CRG Discussion Forum

Camaro Research Group Discussion => Originality => Topic started by: red69 on November 06, 2021, 02:55:49 PM

Title: 1969 Z-28 Engine Paint Detail Questions
Post by: red69 on November 06, 2021, 02:55:49 PM
I have the original spark plug wire brackets (the stands that bolt to intake manifold) for my car. They've been painted orange in the past, what was the finish originally? Also the PCV elbow pipe in the left valve cover, semi-gloss black?
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: x66 714 on November 06, 2021, 03:35:10 PM
The LH (driver's side) should have the pcv. The hose should be a preformed 90 degrees from the pcv to the carb....Joe
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: 169INDY on November 06, 2021, 04:28:19 PM
red69, might be referring to the steel elbow pipe on the pass side valve cover that connector a short section of rubber hose to air cleaner base elbow.<?>
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: red69 on November 07, 2021, 03:28:13 PM
Yes I typed in the wrong side on the PCV pipe I meant right side valve cover 90 degree pipe to hose that connects to air cleaner.
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: x66 714 on November 07, 2021, 05:07:44 PM
My observation on fresh air 90 degree tubes are, big block is phosphate & small block is black zinc like the AIR tubes for the smog.....Joe
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: 169INDY on November 07, 2021, 05:47:33 PM
Bingo ^^ Correct.

Personally I have found it difficult to replicate the Black ZInc from a Home restoration perspective.

THis is my local plater whom can perform "BLACK ZINC"

http://tfcplating.com/services/
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: red69 on November 08, 2021, 01:35:12 AM
Thanks for the info I'll check it out. Still looking for the finish on spark plug wire loom brackets. The ones that bolt to the rear of the intake manifold.
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: Edgemontvillage on November 08, 2021, 03:29:01 AM
Yes I typed in the wrong side on the PCV pipe I meant right side valve cover 90 degree pipe to hose that connects to air cleaner.

The 90 Degree Pipe you're asking about on the right (passenger) side valve cover is PN 3923260 and it was used on several Chevrolet small block applications. For the 69 Z/28 it's referenced in the AIM Z28 A5 on page 473. Originals were finished in a semi-transparent bronze chromate rather than paint or phosphate and the chromate color range varied from gold to brown. Later GM service replacements and repops are typically painted black (Goodmark's repop is in the ballpark). Below is a photo of the original pipe from my 22K mile Norwood 2B RS/Z that shows a small section of the surviving bronze chromate finish as well as an early GM NOS pipe which is close in color. Heat cycles degrade the finish over time. Duplicating the finish is difficult and to my knowledge there isn't a commercially available product that works well. Some guys have come close by heating oil to the burning point however with mixed results.

(https://live.staticflickr.com/65535/51663316343_6deb2d5e9c_c.jpg)[/url]

Left - original connector pipe from my 22K mile RS/Z28 with residual bronze chromate and Right - an early NOS pipe
(https://live.staticflickr.com/65535/51663921835_29d6334c97_c.jpg)

Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: x66 714 on November 08, 2021, 03:47:30 AM
That's black zinc Lloyd...Joe
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: Edgemontvillage on November 08, 2021, 04:02:52 AM
That's black zinc Lloyd...Joe

Joe, at my shop we do a variety of plating and finishes including black zinc and black dichromate. Black zinc plating produces an unmistakable dark black finish that is deeper than even manganese phosphating. I'm not aware of anywhere it was used on a 1969 Camaro. It was an expensive finish compared to phosphates and chromates. Black zinc is not the finish on the tube.   
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: Edgemontvillage on November 08, 2021, 04:05:36 AM
Thanks for the info I'll check it out. Still looking for the finish on spark plug wire loom brackets. The ones that bolt to the rear of the intake manifold.

The spark plug wire stands were painted Chevy Orange.

(https://live.staticflickr.com/65535/51663833299_5695c7fab1_c.jpg)[/url]

Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: red69 on November 08, 2021, 03:03:06 PM
Thanks for all the info guess my stands were the right finish after all. Wonder when they were painted orange? From the supplier or at the assembly plant.
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: firstgenaddict on December 05, 2021, 05:00:48 PM
They were painted with a brush at FLINT after the engine was painted.
Here is a photo of s May built 69 Z illustrating the excess paint dripped onto the area below the stand.

 
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: firstgenaddict on December 05, 2021, 05:16:50 PM
Lloyd I do not know if it is evident in the photo however the original float adj lock screws have a bevel cut on the lip.
This is a point deduction for Holley carbs with-in the NCRS and if not for Camaros the orig configuration should be noted, FWIW the last carb I sent off to a highly recognized restorer came back with the newer (incorrect) screws as well. I checked my pre resto photos and it had the beveled lock screws when I sent it off. 
Does anyone know who makes the CORRECT tan carb to air cleaner gasket?
I have 2 NOS but am having trouble finding more of them.
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: firstgenaddict on December 06, 2021, 01:06:51 AM
better photo of the beveled float lock screw
Title: Re: 1969 Z-28 Engine Paint Detail Questions
Post by: Edgemontvillage on January 10, 2022, 04:54:39 PM
I believe the float adjustment lock nuts on mine are the same James

(https://live.staticflickr.com/65535/51812836513_64a0e22bab_c.jpg)