'66 L79 crank pulley; faking "Parkolac"

[Gary B.]

Re: '66 L79 crank pulley; faking "Parkolac"

Gary,

No answer yet, but before we decide that the alternate coatings circle 3 and circle 4 are appropriate for 1966, we need to know the date they were added to the print.

Ronald,

I understand. Is it possible to find the dates that those notes were added to the GM document?

Gary

[John H.]

Re: '66 L79 crank pulley; faking "Parkolac"

Is it possible to find the dates that those notes were added to the GM document?

Gary

Gary -

Yes - if someone has the full print, it'll be in the revision block.

[John D.]

Re: '66 L79 crank pulley; faking "Parkolac"

john
The optional coating: phosphate plus spray coat with BF Goodrich A-1256-B black rubber resin base or equivalent to a 0.0004 minimum was added to the drawing on 10-18-68.

An underbake test specification that 5 drops of ketone on a rag should yield no transfer of coating was also added at that time.

john

[Gary B.]

Re: '66 L79 crank pulley; faking "Parkolac"

john
The optional coating: phosphate plus spray coat with BF Goodrich A-1256-B black rubber resin base or equivalent to a 0.0004 minimum was added to the drawing on 10-18-68.

An underbake test specification that 5 drops of ketone on a rag should yield no transfer of coating was also added at that time.

john

John,

Do you know the date for the Parkolac coating? Presumably that pre-dates the rubber resin option.

Gary

[John D.]

Re: '66 L79 crank pulley; faking "Parkolac"

gary
It appears to be part of the original spec when the part waqs drawn in december 63

[Gary B.]

'66 L79 crank pulley; faking "Parkolac"

That would mean the only coating post-phosphating on these pulley from '63 until Oct '68 was the Parkolac.

So, back to question # 1. How can one fake parkolac?

Gary

[Gary B.]

Re: '66 L79 crank pulley; faking "Parkolac"

PS. I guess this also means the the "rubber resin" language in the latest edition of the '66 TIM&JG may need to be removed.

Gary

[Ronald L.]

Re: '66 L79 crank pulley; faking "Parkolac"

Gary,

I talked to Parker Chem (Henkel now adays).

What we need to be completely sure of the composition, is to get the old MSDS sheet for Parkolac 30. They don't have that since it was discontinued many years ago. Expecting that a base family of coatings use essentially identical ingredients, I asked about the Parkloac 2945 that was discontinued last year. It was a water diluted coating that in the notes they found references to application over black oxide. Now, if it was a wash solution over black, you would not pick up the brown color too much. It dried tack free by air. The reason it was discontinued last year was due to the base ingredient no longer being made.

Off hand I don't have a source for old MSDS sheets, we'll keep looking.

[Gary B.]

Re: '66 L79 crank pulley; faking "Parkolac"

Ron,

Thanks for checking into this. I appreciate the information.

Gary