Tight spark plugs

[devo]

Just took a plug out of the bike to check colour and had quite a worry undoing it as it got quite tight as I was backing it out.
Got it out without damaging the thread but there was obvious carbon on the bottom 3 threads.
It is definitely the correct plug so was wondering if it would be ok to use a bit of nickel anti-seize when putting it back to avoid this problem next time, The plugs hadnt been out for at least 15K that I know of.

 

[otherwise]

Carbon on 3 threads, hmmm, I think I'd put double washers onto the plugs when replacing.
Anti-seize is always a good idea.

 

[devo]

cheers Kevin
I double checked the part no as well cos I was thinking it may be too long a reach but it is the right no.
Will double washers still seal ok ?

 

[DaveM]

Was the other plug ok Harry

 

[otherwise]

cheers Kevin
I double checked the part no as well cos I was thinking it may be too long a reach but it is the right no.
Will double washers still seal ok ?

They should seal, I'd be game enough to give it a go. You have to use a bit of common sence, put two on, screw them down and then take them off and inspect how the crush woked out. If you don't like the idea just stick with what you had and take them out more often.

 

[devo]

Was the other plug ok Harry

Yes Dave, the second one was as bad as the first.
colour on the plug was good as gold,but definately 3 threads too long in the reach.When it got tight I would wind it back in a bit and then carry on out.It was a worrying time but,I was sure at times I was going to strip out the thread in the head.

They should seal, I'd be game enough to give it a go. You have to use a bit of common sence, put two on, screw them down and then take them off and inspect how the crush woked out. If you don't like the idea just stick with what you had and take them out more often.

Cheers Kev,I'll give it a go and if all else fails I'll just inspect them a bit more often.I am picking however that the anti seize will help.

 

[DaveM]

I must then remember to check mine then as I would hate to strip them as that becomes a mission. Been there and know all about it

 

[Sea Dog]

Hey Harry.

Had the same issue with the TSS. Added a copper washer of the appropriate thickness, used anti seize grease and problem solved.

In other words.....I agree with Kevin.

 

[Doug]

Sounds odd, if it's the right plug it shouldn't protrude that much into the combustion chamber.
Be careful about using extra crush washers,more than half of the heat absorbed by the insulator nose is transferred into the head via that washer so any change to that heat path will effectively alter the heat range of the plug.
A good high temperature anti-sieze compound such as copperslip will certainly help but again,be careful.
The lubricating effect of the compound will affect the apparent tightening torque so take care not to over-tighten.

 

[Rocky]

Sounds odd, if it's the right plug it shouldn't protrude that much into the combustion chamber.
Be careful about using extra crush washers,more than half of the heat absorbed by the insulator nose is transferred into the head via that washer so any change to that heat path will effectively alter the heat range of the plug.
A good high temperature anti-sieze compound such as copperslip will certainly help but again,be careful.
The lubricating effect of the compound will affect the apparent tightening torque so take care not to over-tighten.

Good advice
I seem to recall reading on the NGK web site to not use anti-seize on their plugs because the threads are coated to prevent seizure in the head.
I don't know when they started doing that, but I've been using a very light smear of anti-seize on the threads of my plugs for years. The package the NGK plugs come in doesn't say not to use it.

 

[CarlS]

Good information, Doug. Thanks.

 

[Rocky]

FWIW, here's the bulletin from NGK.
http://www.ngksparkplugs.com/pdf/TB-0630111antisieze.pdf

 

[CarlS]

Excellent information, Rocky. Good post.

 

[devo]

Thanks for all the response and info guys.
My query also was about the choice of anti-seize.
I have both copper and nickel, but I,ve always been of the belief that you dont put copper and ali together or you will get electrolysis.

 

[otherwise]

Doug said,
"Be careful about using extra crush washers, more than half of the heat absorbed by the insulator nose is transferred into the head via that washer so any change to that heat path will effectively alter the heat range of the plug."
I think this is probably correct in theory. I'm a practical person and for normal riding situations double thickness washers wouldn't worry me at all.

 

[Sea Dog]

FWIW, here's the bulletin from NGK.
http://www.ngksparkplugs.com/pdf/TB-0630111antisieze.pdf

Good information. Regardless if you do or do not use anti seize, using a torque wrench is a must when working with aluminium threads.

 

[devo]

OK to update,I couldnt lay my hands on a new set of plugs today so I have reinstalled the old ones(without anti seize as I am still not sure on the copper or nickel choice ) and it is running fine.Even tho I suspect they are the original plugs with 28k on them,apart from being 2 though tight ( which makes me think they were under gapped from new ) they appeared to be in perfect nick and showing good colour.I will try to pick up a new set tomorrow at another outlet or I will pick some up when I head into the city next week.

I must then remember to check mine then as I would hate to strip them as that becomes a mission. Been there and know all about it

I did the job with the tank in place, but I can honestly recommend removing it for ease of access and piece of mind.If you are still running the AI this would be a must.

 

[Doug]

Otherwise,you're probably quite right that under everyday circumstances it wont make a significant difference.It's just that having been in the spark plug industry years ago I tend to be a bit sensitised to this sort of thing.
As regards tightening torque,a good rule of thumb is that with a new crush washer,finger tight plus a quarter turn(90degrees)
If the washer has been tightened before,then one eighth of a turn(45deg.)
Most people over-tighten them,contrary to some beliefs,they don't hold the head on and I've personally never seen one come out by itself!

 

[CarlS]

Otherwise,you're probably quite right that under everyday circumstances it wont make a significant difference.It's just that having been in the spark plug industry years ago I tend to be a bit sensitised to this sort of thing.
As regards tightening torque,a good rule of thumb is that with a new crush washer,finger tight plus a quarter turn(90degrees)
If the washer has been tightened before,then one eighth of a turn(45deg.)
Most people over-tighten them,contrary to some beliefs,they don't hold the head on and I've personally never seen one come out by itself!

You are spot on.

 

[otherwise]

Otherwise,you're probably quite right that under everyday circumstances it wont make a significant difference.It's just that having been in the spark plug industry years ago I tend to be a bit sensitised to this sort of thing.
As regards tightening torque,a good rule of thumb is that with a new crush washer,finger tight plus a quarter turn(90degrees)
If the washer has been tightened before,then one eighth of a turn(45deg.)
Most people over-tighten them,contrary to some beliefs,they don't hold the head on and I've personally never seen one come out by itself!

Quote,
"contrary to some beliefs,they don't hold the head on".

LOL, actually I can't find the little man rolling around on the floor like me. That's just so funny.