Spark plug woes

Nov 23, 2004
Hello All,

HELP! When I removed the r-side spark plug the spark plug and electrode came out, but the outer threaded section broke off just below the hex head...I tried using an east out but I can't get it to move. I thnk as the easy out digs in it is forcing the threads agains the cylinder head wall....Any Ideas? I can post a picture if that would help! I have never had this problem before!
Thank's John
Hi John,
It doesn't sound good. If that plug was in there stiff enough to break off during removal that threaded stub tube could be a real problem to get out. Hopefully it was because of rust and not that it was cross-threaded in previously. Try heating the area with a propane torch then use some penetrating oil, you may have to do this several different times allowing time for the penetrating oil to soak in.
The next thing you could try is to cut a trench or two in the tube with a Dremel tool and ball mill, hopefully you could somehow vacuum or blow the metal filings out of the cylinder afterward. You would have to be careful not to cut into the threads, but, at this point I'm wondering how healthy they are anyway.
The worst case scenario is that you have to pull the head, drill out the plug remains probably taking the plug threads with it, then you will have to install a helicoil.

justa thought,
Try heating the head up evenly...heating one side too hot, may cause warping.....then seat the easy out and do the threaded part with freezing spray,(Electronics shop) and give it a try. Pull the head if that easy out doesn't quickly do the deed and do the old bake oven heatup and try the spray again. Worse case is a hacksaw blade, cutting a slot in a couple of places just to where it starts to hit the threads and using a punch to try to get the section out from the inside of the head...either prepared to pay for a thread insert if it goofs up. That would be cheaper than paying for the damage of using a Dremel and getting the cylinder walls all trashed by the metal you won't be able to get out of the barrel again....
Instead of an "easy-out" try using a left hand threading tap of a size that will fit into the broken plug body, this will not spread the metal like an easy-out, the sharp teeth will dig in, and, being a left hand tap will bite in as you turn to unscrew the remains.Good luck, ride safely. James.
Wow, sounds ugly. Around here is a guy 'Jerry, The Disintigrator'. He lazers out broken taps, drill bits, easy outs etc. You might ask around in machine shops if there is someone local who can do it for you.
Last I knew Jerry was some where in Santa Ana, CA
HHHMMM.... I will try heating the head and using a reverse thread tap and using the freezing spay....But it looks like I will have to remove the head....RRRGGG. Is there any thing I need be aware of before I remove the head? This is my first Norton. I have a service manual on order and should see it in a couple days. Is there anyone in the Chicago area? Thanks for everyone's help.

Triple John
Norton heads come off easily, there are TEN fasteners holding the head on, be SURE you have all of them before trying to lift the head off, the one in the back is difficult to get to,other than that, no problem.
Getting the head back on takes some patience, be SURE to locate the push rods high into the head before placing it over the cylinders -- a helper comes in handy at this point, once positioned over the cylinders the pushrods can drop into place.Take your time and double check your work as you go.Let us know how get on. Good luck, ride safely. James.
Thank you for the tip! Can I remove the head while the engine is in the frame? Where can I get a head gasket?....Sorry for the simple questions, but I am new to a Norton......Kawasaki's I know after years of resto's, but not Norton...Not Yet!
head comes off in frame, if the head gasket is copper reuse it by annealling, eg heat to cheery red and allow it to cool or dunk in water, you dont have to heat it all at once, bit by bit will do if your heat source is small. The is a copy of the manual online to get you started, the link is on this forum so just do a search for manual.
I prefer composite head gaskets over the copper,Frank Holmes of Franks Brit Bike Barn in New Hampshire is a good source for all brit. bikes, he does high quality resto's. Ride safely/ James.
Triple John,

Expert Cycle (John Goodpaster) is a long time Norton wrench in (I believe) Hobart, Indiana. His number is 219-942-2351.

That being said, it is not difficult to pull the head in the frame. Get a shop manual and understand where ALL the head bolts are before you start. You will need a thin ring spanner for the nut between the carbs. Once it's loose, it's easier with two people to fish the push rods up into the head as far as they will go, then slide the head rearward and tilt. Once the pushrods are clear then bring the head out the primary side.

By the way, if you haven't already, check out the Chicago Norton Owners
OK...Head is off......Taking it off is really easy other than those pushrods.....Now before every one yells at me! I did not notice that the pushrods are different lenghts until I removed them RRRGGGHHH.. So when I go to reassemble are the longer ones on the outer side and shorter ones inboard? Also can anyone recommend where to get a gasket set? I saw one set on ebay with a starting bid of 20.00BP, can I get them locally? Also I found a guy here in Villa Park, Illinois that will use laser to burn the spark plug out. He said when he is finished the original threads will be intact and there will be no reason to use a heli coil!......Sweet I will let you all know how it works out!
Thank's for everyone's help!
The longer pushrods are in the middle and the shorter, exhaust, pushrods are outboard.

Use a good composite flame ring headgasket. Buy it from any of the Norvil suppliers (FairSpares, Old Britts, etc.).
I got here a little late. Anything you do to try to extract the broken part runs the risk of creating more grief than pulling the head.
With the head off, one of the above techniques should work, if not, then just drilling it out and fitting a solid insert, not a helicoil, will do it. I would (and did) install the inserts in both plug holes prophylactically ten years ago when I did the head for my Triumph, and will do it for my 74 Commando project. When fitting plugs, a little antiseize on the thread helps future, hassle-free removal, steel inserts or not.
Just in case

Since this is your first Norton as you mentioned, I will bet you are not guilty of this but the previous owner probably was.
What am I talking about?
The practice of some people lubricating spark plug threads with motor oil thinking they will come out easier next time.
What often happens is the oil will form a carbon deposit and make the plugs real darn tough to get out and, often enough, a broken spark plug is the result.
That and of course the over torquing of spark plugs.

Use a touch of anti-seize on the plug threads, go easy on the installation.
You can always tighten a loose plug, but as you well know now, you can't always loosen an overtightened plug.

Imagine, lasers for removing buggered up plugs!
Some darn fool will go and invent an electric starter next! hee,hee
Hello All,

I just dropped the head off at Witt Disintegrating in Addison Illinois. He said the original threads will remain intact with no damage to them at all. I will let you know how it looks. I hope to get the bike running in the next week or two...after 25 years of silence! Does anyone have or where can I get a copy of the owners (operators) manual? I have a weird problem with the ignition switch! With the ignition switch in the off position (no spark) the front and rear brake lights work, but with the ignition is in the on position(spark) the brake lights won't work. I am missing the left handle bar control, but I don't think it would matter...unless it has something to do with the missing kill switch? What do you all think?
Yes when I turn the key on I get a real nice spark from both coils, but the brake lights won't work? as soon as I turn the ignition off the brake lights work again? Is it possible the missing left bar control has something to do with it? .....BTW when you say turn the bike I assume mean the ignition? Because even when the ignition is off you can still turn all the lights on and actuate the horn!
Yeah, that is what I was asking. I am going to hazard a guess that the ignition switch is faulty. Try this. Remove the leads from the switch and jump them all together with male blade connectors daisy chained together, bypassing the ignition switch alltogether. This also makes a good tool for bikes for which you have no key or where the switch is questionable.
Hook up the wires in the harness and test the various functions. If all is good with the jumper but not with the switch, you have the culprit.
Is the ignition switch a simple two position switch...on & off? or is it an on off & accessories three position switch. Mine only has two positions.