Water Pump Bolts '63 Coupe 327/340 w/SHP

[Matthew D.]

Hello all I am new to the forum and this is my first post. I have a 1963 Coupe with a 327/340 with Special High Performance. I am reading in the Tech Manual/Judging guide that the water pump was installed prior to painting. If this were the case then am I to assume to that the water pump bolts are all chevy orange in color? The Idler Assembly is installed on the lower left bolt/stud and the alternator bracket is installed using the upper right mounting bolt. Im confused how the pump could be installed and painted without overspraying the zinc ider stud and the gloss black alternator adjusting arm. Maybe they only used the two other water pump bolts to hold the pump on while painting? Any advice/info would be greatly appreciated. Thanks in advance.

Matt

[Edward J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Matt, I will try and answer this for you, The pump was bolted in place and the idler pulley and bracket were not installed, when the time comes to install the idler pulley, one of the bolts was removed and the stud was installed . This would mean 3 of the bolts would be orange and the stud was black phosphate. The judging manuel gives you the detail of engine painting process, under orange engine painting process in the beginning of the mechanical section.

[Alan D.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Matt, you will need to find out a little more about the production sequence. The Michigan Chapter has some good stuff by John Hinckley, just took a look there but unable to find. Know he did a talk - "MIDYEAR CORVETTE ASSEMBLY PROCESS" at the 2011 NCRS National Convention Technical Seminar

[Michael H.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Matt,

As has been said above, the engine was painted orange at the Flint engine plant. At that point, the water pump and all four water pump bolts had already been installed and would be painted orange also. It is then shipped to the St Louis Corvette assembly plant.

When the engine is dressed at the St Louis plant, those that would include the idler pulley assembly (340-360 HP) had the lower left water pump bolt removed and replaced with the long zincad plated hexagon stud.
At the same time, the alternator brace was added and the bolt replaced with a longer bold that would not be painted orange.

Unimportant side note; for early 63, the alternator brace bolt was not changed/replaced. The existing bolt was used at the St Louis plant so it would still have orange paint on the head but that's not really important. I don't know exactly when the change occurred as it's not shown in reproduction assembly manuals.

[Edward J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Mike, I Also think that there was a blk. phos. stud used on idler pulley, as my Mar car has one. And a small notation on my car it had a black pulley for the idler. I know the JM makes note of both types of the plating on these items for 63.

[Michael H.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Mike, I Also think that there was a blk. phos. stud used on idler pulley, as my Mar car has one. And a small notation on my car it had a black pulley for the idler. I know the JM makes note of both types of the plating on these items for 63.

Edward,

I suppose anything is possible although I've never seen this part plated in black. All that I've seen were plated zincad. (zinc/cadmium) The original GM print calls for zinc or cadmium.

The majority of idler pulleys (not the bracket) seemed to be coated in black paint but some were unpainted.

[Edward J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Edward,

I suppose anything is possible although I've never seen this part plated in black. All that I've seen were plated zincad. (zinc/cadmium) The original GM print calls for zinc or cadmium.

The majority of idler pulleys (not the bracket) seemed to be coated in black paint but some were unpainted.

Mike, I have looked at a few idler pulley studs and they were cad. plated, when I cleaned mine up there were no signs of cad. just a black phos. type finish, so I left it as is was. I kind of thought it might be a hard one to convence someone that has surly been around mid years like you, likely more than I may ever. I could of brought one of those new cad. plated studs at long island corvette but thought its likely one a few.

[Bob J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Edward,

I suppose anything is possible although I've never seen this part plated in black. All that I've seen were plated zincad. (zinc/cadmium) The original GM print calls for zinc or cadmium.

I agree, Michael.
I've seen many original studs through the years and have never seen the idler stud black either......always zincad. Bob

[Michael H.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Here's a GM picture of a brand new 63 engine with a typical zincad plated idler pulley stud. I don't think I've ever seen one of these studs plated anything other than zincad.
In the early or mid 70's, I ordered about 10 of these through parts and I think I still have some left. All were zincad plated.

My new 64 coupe with 365 HP engine had a zincad stud too.

Of all the 63-65 cars that went through Buxbaums in the mid 70's, none that I remember had a black stud.

I would be interested in hearing from anyone that still has an original unrestored stud that is black plated.

Some cleaners that contain mild acid can turn zinc or cad to black. Even cleaners as mild as Aluminum jelly will make it appear black if left on too long.

[Alan D.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Just a little added information - the Safest Rust remover has a ph of 5.25 which is milder than the jelly stuff. If left in the solution for an extended period of time you get a bolt that is black. The solution does not remove the finish (cad/zinc) just the rust so may be some kind of a reaction with the rust. You do not want to get the black on your hands when washing bolt off since it stays for a while despite washings.
In fact I have used the blacking effect on bolts which call for a black finish.

[Matthew D.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Thank you all for your timely and informative responses. My only conflict is the upper right bolt securing the alt. bracket. Was it removed and replaced with a zinc plated bolt or was the original orange bolt used? Thanks

[Edward J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Matt the alternator bracket bolt at pump should be orange.

[Michael H.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Matt the alternator bracket bolt at pump should be orange.

Edward,

Nope. Alternator brace bolt at water pump was installed at St Louis so it would not be painted engine orange. (black plated)

Only very early 63 cars would have used the existing orange painted bolt at the water pump for the brace.

[Edward J.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Mike thanks for that info. I thought they where orange except the stud.

[Michael H.]

Re: Water Pump Bolts '63 Coupe 327/340 w/SHP

Mike thanks for that info. I thought they where orange except the stud.

Edward,

Take a look at the AIM sheet. (sect 6 sheet A4) It shows the bolt/washer and brace with part numbers as being installed at St Louis. If the existing water pump bolt were to be used, there wouldn't be a part number shown for the bolt and there would probably be a note stating "use existing fastener".