71 351C engine markings

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tpj71mach

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I tried searching for a previous thread on this but couldn't find one, I am not sure I am using the correct wording. I am trying to determine the correct engine inspection marking and stamps that would belong on a 71 351C. I like to detail the engines on my builds with all of the stamps and decals and writing that would have been done on assembly or installation, but do not want to get it wrong if I can avoid it. I would like to try and get this as right as I can as far as locations and colors etc. Searching the internet, I see some pictures with large "O-K" on the drivers valve cover, I have seen dome pictures with a smaller "OK" on the vale core and sometimes the same smaller "OK" on the drivers or passenger head. I have also seen a different smaller yellow stamp on the heads. I have seen all of these with and without a white number 3 hand written on the drivers head. It seems that there is a lot of discrepancies and I am trying to determine which, if any, of these are correct. Does anyone have pictures of your original survivor markings or correctly restored marking so I can learn what is correct and where to place them on the engine. I appreciate any help I can get on this, thanks
 
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Your best bet is to try the Concours Mustang Forum:

I know that there are a ton of different markings on these cars, and the markings sometimes change quite a bit even on cars from the same year made in the same assembly plant. Some things are pretty standard like the color codes on parts for the assembly man to know what specific part to use on a specific vehicle, but others can vary quite a bit. I have taken photos of my differential markings, and they are a little different an in a different place than others I have seen. The OK, or OIL markings would just need to be there, in a relative area where the inspector could see them. Different guys would put them in different locations, and with obviously different writing. If you are going to do a concours build, you basically need to figure out what is acceptable to the judges, and if you cars markings are not what is in the book for your make, model, and year, you better have very good documentation, that yours was done differently.
 

tpj71mach

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Your best bet is to try the Concours Mustang Forum:

I know that there are a ton of different markings on these cars, and the markings sometimes change quite a bit even on cars from the same year made in the same assembly plant. Some things are pretty standard like the color codes on parts for the assembly man to know what specific part to use on a specific vehicle, but others can vary quite a bit. I have taken photos of my differential markings, and they are a little different an in a different place than others I have seen. The OK, or OIL markings would just need to be there, in a relative area where the inspector could see them. Different guys would put them in different locations, and with obviously different writing. If you are going to do a concours build, you basically need to figure out what is acceptable to the judges, and if you cars markings are not what is in the book for your make, model, and year, you better have very good documentation, that yours was done differently.
Thanks for the info, I am not building a concourse build. I build my cars to drive and enjoy, that said I do enjoy making them as correct as I can and still not worry if it has the wrong color bolt somewhere. My weakness on this aspect is even though I have researched the correct color for example, I often will paint something a different color just because I think it looks better. If there are four thing installed near each other and they are all black I have been known to paint one gray and another a different color to get color separation rather than correct to factory. For example, I know the springs and shocks should be black but I liked this better and my car is not a rare numbers match uber-valuable car so....

Mach 1 232.jpg
 
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That's some seriously good looking brake/suspension!
Love it!
One detail that I can't even see: there is a pressure plate behind the callipers, sandwiched with the flexible. I have changed these last year on my 73 and the damn cheapo things already started to rust. So may you live in a wet air state like me, I'd consider spray them while you can easy. I should have restored the originals that were not as bad after 50 years!
 

tpj71mach

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That's some seriously good looking brake/suspension!
Love it!
One detail that I can't even see: there is a pressure plate behind the callipers, sandwiched with the flexible. I have changed these last year on my 73 and the damn cheapo things already started to rust. So may you live in a wet air state like me, I'd consider spray them while you can easy. I should have restored the originals that were not as bad after 50 years!
Thanks for the advise, I painted every thing before I assembled and clear coated the things that I wanted to keep natural finish look. The car will never see rain or snow but I am also in a climate that can get very humid and cause unprotected parts to rust just in the air.
 
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Modified 1970 Mach 1 M-Code with a 351C 4v Manual

I tried searching for a previous thread on this but couldn't find one, I am not sure I am using the correct wording. I am trying to determine the correct engine inspection marking and stamps that would belong on a 71 351C. I like to detail the engines on my builds with all of the stamps and decals and writing that would have been done on assembly or installation, but do not want to get it wrong if I can avoid it. I would like to try and get this as right as I can as far as locations and colors etc. Searching the internet, I see some pictures with large "O-K" on the drivers valve cover, I have seen dome pictures with a smaller "OK" on the vale core and sometimes the same smaller "OK" on the drivers or passenger head. I have also seen a different smaller yellow stamp on the heads. I have seen all of these with and without a white number 3 hand written on the drivers head. It seems that there is a lot of discrepancies and I am trying to determine which, if any, of these are correct. Does anyone have pictures of your original survivor markings or correctly restored marking so I can learn what is correct and where to place them on the engine. I appreciate any help I can get on this, thanks
Hi TPJ71Mach,

I hope these pics help. They are from my 73 vert with a 351 2V Cleveland. I have more covering the undercarriage, C6 Trans, driveshaft, axle, shocks, and leaf springs if you are interested in those tags and paint marks. The green paint on the alternator is for a 60 Amp. The color was different for other amp models. For example, the 42 amp paint mark was a yellow/gold color. The same is true for the springs, air cleaner snorkel, and driveshaft, leaf springs, etc.
 

