Topic: 69 Mach one

[MarksMustang]

Just new on here. This is a 69 Mach One clone that I just bought and plan to use for daily driver in the Summer Months!

[muncher]

Hi There
Very nice. I do like this shape. Gonna be my next buy eventually.

[stang98]

I absolutely love the red. Sure is beautiful 

And welcome!

[Soaring]

Welcome to the site.  Tell us what you have for a power plant. 

[MarksMustang]

351 cleveland with edelbrock 4V. Has MSD ignition, headers, and dual exhaust. Supposed to bave a p inch posi rear, but I think it is 8 inch, and not sure on the posi yet....I am not sure how to tell on these Fords yet! It has   an auto tranny, I think it is C-4. I do not have it on the road just yet. Still need top work out some lighting and electrical issues to get it inspected!

[Soaring]

Raise up the driver's side  off the ground and tryl to spin it.  If it won't spin then you have a posi trac.  If it will, then you have an open rear. 

[MarksMustang]

I jacked up the driver side, and no spin either direction...a little play both ways, but will not spin. Whe I punched it down on the pavement, it layed 2 strips. One guy told me that he thought it was an 8 inch, but I do not know how to tell the difference between the 9 and the 8. I was a bit confused as to whether it was posi or not  becaue when I jacked up the whole rear end and spun the wheels, they did not go the same direction, and I always thought that was one way to tell posi....maybe it is different with Fords...

[Soaring]

Chevy uses the term "Posi-traction" but it is basically the same with Ford. If you can lay two stripes, it's a Posi-traction rear. 

[Soaring]

Chevy uses the term "Posi-traction" but it is basically the same with Ford. If you can lay two stripes, it's a Posi-traction rear, meaning that both tires are pulling at the same time.   

[MarksMustang]

Great! How can a guy tell the difference between a 9 inch rear and an 8 inch. And how 'bout the difference between FMX, C-4, and C-6 ? This one has the hurst line shifter where you have to pull the lever back tp shift!

[66GTKFB]

Automatic transmissions: short course -
FMX - cast iron housing (a magnet works)
C4 - bell housing is removable, alumunum housing.
C6 - bell housing is part of whole assembly, alumunum housing.
C4 tranmissions have several variations; 5 bolt bell housing; 6 bolt bell housings; 6 cylinder low duty; V-8 medium duty; High Performance; two speed/three speed driving range; selectable 1st, 2nd and 3rd driving ranges; floor shift; column shift; overdrive. All the above are more or less mixed to make up a transmission for a particular application.
C6 transmission are heavy duty for 352, 390, 428 and 429 engine uses, although a smaller bell housing type was created for use in 71 on small blocks, 302, 351.
Jim

[66FastbackGT]

Nice ride! you are going to really enjoy driving it around,congrats!

[Soaring]

Great! How can a guy tell the difference between a 9 inch rear and an 8 inch. And how 'bout the difference between FMX, C-4, and C-6 ? This one has the hurst line shifter where you have to pull the lever back tp shift!

Here is a pic of a 9 inch differential from Ford.  Notice the"hump".  The 8" is round and smooth.

[MarksMustang]

No hump on mine...must be an 8, but it does lay down 2 strips of rubber when stepped on, so it must at least be posi. I am waiting for a new wiring harness right now so I can get things working well enough to get an insp stickewr so I can drive the car!

[Soaring]

Are you talking about the front, under the dash and rear wiring harnesses?  I so, that will take a lot of time, so plan on it.  Be sure you have a wiring diagram before you start yanking old wire. 

[MarksMustang]

Yes I am. I am having problems with the electrical system. New alt does not want to charge, and When I hit dimmer switch I get low beams, but hit it again for high beams, and all the headlights go out. New headlight switch, new dimmer switch... I re-wired a 73 Charger that had the same sort of problem, and it worked great after I re-wired it, so I just figured I could do the same with my Stang!

[Soaring]

Re-wiring will usually fix the problem but that may be overkill. Try replacing the dimmer switch first.

[MarksMustang]

Well, the dimmer is new, and it puts power out one side when the low beams are on, and  i9t puts power out the other side when the lights go out, so it looks like the switch is working correctly. I mean it is possible that I am wrong about the switch and did the test wrong, but the dimmer looks new. It seems that I am losing power at the fuse box, but I cleaned that all up, and repaired some wires there, but still no luck. I appreciate the suggestions, though!

[Jeff73Mach1]

you have a short somewhere

1st place I would check would be the ammeter if it has one.

[jserio]

Welcome, I am new myself. That is my favorite year Mustang. GL with your new toy.