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Author Topic: Main plug removal  (Read 7536 times)

Hugh Conway

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Main plug removal
« on: December 06, 2014, 11:46:53 PM »
Sorry gents, I am still having an issue here. For history see my thread COV WTF  here..... http://listerengine.com/smf/index.php?topic=7294.0

The main plug as installed in the head is a different  concave shape than that used with a standard COV or a blanking plug as used in 8/1s and Listeroids.

I have a replacement main plug of the proper shape, but am unable to remove the old one.

Tried the "drive in a hardwood  plug, reinstall the COV with the handwheel screwed out a bit, the main plug will be ejected by the force of compression"
  That method proved unsuccessful

Also reluctantly tried the alternative to be used if the hardwood plug method was unsuccessful: "Tap the hole in the main plug and use a bolt to draw it out"
 Insufficient thread caused the bolt to pull out. Tried with larger bolt, same result. Drilled and tapped larger still  (1/2"  bolt) ....that should do it.....
 Also unsuccessful.

So I think to return to a version of the hardwood plug method........ reinstalled the 1/2" bolt, screw in the blanking plug,  try to START the engine.......lots more compression pressure when the engine actually fires off, I am thinking.
Started the engine, let it fire a few times, but the #%$@+%! main plug is still in there fast, and now must be replaced because I have drilled out and threaded it!

As you know, I am in a remote area with limited resources. This probably needs to be machined out, but my machine shop consists of a selection of hammers and files.

Now what? anyone care to recommend an different approach? Will I have to pull the head and get the plug machined out as a last resort?

As usual, all suggestions welcomed.

Cheers,
Hugh
JKson 6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1978 Royal Enfield (glutton for punishment by Indian iron)
1963 BMW R-27 project

Thob

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Re: Main plug removal
« Reply #1 on: December 07, 2014, 02:07:42 AM »
Do you have a welding machine or torch?

You can try welding the threaded rod to the plug and then pulling it out.  Or try heating the plug with a torch.  Often times, heat will expand a plug (or busted stud, etc.) enough to compress any rust or carbon on the outside of the part you're trying to remove.  Once it cools, try pulling it out again.

Otherwise, it's a bunch of drilling, filing and hammering to get it out - or remove the head and make a trip to the machine shop.

You might also try drilling the hole out to about 1/2" or more, then using a hacksaw blade to cut thru the plug in two or more directions, then collapse the plug and pull it out.  The trick is to ONLY cut the plug, not the head!
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dieselgman

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Re: Main plug removal
« Reply #2 on: December 07, 2014, 02:37:43 AM »
It sounds to me like you have the plug secured in place with carbon (maybe a little rust as well).
Heat is the usual best method to soften carbon and cause it to release... this is about the only non-destructive way to get certain fuel injector nozzles out of their holders and we do that all the time here with a little propane torch.
I think I would go at it with a pencil torch, just a little at a time until the plug will let go.

dieselgman
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Horsepoor

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Re: Main plug removal
« Reply #3 on: December 07, 2014, 04:00:23 AM »
Because you are in a remote place, and may not have access to a torch or wedler: I offer this thought as a possibility. Now this crude but you will probably have these parts on hand.

Cut a bolt to such a length so that you can insert into the existing hole, into the combustion chamber and then pull it back turning it sideways.

Now you probably have some chain laying around. Get a piece of small chain, say 6 to 10 inches. Make sure the bolt will fit through the end link. This with give you a T bolt with a piece of chain hanging out of the head.

From here you might be able to attach a puller to the chain, if you have one. Or you might be able to wrap it around a pry bar and lever it out. Or you might wrap it around some sort of iron bar and pound wood wedges under each side of the bar until the plug brakes free.

Now I know these are crude suggestions, but it sounds like you need some out the box suggestions to this problem
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Hugh Conway

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Re: Main plug removal
« Reply #4 on: December 07, 2014, 06:03:53 PM »
Thanks for these good ideas.
I'll give them a try with the easiest first.
Heat the plug as Gary suggests.
I do have a torch, but not a welding rig.
The hacksaw method......have done that several times in other situations, though here it would be a last resort. Risk adverse in buggering up the head!
The chain method.....worked very well in pulling the flywheel on my SR2. Do not mind "crude but effective" solutions so long as nothing important gets damaged. Not sure I can fit a chain link into the plug.
I will go down the list of suggestions until with your help, I succeed.
Will keep you posted, and if there are more ideas forthcoming, I am all ears.
Cheers,
Hugh

JKson 6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1978 Royal Enfield (glutton for punishment by Indian iron)
1963 BMW R-27 project

bschwartz

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Re: Main plug removal
« Reply #5 on: December 10, 2014, 04:27:54 AM »
Question......  With your attempt:

...So I think to return to a version of the hardwood plug method........ reinstalled the 1/2" bolt, screw in the blanking plug,  try to START the engine.......lots more compression pressure when the engine actually fires off, I am thinking.
Started the engine, let it fire a few times, but the #%$@+%! main plug is still in there fast, and now must be replaced because I have drilled out and threaded it!

