Forum Home Forum Home > CJ-2A Discussion Area > How to information
  New Posts New Posts RSS Feed - Spark Plug Removal
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Spark Plug Removal

 Post Reply Post Reply
Author
Message
Snojetter View Drop Down
Member
Member


Joined: 23 Aug. 2018
Location: Brandon, MN
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote Snojetter Quote  Post ReplyReply Direct Link To This Post Topic: Spark Plug Removal
    Posted: 23 Aug. 2018 at 10:43pm
Hi folks - new guy here.  The topic title might lead you to believe I've never held a wrench before...but I've pulled a plug or two in my time. Anyway, I've got a '46 CJ-2A that's been sitting in dry storage for quite some time - 5 or 6 years I'd say.  I went to it the other day just to tinker.  I noticed there was some crud build up around the plug, so I blew off the junk and decided to remove the plugs and see what they looked like.  I loosened #1 enough that I could spin it by hand...but I soon noticed that it wasn't actually un-threading.  It was just spinning in the head.  The ceramic is not loose from the body (which I've seen happen before).  This plug just spins without being able to remove it.

I find it hard to believe that the threads are stripped, but even if the threads are buggered, I would still think it would climb up and out on whatever threads are left.  If I try to exert "up" pressure and spin, it still won't come out.  I can turn it left or right and it just spins - no tightening, no loosening.  What could be holding this thing in place?  If the threads are shot, it should just pull out.  If there's some bit of thread left, it should walk up and out with some level of effort.

I assume I'll have to pull the head to get this plug out.  I'm just curious is anybody has ever experienced this before?  It's a new one to me.
Kyle Sands <>< Brandon, MN
1946 CJ-2a
Back to Top
Unkamonkey View Drop Down
Member
Member


Joined: 23 Mar. 2016
Location: Greeley CO
Status: Offline
Points: 1865
Post Options Post Options   Thanks (0) Thanks(0)   Quote Unkamonkey Quote  Post ReplyReply Direct Link To This Post Posted: 24 Aug. 2018 at 12:40am
Very interesting, I have never heard of that. I had a '64 VW that the number 3 spark plug would on occasion decide to send one off into space. you probably should check into Helicoills.
uncamonkey
Back to Top
cpt logger View Drop Down
Member
Member


Joined: 23 Sep. 2012
Location: Western Colorad
Status: Offline
Points: 1322
Post Options Post Options   Thanks (0) Thanks(0)   Quote cpt logger Quote  Post ReplyReply Direct Link To This Post Posted: 24 Aug. 2018 at 12:52pm
I have seen a few where someone installed a spark plug that was the wrong length. In other words, the threaded section was too long. The treads sticking into the combustion chamber collected a carbon coating. When the mechanic tried to remove the plug it would turn about 1/4 turn, but the carbon would not allow the plug to come out. The mechanic then forced the issue & stripped the threads.

I suspect that this may be your problem. If so, your best bet is to pull the head. Then, after removing the spark plug, Heli-Coil that spark plug hole . 

I would never admit this out loud, but I may have done that & instead of fixing it right then, I may have just driven the rig until the spark plug blew out of the aluminum head.Embarrassed I do not recommend that approach. However, I found another Heli-coil like repair kit & was able to fix the head without pulling it. Thumbs Up 
Back to Top
Ol' Unreliable View Drop Down
Member
Member
Avatar

Joined: 25 Sep. 2016
Location: CO Springs CO
Status: Offline
Points: 2514
Post Options Post Options   Thanks (0) Thanks(0)   Quote Ol' Unreliable Quote  Post ReplyReply Direct Link To This Post Posted: 24 Aug. 2018 at 9:53pm
Welcome to the page, Snojetter!
There's a reason it's called Ol' Unreliable
Back to Top
Snojetter View Drop Down
Member
Member


Joined: 23 Aug. 2018
Location: Brandon, MN
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote Snojetter Quote  Post ReplyReply Direct Link To This Post Posted: 27 Aug. 2018 at 10:07pm
That sounds like a plausible explanation.  I suppose I'll find out when I pull the head.  If I did strip the threads, they were pretty weak.  I didn't put much torque on the wrench except to break it loose.  After that initial force to get it turning, I didn't meet any unexpected resistance - that initial turn to crack the plug loose must have stripped the threads.

