[agear]

Since the engine came from just some guy I don't know what year the engine is. I have the 8I2CL03 stamped onto the side of my engine block. I'm trying to find out what the numbers mean. Anybody ?

 

[jpd1899]

Are you sure the second digit is an I and not a 1? Somebody on another posting site has the same number, Here is what they came up with.

Link to thread: http://www.pirate4x4.com/forum/showthread.php?t=650456
Then it could be 8(made in 1975) I2(december) C(258 2bbl) L(light block) 03( on the 3 day of december.

If you want to double check: http://webspace.webring.com/people/dg/geer_hed/cj_numbers.html#block

 

[1986cj]

I read it as December 3, 1988, C is a 258. The L not real sure about. Maybe Mopar added the L so they could tell if it was a from AMC or a 88 that they made. Just a guess on that one.

 

[agear]

Are you sure the second digit is an I and not a 1? Somebody on another posting site has the same number, Here is what they came up with.

Link to thread: http://www.pirate4x4.com/forum/showthread.php?t=650456
Then it could be 8(made in 1975) I2(december) C(258 2bbl) L(light block) 03( on the 3 day of december.

If you want to double check: http://webspace.webring.com/people/dg/geer_hed/cj_numbers.html#block

That's syncrhonistic because I ! posted that there a long time ago.
Well I went out to my jeep and on the drivers side I found this number EF 3235444
Which if I go here http://webspace.webring.com/people/dg/geer_hed/cj_numbers.html#block
The 3235444 says its from an 1981 - 1985 if they mean by 7/16ths head bolts they mean the studs with nuts on them in the heads.

 

[CSP]

By head bolts they mean the bolts that keep the head attached to the block.

 

[agear]

Trying to find a good exploded view of a 258. Are they all under the valve cover ?

 

[CSP]

Some are under(#26 below), some are outside of the valve cover (#9 below), as they are on just about any overhead valve engine.

Google images for any picture you want to see.

 

[ctm]

because it is 7 digits that is a YJ block made Dec 3, 1988, the 4th and 5th digit letter code "CL" is listed in the YJ FSM as "engine type/fuel system/compression ratio" but it does not list what the various letter codes designate.

 

[agear]

Really ? Where did you see that if it was 7 digits it's a yj block ? Where are the head and crankshaft casting numbers found ?

 

[5-90]

I read it as December 3, 1988, C is a 258. The L not real sure about. Maybe Mopar added the L so they could tell if it was a from AMC or a 88 that they made. Just a guess on that one.

That would be unnecessary - 1987-early 1988 6-242 blocks have the AMC logo as a casting mark, late 1988-up 6-242 block have the Chrysler pentastar logo...

 

[agear]

Well like I said i have this on the drivers side of the engine block -EF 3235444 . And if you go here http://webspace.webring.com/people/dg/geer_hed/cj_numbers.html#block it reads it could be an amc from 1981-1985 258 4.2 3.75 L-6 7/16" Head Bolts or the next one reads it could be an amc from 1986
258 4.2 3.75 L-6 1/2" Head Bolts or the last one reads it could be an amc from 1987-1989 258 4.2 3.75 L-6 2.06" Crank Neck, Spec. if Alum. or Plastic Valve Cover, 1/2" Head Bolts

Now in the pictures i've attatched you'll see the bolt (or stud) I checked the diameter of . It was 7/16ths
so what do you think ?

 

[agear]

To confuse you a little more. Supposedly the head is from a different year.

 

[1986cj]

5-90 Do you mean a 258 or a 242 block had the logo?

 

[5-90]

Well like I said i have this on the drivers side of the engine block -EF 3235444 . And if you go here http://webspace.webring.com/people/dg/geer_hed/cj_numbers.html#block it reads it could be an amc from 1981-1985 258 4.2 3.75 L-6 7/16" Head Bolts or the next one reads it could be an amc from 1986
258 4.2 3.75 L-6 1/2" Head Bolts or the last one reads it could be an amc from 1987-1989 258 4.2 3.75 L-6 2.06" Crank Neck, Spec. if Alum. or Plastic Valve Cover, 1/2" Head Bolts

Now in the pictures i've attatched you'll see the bolt (or stud) I checked the diameter of . It was 7/16ths
so what do you think ?

The top of those studs is usually threaded 7/16" - the underside can be either 7/16" (early, probably before 1975) or 1/2" (late, and definitely on the 6-242) - SAE Coarse in all cases.

I know the 6-242 blocks had the logo changed, so I see no reason to suspect that the 6-258 had it changed as well (I've also seen AMC V8-360 blocks in SJs in late 1988-1991 that had the pentastar logo as well. It's a simple change to effect in the moulds, so there's no reason to not do it across the board. The 4-150, I'm sure, did the same thing as well.)

 

[agear]

im confused . I did not see any star or any logo so far.

 

[agear]

5-90 typed "The top of those studs is usually threaded 7/16" - the underside can be either 7/16" (early, probably before 1975) or 1/2" (late, and definitely on the 6-242) - SAE Coarse in all cases"

5-90 You just had to tell me that didn't you :laughkidding)
But I think it's a 258

 

[1986cj]

Ruling out a 242 should be easy, Does the block you have a place to mount a mechanical fuel pump? I don't think a 4.0 (242) had the opening or mounting boss in them.

 

[agear]

Yes, it has a mechanical fuel pump.

 

[CSP]

The top of those studs is usually threaded 7/16" - the underside can be either 7/16" (early, probably before 1975) or 1/2" (late, and definitely on the 6-242) - SAE Coarse in all cases.

The only blocks with 1/2" head bolt holes were '81-85. Anything older or newer than those years was 7/16".

 

[keith460]

The only blocks with 1/2" head bolt holes were '81-85. Anything older or newer than those years was 7/16".

Not so, it is just the opposite. 81-85 have 7/16" head bolts. late in 1985 the head bolts got changed over to 1/2" for the 1986 model year and beyond.
1975-79 head bolts were 1/2" also. 1980 was a bastard year, either 7/16' or 1/2".