AMC 258 Engine/Head ID help

[SaltyNole]

I am looking for a little engine/head ID help.

Looks like the PO swapped out the engine in the '81 Jeep CJ I just bought. I also would not put it past Jeep to have dropped in a left over engine from 1980.

What made me notice is the valve cover gasket I bought for the '81 model is straight on the passenger side. However, my head and valve cover both have some curved cut outs at each spark plug.

This started my research on engine and head casting/stamping numbers.

My engine block has a stamping code of 003C04 on the passenger side and casting code of 3235077 on the driver side. In my research, I have seen mixed information on this stamp code, but there is some information that shows this being a AMC 258 i6 / 4.2l block that was manufactured in March 4, 1980.

The casting code also indicates that this is a 1980 AMC 258 i6 / 4.2l block.

I also looked at the head casting code since the valve cover had to come off and that code is 3227258-2. Again from what I am seeing this is a head that was used on the 1980 AMC 258 i6 / 4.2l blocks and prior. However, it seems that only in 1980, the temp. sending unit was at the top rear of the head, and that is where mine is.

I hope someone has a little better insight than I do on this subject and can enlighten me a bit more. Otherwise I will assume I am correct in my assumption this is a 1980 model AMC 258 i6 / 4.2l with a 1980 model head.

 

[Jimbos76cj]

How many bolts does it use? post up a pick of th evalve cover.. And just to ask, is there any thing your looking to do to the motor other then change the valve cover gasket? My 89 YJ uses rear brake hard ware from a 80 CJ fwiw.. Jeeps tend to be a mix match.

 

[mtnwhlr]

Both the '83 and '84 I have are straight across the pass. side

 

[73CJ]

Based on your casting numbers - 80 AMC 258 i6 / 4.2l

Jeep CJ VIN / Casting / Production Numbers

Also check the VIN code on the tub. That will tell you what it left the factory with.

 

[SaltyNole]

Jimbos76cj

The valve cover has 2 bolts on the driver side, 3 on the passenger side and one on each end. Looks to be the same exact pattern for the 1981 and later head, just with the curved edge versus the straight edge. Pictures posted. It is also a metal cover, which I understand was changed to plastic in '81.

I plan on doing lots more, but I am focused on stopping the leaking and whats not working at the moment. The engine looks a gunky, but seems to be running really good. No smoking, no knocking or other weird noise, no oil in water or water in oil. No leaking either, other than the valve cover. Doing a Transmission swap at the moment. There are some steering issues as well.

73CJ

The VIN indicates AMC 258 i6 / 4.2l , but I could tell the engine had been pulled and worked on. I thought it was just rebuilt, but it could have been replaced.

I think I am going to go with 1980 AMC 258 i6 / 4.2l until another incorrect park proves me wrong.

 

[SCSEAJAYSEVEN]

My '78 AMC 258 i6 / 4.2l has that same valve cover in my CJ7 .
Fel-pro part # VS 50258 C or VS 50186 C should work for you. About 22 foot lbs. torque on each cover bolt..


SCSEAJAYSEVEN

 

[SaltyNole]

SCSEAJAYSEVEN, thank you.

I looked at the FEL-VS50258C and it is the right one, even though it did not cross reference to an '80 or '81 AMC 258 i6 / 4.2l .

You have to love trying to figure out parts on a Jeep.