I've had this Jeep for almost 25 years and the plugs are ones I installed back in the 90's - Champion J8C's.  I thought those were the correct size...but who knows.  I was a foolish teenager back then.
Kyle Sands <>< Brandon, MN
1946 CJ-2a
Back to Top
JeepFever View Drop Down
Member
Member
Avatar
Sponsor Member

Joined: 07 Aug. 2012
Location: VA
Status: Offline
Points: 1449
Post Options Post Options   Thanks (0) Thanks(0)   Quote JeepFever Quote  Post ReplyReply Direct Link To This Post Posted: 28 Aug. 2018 at 12:20am
I did not reply on original question,  because I have no answers.  Confused
 
Welcome to forum,  hopefully a simple fix,   . . .  but seems scary.  Smile
Back to Top
48willys View Drop Down
Member
Member


Joined: 22 June 2007
Location: sw/ virginia
Status: Offline
Points: 805
Post Options Post Options   Thanks (0) Thanks(0)   Quote 48willys Quote  Post ReplyReply Direct Link To This Post Posted: 28 Aug. 2018 at 7:56am
It does seem odd, a j8c should be short enough to not get buildup on it. I have had them break off at the base and the porcelain holds it together, bad thing about that is the porcelain tip can break off and drop into the cylinder.
1946 cj2a #28680
1948 chevy 3800 thriftmaster
1946-50's cj2a-3a farm jeep
1993 yj, aka the yj7
Back to Top
Ol' Unreliable View Drop Down
Member
Member
Avatar

Joined: 25 Sep. 2016
Location: CO Springs CO
Status: Offline
Points: 2514
Post Options Post Options   Thanks (0) Thanks(0)   Quote Ol' Unreliable Quote  Post ReplyReply Direct Link To This Post Posted: 30 Aug. 2018 at 12:18am
A J8C is the correct Champion plug. 
There's a reason it's called Ol' Unreliable
Back to Top
Oilleaker1 View Drop Down
Member
Member


Joined: 06 Sep. 2011
Location: Black Hills, SD
Status: Offline
Points: 3840
Post Options Post Options   Thanks (0) Thanks(0)   Quote Oilleaker1 Quote  Post ReplyReply Direct Link To This Post Posted: 02 Sep. 2018 at 6:48am
Cast iron is much softer than a steel spark plug, so your head most likely suffered. I think there is a kit to install a slug or wider/better fix than a heli coil. I'd do some more research before you jump. Another head would also be a option. Maybe it's time to upgrade to a Supersonic , higher compression head? 10 more HP would sure be a bunch in a old Jeep. Oilly
Green Disease, Jeeps, Old Iron!
Back to Top
Greaser007 View Drop Down
Member
Member
Avatar

Joined: 16 Jan. 2018
Location: Anderson, Calif
Status: Offline
Points: 181
Post Options Post Options   Thanks (0) Thanks(0)   Quote Greaser007 Quote  Post ReplyReply Direct Link To This Post Posted: 21 Sep. 2018 at 9:16pm
So then, once the head is removed, how is the plug extracted without breaking the head ?

Is it safe to break out the porcelain and blow the plug out with a torch ?

Then chase the threads and Heli-Coil if necessary ?

I haven't been faced with this dilemma yet ?

Just the other day, I was reading an ad for an L134 which said the Plugs needed to be Extracted !   And it was a coastal engine. Hmm could be a similar dilemma.

Edited by Greaser007 - 21 Sep. 2018 at 9:22pm
Back to Top
DonH View Drop Down
Member
Member


Joined: 12 Feb. 2006
Location: Central Massachusetts USA
Status: Offline
Points: 106
Post Options Post Options   Thanks (0) Thanks(0)   Quote DonH Quote  Post ReplyReply Direct Link To This Post Posted: 22 Sep. 2018 at 12:47am
This has not happened to me. That said, you will have to remove the head and see what it looks like inside. I am thinking that you might be able to apply enough pressure to the plug from the inside to allow it to be turned out on whatever threads remain. Beyond that removing the porcelain and drilling would be my next choice with the goal of limiting the damage to the plug itself, the same removing a broken stud  or bolt.

Good luck to you,

DonH
1946CJ2A
Back to Top
3A Steve View Drop Down
Member
Member


Joined: 10 June 2016
Location: West Virginia
Status: Offline
Points: 308
Post Options Post Options   Thanks (0) Thanks(0)   Quote 3A Steve Quote  Post ReplyReply Direct Link To This Post Posted: 20 Oct. 2018 at 5:24pm
Bought a rotted 3A when the thought hit me that I needed to repeat years ago experiences with a 47 2A. Ended up throwing most things away and selling anything useful. The engine appeared to be seized (it wasn't and someone who bought it for the crank found it better than the engine they had) and there was one spark plug I couldn't get out. It was sitting higher than the others. Have since been told that people used to do that when their engines were burning oil and they would put an extra bolt/nut in to get the plug to sit higher. Anyway, took it to a machine shop that does engine rebuilds for Kaiser (at least that is what they said... and they did have a long row of 134's on the shop floor). Cost $140 to have the plug pulled and the head resurfaced. The rebuilt head is one of the last parts left, just in case the current 3A needs one in the future.
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.00
Copyright ©2001-2018 Web Wiz Ltd.