Did you leave the outer section loose?  ie. leaving enough room between the blanking plug and COV to allow it to move?  Did you remove the screw section of the COV to allow space for the air to be pushed out when the plug does move?

Did this make any sense?  It is what I had to do to remove a stuck plug. 
If necessary, I can draw (poorly) a picture.

NOTE:  I didn't screw the COV section in quite enought threads, and when the blanking plug SHOT out, it hit my garage door leaving a nice dent.
-Brett

1982 300SD, 1995 Suburban 6.5, 1994 F250, R170, Metro 6/ sold :( , Witte CD-12 ..... What else can I run on WVO?

dieselgman

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Re: Main plug removal
« Reply #6 on: December 10, 2014, 04:32:20 AM »
Glad you weren't standing there at that point in time Brett!  :o

dieselgman
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bschwartz

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Re: Main plug removal
« Reply #7 on: December 10, 2014, 02:09:29 PM »
I'm glad you can't hand crank an engine, turn on fuel, and flip the decompression lever WHILE standing in front of the plug  ::)
-Brett

1982 300SD, 1995 Suburban 6.5, 1994 F250, R170, Metro 6/ sold :( , Witte CD-12 ..... What else can I run on WVO?

dieselgman

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Re: Main plug removal
« Reply #8 on: December 10, 2014, 02:11:41 PM »
Now that would be some real talent!  :laugh:

dieselgman
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Lyons Kansas warehousing and rebuild operations

Hugh Conway

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Re: Main plug removal
« Reply #9 on: December 10, 2014, 05:47:30 PM »
Question......  With your attempt:

Did you leave the outer section loose?  ie. leaving enough room between the blanking plug and COV to allow it to move?  Did you remove the screw section of the COV to allow space for the air to be pushed out when the plug does move?

Did this make any sense?  It is what I had to do to remove a stuck plug. 
If necessary, I can draw (poorly) a picture.

NOTE:  I didn't screw the COV section in quite enought threads, and when the blanking plug SHOT out, it hit my garage door leaving a nice dent.

Good morning Brett
Yes, I did leave a gap between the bolt and the blanking plug. No Joy. I thought I might try without the blanking plug........what the hell, the (hopefully) projectile main plug would at worst ricochet off the rock bluff about 30 feet away and be lost in the forest.
Fired it up........plug still there, stuck as stuck can be.
A couple of days ago, tried the torch with propane, then with hotter MAPP gas. Got the plug to a dull red on a dark day. Still stuck tight, though have not had the opportunity to try loosening it after cooling down.
We have been in the midst of a wave of storms here for the past 3 days. Trees breaking and 3 meter seas, heavy rainfall. We will be having lots of clean-up work and checking on our client's properties when this blows itself out.
Cheers,
Hugh
JKson 6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1978 Royal Enfield (glutton for punishment by Indian iron)
1963 BMW R-27 project

bschwartz

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Re: Main plug removal
« Reply #10 on: December 10, 2014, 05:51:55 PM »
You could always try again and put the engine under load to increase cylinder pressure, maybe that would work....
-Brett

1982 300SD, 1995 Suburban 6.5, 1994 F250, R170, Metro 6/ sold :( , Witte CD-12 ..... What else can I run on WVO?

Tom

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Re: Main plug removal
« Reply #11 on: December 10, 2014, 06:03:03 PM »
Also a good load it may come loose when it warms up.
Tom
2004 Ashwamegh 6/1 #217 - ST5 just over 3k hours.

Hugh Conway

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Re: Main plug removal
« Reply #12 on: December 10, 2014, 06:35:32 PM »
You could always try again and put the engine under load to increase cylinder pressure, maybe that would work....

Good thought Brett and Tom. The project is not that far along yet. Not belted up to a generator, no mount fabbed, etc.

Cheers,
Hugh
JKson 6/1  (Utterpower PMG ) Off-grid
Lister 6/1 Start-O-Matic engine......running with PMG
1978 Royal Enfield (glutton for punishment by Indian iron)
1963 BMW R-27 project