News: Putting FUN and FRIENDLINESS, FIRST into owning and learning about AMC small bodied cars, primarily Eagles, Spirits and Concords as well as vehicles built in AMC's Mexican subsidiary, VAM.

The AMC Eaglepedia can now be accessed using the buttons found below  This is a comprehensive ever growing archive of information, tips, diagrams, manuals, etc. for the AMC Eagle and other small bodied AMC cars. 

Also a button is now available for our Face Book Group page.


Welcome to the AMC Eagles Nest.  A new site under "old" management -- so welcome to your new home for everything related to AMC Eagles, Spirits and Concords along with opportunities to interact with other AMC'ers.  This site will soon be evolving to look different than it has and we will be incorporating new features we hope you will find useful, entertaining and expand your AMC horizons.

You can now promote your topics at your favorite social media site by clicking on the appropriate icon (top upper right of the page) while viewing the topic you wish to promote.


  • November 21, 2024, 11:05:27 AM

Login with username, password and session length

Author Topic: cylinder head bolt clearance problem  (Read 2342 times)

0 Members and 1 Guest are viewing this topic.

Offline AMC1

  • Eagle Sport
  • ****
  • Posts: 326
  • Thumbs Up 8
cylinder head bolt clearance problem
« on: May 17, 2020, 12:15:55 PM »
I’m going to replace the 258 cylinder head gasket. There are 14 bolts & 12 seem to be ok in that I can fit a ½” drive - ¾” socket on them. The front & rear on the right side are a problem. I can only fit a 3/8“-¾” (slightly smaller circumference) on the front due to it being close to the casting. The rear one is impossible to get any socket on it at all, maybe 1/16” clearance. It also looks like the PO had the same problem. I can see smooth grinding marks inside the casting at the bolt but not on the bolt itself. He didn’t take off enough & I can understand that but I can’t figure how he got a socket on it unless he ground one down. I’m guessing that I’ll have to grind down a socket to fit. If I’m going to do that I would rather grind down a ½” drive rather than a 3/8”. I also use 12 point sockets but maybe I had better pick up a 6 pointer. Even then I may have to grind down one side to make it a five point socket, what chance do I have to break 85 lbs torque on a hex bolt with a five point socket. If I strip that bolt I’ll be up a creek. Am I the only one to see this problem?
1976 gremlin
pair of 1983 SX4's sports
1946 Cushman step-thru

Offline mudkicker715

  • Administrator
  • AMC Eagles Den Addicted
  • ******
  • Posts: 3037
  • Thumbs Up 167
Re: cylinder head bolt clearance problem
« Reply #1 on: May 17, 2020, 04:56:48 PM »
I have rebuilt many 258s. This is a first. Never had a problem or remember anything unusual  about head bolts.



Manitowoc WI

Offline djm3452004

  • Eagle
  • **
  • Posts: 137
  • Thumbs Up 18
Re: cylinder head bolt clearance problem
« Reply #2 on: May 17, 2020, 05:01:30 PM »
I’m going to replace the 258 cylinder head gasket. There are 14 bolts & 12 seem to be ok in that I can fit a ½” drive - ¾” socket on them. The front & rear on the right side are a problem. I can only fit a 3/8“-¾” (slightly smaller circumference) on the front due to it being close to the casting. The rear one is impossible to get any socket on it at all, maybe 1/16” clearance. It also looks like the PO had the same problem. I can see smooth grinding marks inside the casting at the bolt but not on the bolt itself. He didn’t take off enough & I can understand that but I can’t figure how he got a socket on it unless he ground one down. I’m guessing that I’ll have to grind down a socket to fit. If I’m going to do that I would rather grind down a ½” drive rather than a 3/8”. I also use 12 point sockets but maybe I had better pick up a 6 pointer. Even then I may have to grind down one side to make it a five point socket, what chance do I have to break 85 lbs torque on a hex bolt with a five point socket. If I strip that bolt I’ll be up a creek. Am I the only one to see this problem?



This is where a picture, if you could possibly post one please, would be worth the effort.  It's tough to diagnose or even comment on something like this without a visual...
Current Project: 1983 Eagle Wagon 258
Past AMC Project(s):  1979 Spirit Liftback 232
                                1968 Ambassador 287

Offline AMC1

  • Eagle Sport
  • ****
  • Posts: 326
  • Thumbs Up 8
Re: cylinder head bolt clearance problem
« Reply #3 on: May 18, 2020, 11:28:04 AM »
The bolts on the right side I'm sure aren't stock. They are plated. I don't recognize the head markings but they show 12-13 dots that look like a clock with a triangle in the center. I assume these are for setting a torque angle but the TSM doesn't mention torque angles - only torque values. Left side looks stock. The thing is that both sides use a 3/4" socket. Would you happen to know if 5'8" head bolt size was possibly stock and not 3/4". It's going to be a problem. I'll have to pull or at least release the hood off the car now to get deeper in there. 
1976 gremlin
pair of 1983 SX4's sports
1946 Cushman step-thru

 

SMF spam blocked by CleanTalk