73 project (advice wanted)

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In looking at the many posts from my fellow enthusiasts in this forum i can tell you they have offered some great advice already. Not to beat a dead horse, but the suggestions by "[B]MikeGriese[/B]" are dead on - especially about needing to purchase and USE a pair of jack stands. Years ago, while in the Army, I knew a soldier who changed his own oil. He neglected to use a jack stand and ended up with his chest being crushed. He survived, somehow, but he had a long, painful recovery. Please, don't you end up like him - or worse.

Another member advised you to check the vacuum line leading from the intake manifold to your transmission vacuum modulator. You can get a vacuum tester (good to have one) and make sure the modulator valve diaphragm is not leaking. If it is leaking or disconnected from the vacuum line your 1-2 upshift will be late, very late, and when it does slam into 2nd gear it will be at a fairly high road speed (40 - 50), and it will either go into 3rd gear very late, at a very high speed (70 or more), or it may not shift into 3rd gear at all. Those auto transmissions are very durable, please do not be in a hurry to replace it with a manual transmission., If you simply MUST replace it, consider getting a later model Automatic Overdrive (AOD). But, unless you have a really good reason to do so I would stick with what you have.

The ignition systems on those 73Mustangs is quite simple. Unless you plan to do some serious track racing I would not bother "upgrading" it to an electronic system. Despite claims made by those who sell electronic conversion kits, the stock system is fie unless it has a worn distributor shaft/bushing, worn breaker plate, the vacuum advance diaphragm vacuum line is disconnected or connected incorrectly, or the vacuum advance diaphragm is ruptured. I have a few YouTube videos re: the distributor, vacuum advance diaphragm, vacuum hose routing, that I think would be well worth your watching. Over time I will be doing ever more videos with Lynda (wife), and I encourage you to watch those videos, and videos done by others, to learn ever more about your car.

I have a nice little library of electrical schematics that I have annotated, show corrections to a few publisher errors, and am willing to share with you. The file is too large to attach to this posting. But, you can get the same schematics, and other manuals (shop) that will be invaluable to you from Forel Publications at:

https://www.forelpublishing.com/clickbank/index.html
The various manuals are in PDF file format, and are very reasonably priced.

Malachi, I sincerely suggest you feel free to reach out at ANY time with ANY questions you have about your Mustang. Between myself and our other enthusiasts you are going to find you have tapped into a huge resource of very experienced folks. You are also welcome to email me at [email protected]. I look forward to seeing photos of your Mustang, and hearing from you either through this forum, via my email, or both.

Here are some of the more relevant YouTube videos I put together re: the ignition system on our 73 Mustang Convertible's 302, which is very similar to your 351. I also attached an engine emission systems and vacuum schematic snippet from the 73 Shop Manual Volume 6.










I have a lot more videos on our YouTube channel (Gilbert Hale). Please feel free to peruse them to see what else I have that may be of use to you. And, if you have a question about something not covered in our videos yet,, let me know as often we choose to cover a video subject based on questions from other folks.

Thank you very much!
 
Welcome from RI. Do you know what transmission you have? If the information was in this thread I did not see it.

Ron
i have checked out my transmission with my grandfather who was a mechanic, he said that i need to either rebuild or swap it. how mard would it be to swap to a c6 since i currently have a c4?
 
That is unusual to have a 351C of any variety backed by a C-4. Typically the 2 barrel engines were equipped with an FMX or a sometimes a C-6. The 302 and the very rare inline 6 powered cars used the C-4. Check your door data plate and see what the transmission code is.

Ron
 
That is unusual to have a 351C of any variety backed by a C-4. Typically the 2 barrel engines were equipped with an FMX or a sometimes a C-6. The 302 and the very rare inline 6 powered cars used the C-4. Check your door data plate and see what the transmission code is.

Ron
FYI...both of my 72’s are 302/FMX . Maybe that’s all they had on hand when mine were built.
 
FYI...both of my 72’s are 302/FMX . Maybe that’s all they had on hand when mine were built.
Now that you mention it I have seen 302 powered cars with an FMX. But more often I have personally encountered them with a C-4. You are right in that Ford may have just used what they had on hand to keep the line moving. I actually prefer the FMX over the C-4.

Ron
 
Welcome to 71-73 Mustangs. I think you will find great advice here. Many of us are members of both VMF and this forum. I prefer this for my 73. One thing most of us remember when we were 16 with our first car. It was that we spent money on parts before we fully engaged our brains. You cite both electrical and tranny issues. So, let’s discuss each in detail before you buy fix it parts. There are folks here who can likely narrow the problem down to one or two parts. So, when you get the time, outline each problem in as much detail as you can. What do you do and how does the car respond. Is the car hot or first thing cold? If your car is stock, the parts are simple and it might be a very simple problem to solve.

Also, you should get a set of Ford service manuals; the books the dealers used to fix the cars. They are available in both paper form and as a PDF.

Again, welcome to the group.
I agree with Steve re: the need for some manuals. My Go To site for most of my manuals is Forel Publications. There, for the 1973 Mustang, you will find the shop manual, the electrical schematics (excellent colorized manual), body parts, parts and accessories, etc. In Volume 6 of the Ship Manual you will find an excellent collection of emission control system information, to include the engine vacuum schematics. The vacuum schematics for 351 4v carburetor engines are missing, but those are attached to this post I am making. The manuals from Forel are in PDF file format, and are very reasonably priced. Their 1973 web site for their PDF manuals is:

https://www.forelpublishing.com/clickbank/index.html#1973
Ciao!
 

