Turkey and had had the same bad experience for the same parts vendor in Ohio. The term I used to descibe the water pump is what he told me. I had a hell of a time getting my money back, but finally did less the shipping costs. I have since found a correct, used 326 pump and had it rebuilt and installed it my '65.
I did contacted GM, told them the details, sent them pictures and received a nice response which directed me to send the information to the legal firm that handles their product licensing. I haven't heard any news back from them.
Are you at the National meet?
JamesComment
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Re: Counterfeit?
Nope, I'm not at the National... Spent my $$$ going to Amsterdam & LeMans this year.
The fact that you haven't heard back could indicate I'm right (the '326 water pump actually IS manufactured under license & it's simply a 'poor' quality reproduction)... Let's see if this works: a link to the Zip Products web site showing their 'new' (not remanufactured) water pump.
Look very closely at the LH front side of the pump and you can see the 'distortion' in the area where the cast date insert would normally be found. The one I held in my hands was NOT 'ground down', the area where the normal casting insert went was rather clumsily 'plugged' in the mold.
It could well be we're talking about the same item. Who knows, maybe it IS built under GM license, off shore... If so, the preferred terminology would be 'poor reproduction' rather than 'counterfeit'....
326 Water Pump
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Re: Counterfeit?
Jack,
The picture you posted did not come through; please send it to me via email so that I can look at it.
I too opted to not attend the National meet, just returned Sunday from a week’s vacation with the family, I'm tapped out. We are starting to schedule our 2008 projects here at work this week, I made it known to my boss that I would not be available the first week in May so that I can attend the regional meet in Denver, looking forward to assisting your club in any way I can. Any news on where it will be held? Our chapter judging meet is a month from today, and so far I have four midyear cars that have sent in judging registration paperwork, now all I need to do is see if I have enough qualified judges to judge all four cars in timely manner on that day. I guess it's better than not getting any cars at all, I hope to do all the cars, all but one are coming from out of state locations.
Regards,
JamesComment
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Re: Counterfeit?
Hum, my prior post works for me when I click on the highlighted hypertext (326 Water Pump) that's below the picture icon...Comment
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Re: Counterfeit?
Jack,
Somethings fishy I don't get a picture but see the broken picture icon. The link as you said works fine. Here's what I think you wanted.
Kevin
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Re: '66 L79 H2O pump bypass fitting
James, would you mind posting the URL of the person selling the less than original water pumps? I would hate to reinvent the wheel on this. Off line is ok too.
GaryComment
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Re: '66 L79 H2O pump bypass fitting
The seller is Restoration Auto Parts and here's a link to a current auction for the part James mentioned. You'll note their description claims the pump to have been commerically rebuilt, but I think there's an ethics issue here as this appears to be the same part Zip Products lists on their web site as 'new' and a reproduction...
eBay 326 Water PumpComment
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Note...
If the two pumps actually are the same, then it's a question of restoration economics. Zip offers two versions of the '326 pump in their catalog.
One is described as a rebuilt original and priced at $179.50. The other is said to be 'new' and is lower in price at $139.95. That's telling you something about the quality/judgeability of their 'new' pump now, isn't it?
But, in Zip's defense, there IS a $40 difference between the two items and what I observed to differ on the reproduction pump I inspected should result in a 40% deduction on originality (violates Configuration and Date components of originality but has the same Finish, Installation and Completeness parameters).
Plus, they don't describe their rebuilt '326 pump very well. Is it dated or not? Is the upper boss drilled & tapped at 3/4-inch NPT for 'truck' vs. Corvette/Camaro applications? So, the restorer is faced with specifically asking what he/she gets for their money with Zip's rebuilt '326 pump AND looking in the mirror to decide what it's worth for the originality deduction(s) that the 'new' version of the pump would probably take on the judging field.
BTW, I suspect the situation isn't just limited to the '326 water pump. The Zip catalog also lists the rather rare, 1961-63E '609 water pump in 'new' condition. The catalog picture portrays it as the same physical casting as their new '326 with, apparently, a different insert in the mold for the different casting number.
But, any savvy judge will QUICKLY detect the configuration difference in the pump housing's upper boss. Original '609 pumps had barely enough 'meat' on the upper boss to support a 1/2-inch NPT bypass elbow let alone the larger 3/4-inch NPT hole for a 'truck' bypass. That's essentially the difference between the '609, '175 and '326 water pump housings. The upper boss 'grew' over time in size/shape to support the different finished pump, target engine applications GM needed....Comment
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