Mercury Cougar Owners banner

1 - 12 of 12 Posts

·
Registered
Joined
·
1,056 Posts
Discussion Starter #1
I finally had the time to pull the starter and check the engine casting numbers. I found C6AE-6015-C or it could be C8AE-6015-C (that second digit is hard to ID!) with a date code of 7F5. So from what I read from previous threads the date the engine was cast is June 5, 1967 (or 77, 87). So this would confirm that the engine number is C6AE instead of C8AE. And in turn that would indicate that the engine is a 289 instead of a 302....or is June 67 the time when they start building engines for the 68 models?? :1zhelp: Does anyone know what model line the engine came from (AE?).
 

·
Contributing Sr Motorhead
Joined
·
5,470 Posts
The casting number has nothing at all to do with what car line the engine came out of. It simply says that the particular part (engine block in this case) was last modified or changed and the cost of the engineering change was charged to the car line indicated. 'A' in this case being full size Ford. The 'E' simply is an engineering code. The casting number is not the Ford part number. As you noted, the engine could be a 1967 289, or it might also be a 1977 302. An 87 would most likely be fuel injected so it would not have a fuel pump boss on the block.

To find out what car line the engine was originally in, you'll have to look at the serial number stamped into the rear of the block just below the driver's side head. In your case if it is original I'll bet it was 7F(xxxxxx). 'F' being Dearborn and home of the Mustang/Cougar line. Mustangs and Cougars were also built in 'T' - Metuchen NJ, and 'R' - San Jose CA. If you give us that second character I can tell you what assembly plant the engine was used. From there we can tell from the sequential number (the last six digiits of the engine ser no)if it was Ford or Mercury.

Now, as to whether you have a 289 or 302, that would depend on the crank and pistons. The same block was used for both. The bore size being the same for both. The 289 having a slightly shorter stroke than the 302's 3.00" stroke. If the engine has ever been rebuilt, who is to know what the previous owner did! Heck, my buddy is now running a 347cu in stroker '302'. You can't tell by looking at the block or heads!
 

·
Registered
Joined
·
1,056 Posts
Discussion Starter #4
Thanks Cougrrcj, the serial number stamped at the back of the block is either 6F205343 or 8F205343. Not my eyes this time!!:rolleyes: The first digit is only partially visible...looks only half stamped. It's a small diameter circle though so I'm suspecting it to be an 8.
 

·
Contributing Sr Motorhead
Joined
·
5,470 Posts
MM, Ooops! I knew that!

Bruter, based on the serial number of your block we can verify that it was put in a car assembled at the Dearborn assembly plant, and it was installed in a Ford. Ford serial numbers started with 100001 and up to 499999 and Mercury used 500001 and up. Of couse, Ford didn't build 400000 cars at Dearborn, but they built over 100000 as evidenced by your serial number starting with a 2.

OK, with that out of the way, we also know that Dearborn was the assembly plant for Mustangs and Cougars and not anything else that I know of. That means that your block was originally installed in a Mustang. Here's where I'm getting confused. The engine serial is either a 66 or 68, but the build date of the engine puts it early June 1967. I'm not sure when they make the model year changeover back then, but I have seen cars built until late July (my buddy's 73 Mach has a build date of July 21, 1973) Did they have that big of a stockpile of engines already built that it could have been made a month and a half ahead of the car build date? No, that can't be the case since your serial number starts with a 2 indicating it was a late-built car, not an early one. Hmmmmm, curious-er and curious-er. A late 68 with a late 67 built engine? Ok, what was the deal with the leftover 289s from 1967 being used in 68. Were they used in early-built cars or late-built cars? I'm not up on the earlier generation Mustangs and Cougars or small blocks either for that matter... Even a Senior Motorhead can still learn a few things!
 

·
Registered
Joined
·
1,056 Posts
Discussion Starter #6
That's great info Cougrrcj!!! Thanks. We're getting closer to determine if its a 289 or 302:) I wish Ford were a little more precise in the casting of the numbers 6 and 8!!!
 

·
Registered
Joined
·
1,832 Posts
Cj, I KNEW you did, just trying to keep someone else from getting confused. I expect a Cleavland fan to make that mistake. mm
 

·
Registered
Joined
·
1,056 Posts
Discussion Starter #8
To continue this saga....I was "monkeying" around the engine and was checking the timing....first time doing this. The degree marks on vibration dampener were barely visible so I checked my reference material and noticed that the degrees and pointer did not match those of a 289...but did match those of a 302!!:confused: I was also on Fomoco.com and was informed that the stamped vin on the back of the block was most likely 8F205343 as Ford did not stamp the vin on 289 blocks in 1966 and earlier. So then..could this have been a very early 302 built in June 1967 and installed in a late production 68 Mustang??? Hey, maybe I have a prototype engine...lol :p:
 

·
Registered
Joined
·
1,056 Posts
Discussion Starter #9 (Edited)
...Another theory...It could be an engine that was assembled by a PO at some time with different components!? making it a "mutt" engine !!:p: ....but we still have a June 67 (77?) engine installed in a 8F205343 VIN Mustang!! Knowing that there is some confusion about sequential numbers...maybe it was an early Mustang? Could that partial VIN be for a 1978 Mustang?
 

·
Registered
Joined
·
1,056 Posts
Discussion Starter #10
A Summary!!!

...the thread that never dies!!! lol :p:

Ok, did some more "monkeying" and found more numbers...here's what I have so far... The block was cast on June 5, 1967 or 1977 (7F5). The engine build date, located near the distributor is June 1, 1968 or 1978 (8F1H) ... The partial serial number near the firewall is 8F205343 ...which, according to Cougrrcj indicates the engine came from a 68 Mustang...the intake manifold's number is C8AE-9425 B A .... I got off my fat *** and pulled the valve cover and found a 289 stamp and a build date of 8E31, so May 31, 1968 or 1978. And finally, the timing marks and pointer match a 302 instead of a 289!!

So my opinion is that all the numbers seem to point towards a 302 instead of a 289. Did they use 289 heads for a 302? Any other opinions??
 

·
Registered
Joined
·
63 Posts
same question!

I put my 68 up on the rack and pulled the strter to find if I have the original engine and I too found the # C6AE-6015-C. Some of the #'s on the intake, and the valve cover emissions sticker led me to believe that my car may not have the 289 that the VIN# says it has, but a newer model 302 possibly from a larger car (LTD?). Does this casting # actually tell us if it is a 289, or a 302?
 
1 - 12 of 12 Posts
Top