Engine Stamp Decode

[NolaBoy]

Looking for some help decoding an engine stamp. When I bought my ‘76 the engine had been swapped out. I’m trying to figure out the exact engine that was put in. I have looked online and as far as I can tell it looks like it comes from an ‘87 truck. Is this right? I am having trouble deciphering the other letters and numbers. Any help would be great. Thanks in advance!

Sent from my iPhone using Tapatalk

 

[oldiron]

Looks like cast on march 24 1990. Look on the machined surface on the drivers side of the block just above where the timing cover connects the the engine block. You "should" see numbers stamped there. Those are the assembly date code. Probably something like "0c30" or thereabouts. As far as finding out what it came out of...that's a little more difficult, or impossible alltogether.
Greg

 

[ared77]

C = 60's
D = 70's
E =80's

So the casting number E7T (if I'm seeing that right) does decode as 1987 and "T" is for a truck. But that is what it was originally cast for, many times they used the same casting number block for many years. Looks like 0C24 for the date code so that takes it up to March 24, 1990 like oldiron said. The number hand stamped on the flat pad behind the intake manifold should be the last 8 digits/numbers of the actual vechicle's VIN your engine came out of. Sometimes it's very hard to see, stamped too light, etc. I (just yesterday) found the info on a old block I had in my garage and posted it on a Mustang site. Guy there was able to tell me it was from a 1991 Mustang GT Hatchback and even gave me the full 16 digit VIN!

 

[Broncobowsher]

VIN numbers on the block are the exception and not the norm. If you don't find it, it isn't there.

As others have pointed out, '87 design block made in '90. Could be anything that had a 302 in it. Crown vic, truck, Mustang, even a boat.

 

[oldiron]

VIN numbers on the block are the exception and not the norm. If you don't find it, it isn't there.

As others have pointed out, '87 design block made in '90. Could be anything that had a 302 in it. Crown vic, truck, Mustang, even a boat.

Exactly this^. Trucks and most passenger sedans likely won't have a partial vin stamped at the rear of the block. Some mustangs will but not all. To my knowledge it's been this way since the 60's i.e. higher end vehicles that were more likely to be stolen for the engine got that particular stamping. Of the 4 302's I have, only the '68 galaxy engine has a partial stamp. The 86 GT engine is blank. Hope this helps.
FWIW the 90 engine is a really good one.
Greg

 

[NolaBoy]

Thanks for all the leads. I try to take a look tomorrow to see if I see anymore stamping. I am interested to find out because as I look for parts I’m not sure what to ask for because I am not sure of the exact engine. As an example I’m swapping out my spark plugs now. The current plugs are Autolite AP45. I can’t find a Ford engine from 87 in that uses these. Any thoughts on this?


Sent from my iPhone using Tapatalk

 

[Broncobowsher]

Those take the big 13/16 socket. AP45 is an Autolite Platinum, size/heat range of 45. In short, the heads are older than your block. Your engine was rebuilt with parts from different engines. Old heads on new block. I recognize the plug number simply because I just came in from the garage and took out some Autolite 46 and put in AP46. The boat is a '61

I would have to dig around a little to see what the AP45s would be like. In general, if the plugs came out looking like they were running right, put the same plugs back in. Trying to remember where the casting numbers on the heads are at. That will help narrow down where the heads might have come from.

 

[Broncobowsher]

OK, just looked it up. A #46 Autolite plug is pretty much the standard spark plug. The 45 is a colder plug and the 124 is the coldest plug of that size. You want the 46 or AP46 plugs. From what I can tell, those heads are probably '74 and older.

 

[NolaBoy]

Ok. So, it sounds like the engine is a Frankenstein. Engine body from a 90 and heads from 74 or earlier.

One other question on the plugs. What’s the difference on the 45 and 46? The look similar in specs on the autolite guide. Also, should I go strait copper, or platinum/copper or platinum/platinum. (45, AP45, or APP45. or could use the 46 in place of these as well)

Thanks for the help!


Sent from my iPhone using Tapatalk

 

[ared77]

https://www.diyford.com/ford-cylinder-heads-valvetrain-interchange-small-block/

 

[oldiron]

To decode the heads....Remove the valve covers, look between cylinders 4-5 on the drivers side and 3-4 on the pass side, you should see an upside down set of casting numbers (probably an upside down "t" too). What are those numbers? It will be similar to the 0c24 type. It will at least narrow down what your working with. A picture will be helpful too.
Greg

 

[Broncobowsher]

Ok. So, it sounds like the engine is a Frankenstein. Engine body from a 90 and heads from 74 or earlier.

One other question on the plugs. What’s the difference on the 45 and 46? The look similar in specs on the autolite guide. Also, should I go strait copper, or platinum/copper or platinum/platinum. (45, AP45, or APP45. or could use the 46 in place of these as well)

Thanks for the help!


Sent from my iPhone using Tapatalk

A 45 is a hitter running plug. Tend to run cleaner than a colder plug like a 46. If you were running higher cylinder loads (spraying NS, running a blower) you go to a colder plug to keep from burning them up. My boat probably runs the colder plug because it spends it's life running full throttle a lot and for long periods of time. Since you have a 45 now, it appeared to work for you, run the 45 again.

The AP is a platinum tipped spark plug. APP is double platinum. The platinum is a premium plug that can last longer. When you hear of modern cars running 100k+ on a set of spark plugs, those are the platinum or iridium or some fancy rare metal electrode that avoids erosion. For a typical carburated application that will kill plugs due to deposits before erosion anyway, not really a benefit. Claims they last longer, run cleaner, make more power may be true but they are very minor and are not seen on the street, maybe in a lab. Claims an engine runs better are usually from just putting fresh clean plugs in more than anything else.

Now with that said, I found a set of AP plugs that were $5 more than the standard copper core for the whole set. For $5, sure I'll play. The boat doesn't get used much and the plugs I pulled out were 22 years old anyway. If the copper core lasted 22 years, I figure the next set of plugs will be needed about the time I retire. Not expecting anything more than what a standard plug will deliver, carburated fuel delivery from a 60 year old carburetor on a boat isn't exactly known as precise.