head bolt question - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 10-25-2002, 09:02 PM
Posts: n/a
head bolt question

I have a question about a 4.2L cylinder head.
I was originally going to use arp head bolts for this motor, but I have 7/16" bolts and the arp head bolt kit is 1/2" and that is the only one they offer.

Well I am reusing the stock bolts. There are a total of 14 bolts and 7 shorts which go to the distributor side. and 4 long bolts and 4 long bolts with studs on top. I need to know where the bolts with the studs go? The engine was disassembled when I got it therefore I did not disassemble it or I would know where they went. Also what bracketry do they hold?
Sponsored Links
post #2 of (permalink) Old 10-25-2002, 09:58 PM
Join Date: Sep 1999
Posts: 2,137
Thanks: 0
Thanked 0 Times in 0 Posts
Re: head bolt question

It's a mystery...
They don't hold a dang thing that I know of.
Usually they are on the manifold (driver's) side.

FYI: You can re-use 4.2 head bolts but should never re-use 4.0 bolts ... all to do with tinsel strenght, stretch, and such ... from what I've been told ...
Jaffer is offline  
post #3 of (permalink) Old 10-25-2002, 10:40 PM
Join Date: Jun 2001
Posts: 1,628
Thanks: 0
Thanked 0 Times in 0 Posts
Re: head bolt question

</font><blockquote><font class="small">In reply to:</font><hr />
They don't hold a dang thing that I know of.

[/ QUOTE ]

They hold the valve cover on. If you have the stock plaastic valve cover, there should be cutouts on the driver side for the studed head bolts. There are little wash/nut combo things that screw on the studs and hold the valve cover on.
dschwab9 is offline  
Sponsored Links
post #4 of (permalink) Old 10-25-2002, 10:50 PM
Posts: n/a
Re: head bolt question

ARP does make the 7/16 set [img]images/graemlins/smile.gif[/img]. I know that Clifford sells them. Taken from their website; 22-3043 AMC 7/16" Dia. 1 (7 Long, 7 )

post #5 of (permalink) Old 10-25-2002, 11:08 PM
Official Curmudgeon
CJ7Taz's Avatar
Join Date: Nov 2001
Location: Kansas
Posts: 4,705
Thanks: 2
Thanked 5 Times in 5 Posts
Re: head bolt question

The early engines used 1/2" the later engines used 7/16". My '80 had 1/2" the '83 I replaced it with had 7/16".

I don't remember, the bolts with the stud on the top hold something optional, possibly an A/C compressor. Both my engines only had one and it didn't have a purpose. There used to be people asking for on of the studded bolts here regularly, I think to add onboard air.
CJ7Taz is offline  
post #6 of (permalink) Old 10-25-2002, 11:12 PM
Posts: n/a
Re: head bolt question

Arp makes 7/16" bolts that will fit the amc 258 but show only 1 part number or kit that is available for the 258. You can call them with the lengths of the bolts and they will sell you 14 bolts but there is no kit. I guess clifford put one together. I spent 35 minutes on the phone with ARP today. The kit number is 112-3106. The only reason that I did not order the 7/16" bolts was due to the to the fact I was unsure of what the bolts with the stud on top were for and arp does not make those. But now that I know what they are for..... I did however to make sure do a extensive search on their website with your part number to make sure and they had no part number that matched that all of their part numbers are 7 digits ex. xxx-xxxx . Here is their headbolt catalog link:
post #7 of (permalink) Old 10-25-2002, 11:50 PM
Posts: n/a
Re: head bolt question

Okay on my 258 which according to the engine serial # is an 81, I know for a fact it has 7/16" head bolts but know nothing about It's history. The bolts doen the intake side of the head are as fallows: stud, stud, stud, bolt, bolt, stud, bolt. The front 2 studs are used to hold and aluminum braket that holds a ideler for a stock AC system. The other 2 studs are not used on my engine and I am not sure of the purpose.

Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome