Topic: 69 Mach 1 Differential Restoration

[G Wood]

I am ready to assemble the rear differential of my 69 Mach 1. All parts are painted correctly and I have a black gasket for the center section (pumpkin) to the differential. Did the factory use sealant on the gasket and if so what color. How much did they allow to ooze out onto the differential surface (if any)?

Thanks

[J_Speegle]

Not aware that any year Mustang rear end was originally coated (at the third member to housing gasket). Never found any remains of such. Believe, like many other original gasket, Ford let the gasket do its job

[Bob Gaines]

I am ready to assemble the rear differential of my 69 Mach 1. All parts are painted correctly and I have a black gasket for the center section (pumpkin) to the differential. Did the factory use sealant on the gasket and if so what color. How much did they allow to ooze out onto the differential surface (if any)?

Thanks

I would like to mention because of the point in your job that you are at and since you were concerned enough to ask about if gasket sealer or not. A seldom remembered detail is that before putting in the center section - to be historically correct the face of the housing where the center section mates to is a machined bare steel finish and not painted. So you would see the surrounding semi black housing finish ,the bare metal of the flat matting surface (however you choose to portray that bare metal look) and then areas of  black paper/fiber gasket material. It is a bugger to do this after the fact. I hope this helps. Bob 

[G Wood]

Bob:

Thanks for pointing that out, I do have that correct.

Jeff:

Thanks for clarifying.

Garth

[G Wood]

What is the best method to replicate the numbers on the differential and center section, a small paint brush, grease marker, etc?

Also I beleive there is a yellow or white stripe around the axle tube ends (near backing plate) for a 69, is that correct.

Thanks

[J_Speegle]

What is the best method to replicate the numbers on the differential and center section, a small paint brush, grease marker, etc?

Depends on the specific mark, most were paint (applied with a brush in most cases) some (a few on some applications) were the per mentent crayon

Also I believe there is a yellow or white stripe around the axle tube ends (near backing plate) for a 69, is that correct.

On some 9" in 69 the end of one tube (around the weld) has been found but not on all original rear ends. And (from original examples) it has been found on the passenger end and on others the drivers - IMHO no clear pattern so I've been normally suggesting leaving it off unless you find one on your car.

And when found it is a bright yellow - never seen white

[Bossbill]

I've seen the yellow paint on the 69 and later cars, but never on the earlier  9".
The Perkins article shows this very visible yellow.
So prior to 69 all bare housings were semi-gloss everywhere except for the diff gasket face?

[J_Speegle]

I've seen the yellow paint on the 69 and later cars, but never on the earlier  9".

Assume your referring to the end of the housing tube mark. On what later cars have you seen that mark on?

So prior to 69 all bare housings were semi-gloss everywhere except for the diff gasket face?

No 69 and later housings in my experience, notes and pictures had the same bare face to insure the gasket sealing.

[69GT350H]

A comment with photos from my build thread. As noted, these photos are from an April 2, 1969 build:

Rearend housing is all black except for the face where the third member and the backing plates attached. In the picture the studs for the third member were darkened after the picture was taken. Pictures are from that GT350 built about 100 cars before yours (sequential numbers) April 14th verses April 2nd real build dates - so about 2 weeks before yours.





Backing plates to rearend housing are a dark natural finish (unpainted) The wheel cylinder is natural cast iron and those retaining bolts are unpainted





Third member showing most of the machined surfaces and finishes. Snubber not installed at the moment so that the upper machined surfaces could be seen





Faces of the brake drums were blacked - out

[Bossbill]

Assume your referring to the end of the housing tube mark. On what later cars have you seen that mark on?

I think we're tripping over each other's words.
I'm referring to the yellow paint in both the Perkins' article and in 69GT350H's 2nd pic.

No 69 and later housings in my experience, notes and pictures had the same bare face to insure the gasket sealing.

I'm not sure where we missed here either. The housing is painted black except for the gasket surface. As in the third pic.

Thanks for the pics 69GT350H.

[J_Speegle]

I think we're tripping over each other's words.

No problem - think we have clarity now