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tpj71mach

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Hi TPJ71Mach,

I hope these pics help. They are from my 73 vert with a 351 2V Cleveland. I have more covering the undercarriage, C6 Trans, driveshaft, axle, shocks, and leaf springs if you are interested in those tags and paint marks. The green paint on the alternator is for a 60 Amp. The color was different for other amp models. For example, the 42 amp paint mark was a yellow/gold color. The same is true for the springs, air cleaner snorkel, and driveshaft, leaf springs, etc.
Thanks, those are exactly the kind of pictures I was hoping for to help me see where these marking and stamps and labels go. Wow I love your attention to detail! Great job! Did you refinish your wiper motor? If so how did you replace the lettering? I cleaned mine up but would have preferred to repaint the black but was afraid of losing the lettering.
 

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Hemikiller

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Here's a couple pics from a 71 that was for sale in NJ a few years back. This is an M-code 4V car, the H-code may be different. If you're just going for a "factory" look, then I'd just pic a good example and follow it. Ignore the emissions decal on the fan shroud, that's obviously an owner add on.

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tpj71mach

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1971 Mustang Mach 1 351c FMX trans and 9 inch rear end
Here's a couple pics from a 71 that was for sale in NJ a few years back. This is an M-code 4V car, the H-code may be different. If you're just going for a "factory" look, then I'd just pic a good example and follow it. Ignore the emissions decal on the fan shroud, that's obviously an owner add on.

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Great, thank you! I am just looking to go for a "mostly factory" look. Even though my car is an H code, it did not have an engine at all when I purchased it. I am building a 71 351C 4V M code engine to look mostly stock on the outside but a bit more on the inside. On the outside I am going for the day-two look, aftermarket intake and headers but otherwise stock appearing. That is why I am trying to find as correct as possible markings. I appreciate the help and the pictures, thanks again.
 
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I wasn't going to post these pics as they are for an M code, but these decal that are left are for sure original. I didn't take many at the time I got the car in 08, wish I had. At this time, the motor had never been touched other than a Holley carb, belts and hoses, the usual stuff. I'll also add a pic of how I detailed it now, i.e. engine code. Sorry I don't have more.
As for the wiper motor, you can get a new stamp made to replicate what you have. A friend did this for his car, but I did not bother (yet) for mine.
 

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tpj71mach

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1971 Mustang Mach 1 351c FMX trans and 9 inch rear end
I wasn't going to post these pics as they are for an M code, but these decal that are left are for sure original. I didn't take many at the time I got the car in 08, wish I had. At this time, the motor had never been touched other than a Holley carb, belts and hoses, the usual stuff. I'll also add a pic of how I detailed it now, i.e. engine code. Sorry I don't have more.
As for the wiper motor, you can get a new stamp made to replicate what you have. A friend did this for his car, but I did not bother (yet) for mine.
Awesome, thanks for the pictures! That is how I am hoping to do my engine compartment. I think I will go with the wiper motor as is for now and maybe take it off and paint over a future winter when the car is "done" and I can get down to the little details.
 
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Thanks, those are exactly the kind of pictures I was hoping for to help me see where these marking and stamps and labels go. Wow I love your attention to detail! Great job! Did you refinish your wiper motor? If so how did you replace the lettering? I cleaned mine up but would have preferred to repaint the black but was afraid of losing the lettering.
Thanks! Yes, I refinished the wiper motor casing and the Yellow Chromate access plate. I graphically reproduced all my letter/number stamps and then sent to RubberStamps.com (i think it was them) online, and then to keep the cost down, I had them just create the rubber stamp without the stamp handle or applicator. I did this with the OK, wiper, snorkel, headlight buckets, and my Bosch factory power window motors. I also made the square inspection stickers, because I read on the Cobrajet website, or somewhere that the over-the-counter repros are not the correct size and have rounded corners. The site provided the exact size for them. Front Door Power Window Motors.jpg
 

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tpj71mach

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That's a great idea, obviously you were able to figure out the font style and size to match the originals. I'm not sure I'm smart enough to figure that out. LOL
 
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