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Contact Jim Osborne Reproductions, Inc.
101 Ridgecrest Drive
Lawrenceville, Ga. 30046
770-962-7556

These guys have several manuals for the 1973 Mustang, I have done business with them for many years, great folks, they know their Mustangs and Fords. They have a lot of different manuals like Mustang Interior Assembly Manual, Mustang Weld Assembly Manual, Mustang Body Assembly Manual, Mustang Electrical Assembly Manual and more
 
Greetings!
I have been rather busy and my Mustang has had a different transmission installed. I now have the FMX. I have a few questions that I was unable to find a answer for.
815: does anyone know what this selector switch may be. (under the normal selectors) It has a left side and right, neither are labeled.
814: What does the far left flip switch do, and what used to be where the hole is.
806: my rear bumper seems to stick out more than all of the photos I have seen. It also seems to be a different bumper entirely.
807: this is an upward angle of the angled piece of metal the bumper sits on.
805: my front bumper is made out of rubber. This seems very strange to me, it also is a slightly different shade of yellow. Any ideas or explanations?
(edit) 821: I have no idea how to change my front or rear headlight bulbs.
Thank you all for the great advice and assistance!
 

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815 - that is not a factory switch, so it's anybody's guess what it is for
814 - the hole is for the parking brake indicator on a '73. You should have a seatbelt light over the glovebox. The small switch on the far left is not stock, so good luck with that one.
806 - this could have a couple of different causes, but it's kinda hard to tell from the photo. The bumper could have been replaced with an earlier bumper, the bumper brackets may have been replaced with earlier parts, the bumper is bent, or...?
807 - Can't really tell from the photo, but that doesn't look like a standard bumper bracket.
805 - that is a normal bumper. It's made of urethane. It's possible the paint mismatch is from the bumper being painted, or the bumper paint fading, or the rest of the car got painted.
 
Your best bet on the two non factory switches is to chase down where the wires from them go. Odds are they don't go to anywhere and you can just remove the switches. Back in the day we loved installing things like aftermarket driving lamps and stereo amplifiers or tape decks that required an a-b switch that would transfer signal from the radio to the tape deck, all kinds of stuff like that and then those would get removed but the switches were often left behind wired to nothing. If you chase down the wires attached you'll probably find you can just remove those switches and toss them. Just a suggestion on where to start.
 
The tail light sockets are removed by turning them counter clockwise approximately a 1/4 turn and the socket will come out of the back of the lamp. You then push the bulb into the socket while turning the bulb counterclockwise and the bulb will come out of the socket.
 
815: what they said
814: aftermarket something. If that's a switch for the rear defroster, then the hole is for the indicator light.
806: 73 rear bumpers were spaced out away from the body further than 71-72. You're missing the urethane quarter filler pieces
807: can't see, pic too small
805: Factory issue for all 73 Mustangs was a urethane bumper with a 5mph impact rating, not to be confused with the 71-72 Mach1 urethane bumper.
821: Time for a shop manual

https://fordmanuals.com/product/1973-ford-car-shop-manual-volumes-i-vi/
 
MMoyer, there is a LOT of great advice and knowledge on this board. I bought my '73 H code , 9 years ago and I knew very little about it then. Mine was in a similar condition to yours; drivable, but a little jankey in certain ways. Just by reading threads on here I have been taken to school. Don't just "jump in" read and ask these guys.
The best thing I've learned is that if your ride has a 351 Cleveland, treat it well. That was a great motor!
I'm looking forward to seeing how your project progresses.
 
Hey guys, I haven’t been in here in a good while.

Here’s an update: fixed some of my front suspension just some control arm stuff, new ignition system msd rotor,cap and coil, new plugs wires and solenoid
Painted my valve covers and air cleaner housing for insurance
Everything runs and drives great!
I have put around 300 miles on it now

So anyways, my next goal is exhaust. I am looking for some headers. Long tube is great but I am thinking about getting something not so hard to install. But all the headers I find online are either crazy expensive or don’t fit with power steering. Any advice would be very appreciated! Thanks guys!
 
If you have a 351C, the Hooker Super Comps fit well and are fairly easy to install. I've been running these for a couple decades with no problems. Use quality gaskets and hardware.
 
Hey guys, I haven’t been in here in a good while.

Here’s an update: fixed some of my front suspension just some control arm stuff, new ignition system msd rotor,cap and coil, new plugs wires and solenoid
Painted my valve covers and air cleaner housing for insurance
Everything runs and drives great!
I have put around 300 miles on it now

So anyways, my next goal is exhaust. I am looking for some headers. Long tube is great but I am thinking about getting something not so hard to install. But all the headers I find online are either crazy expensive or don’t fit with power steering. Any advice would be very appreciated! Thanks guys!
The long tube headers are easy to install with the long motor mount bolts pulled and the motor lifted 1" use a board to distribute the weight of the jack on the pan or lift from the top. The Hooker headers are only 300. You'll need reducers to go to your pipes, which you'll most likely want to also upgrade.
 
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