Hey guys, new to the forum. Big fan. I've got a 1969 Mercury 2bbl 390 engine, I think. It's a C7ME-A block, C6AE-C Rods, C8AE-H Heads. The motor is std. bore 390 with very little ring-ridge. Date code on the block is 8A11, heads 8A3 and 7M22. My question to you guys are how to read the CUN.
The number is 8B515229. I'm just curious if its possible to figure out what kind of vehicle this motor came from by deciphering the number. The other substantial number I found on the block was on the front/drivers pad, (5 or 8)A16E That, and my other question is in regards to the one head. 7"M"22? Didn't know there were 13 months in a year....? Any help from the FE gods would be MUCH appreciated.

Nick

 

The letter "I" was skipped in the date codes as it could be confused for a 1. So A-M Jan-Dec skipping the letter I = 12 months. The late Dec 67 date code on the one head and the early Jan 68 on the other fit the timeframe involved. Same with the block.

The rest is
8-year 68
B-Oakville Canada assy plant
?
?

Next should be body serial code, engine code and consecutive unit number. Which seem to be missing or my 68 book does not list them.

 

Is it Possible that it would be listed for 1969, being cast and assembled in the EARLY part of that year?

Nick

 

No. 69 production would begin sometime July-Aug 68.

 

The engine was cast in 1968, but when was it installed in a vehicle? It could be 1968, it could be 1969, or?

How long a time frame after a block or head is cast, seasoned, then finished before it ready to be installed?

Which assembly plant built the car? Which assembly plant was the engine shipped to?

C8AZ-6049-M (360/390) heads were used thru 1971 on cars, 1972 on F100/350's. C6AZ-6200-D (390) rods were used on cars and trucks thru 1970.

While not proof positive, it would be interesting to see what the Carburetor and Distributor ID numbers are. The carbs triangular shaped tag will be found on the airhorn (if not missing). The dizzy number is stamped into the base just below where the edge of the cap rests. 1969 390's used a triple sheeve pulley that was different than 1968. It will have a ID number on it.

The C7ME block was used in all FoMoCo vehicles, not just Mercury's.

 

Bill I believe under normal conditions 30-90 days depending on the assy plant was the norm. But I'd think anything is possible. My 68 Cougar has a 68 Jan 8 build date at the San Jose assy plant. My engine has all late Aug 67 date codes. At first I thought it was swapped in from another car. But I've been told the UAW strike played into that timeframe causing a pretty good backlog. And that it indeed could be correct. The original carb is long gone. But the engine tag is still there. I'll find out for sure as the drivetrain comes out and I can verify the other dates and vins on the block and tranny etc.... Sheetmetal as well as it comes apart. So we'll see how that all pans out. And what the history really is. But for now I'm just enjoying the car for a bit till that all happens.

 

Oh and from blocks I've had the machined dates have all been from 3 days to 2-3 weeks after the casting date. My 62 406 was 3 days and longer on the 67-70 stuff I've had. On the 62 406 the block and heads all had exact matching date codes which is pretty rare to find. For me anyway. I'm sure in some cases if the block had a defect and was pulled from the line the machine date could be much later. As these were put aside till the defect could be corrected. In my case this was a 71 428 service block I had. One lifter hole needed a sleeve. Block had a early 71 date code and the machined date was several months later. FWIW....

 

I remember that strike quite well. When the UAW struck, we couldn't get any parts till the strike was settled. At that time, the rear axle seals (C4OZ-1177-A) on Mustangs and Cougars were defective, so you can imagine how many 1000's of those cars were sitting unfixed on dealers service lots across the US when the strike began. The seals came in a package of two, and I ordered all the parts at that time for the mega-dealer (Ralph Williams Ford), I was working at then.

I made a mistake just a week before the strike began. I ordered 200 seals, instead of 100. 200 seals gave us 400 based on the package quantity.

Because no one across the US were getting any parts shipments, when we needed something for a car/truck pertaining to body parts, we had to buy them from another dealer.

Most dealers weren't selling anything to other dealers, but when I offered to sell them the seals I knew they needed, as long as they would sell us the body parts we needed, that got us through the strike.

 

My 72 Maverick with the Sprint package has a 200 assembled on April 12th 1972
and the car was built on April 15th. So sometimes things happened real fast!

 

Was the engine cast on 4/12/72, or assembled on that date?

Blocks have to cure (season) after being cast. The curing time can be one to three months, or longer depending on the type of block.

1968/72 Maverick/Comets used the same 200 engine block (D0DZ-6010-B) from 1968 thru 1972.

 

Good to know!!

 

Looks like that mistake worked in your favor Bill!! Also reminded me I need to replace my axle seals too!!! Thanks for the insight on the strike. Interesting to hear story's like that.

 

I should have mentioned that C4OZ-1177-A was the p/n for the 8" axle seals, and that number was only used thru 1968.