Cleaning and reusing spark plugs

[Mailman]

I think I remember @gggGary saying something the other day about never buying spark plugs. He just cleans up old ones. It got me thinking about this.

Can a cleaned up , used spark plug be just as good as a new one?

I seemed to recall Gary saying that he heated them up with a torch and brushed them off. And sure enough I went on YouTube and there are a ton of videos showing how to clean and reuse spark plugs, several of them include heating them up with a torch and brushing them off. Some other methods,
Soaking them in gasoline and brushing
Brushing and sandpaper
And my method, brush with a small wire brush, spray with electronic cleaner, and fine sandpaper the electrodes.

I do buy and use new spark plugs, but for some reason I never throw the old ones away. I clean them and save them “ just in case I need them”.

So are new plugs really better than a cleaned up set? What do you do?

 

[gggGary]

both
cuz when a motor ain't working right a new plug is such a cheap, easy thing to try. (and eliminate one thing on the list)
I buy new plugs but it took me several years to use up all the new but oil fouled plugs I got in a box with a POS TX750. Torch em dry, brush and install.
I've pulled AT LEAST dozens of "wrong" plugs out of XS650's I've bought. There might be a lesson there.........

 

[gggGary]

PS I use a torch cuz the ceramic absorbs oil, IMHO only a good torching will get it all out of the ceramic.
spray the plug with carb cleaner then torch for a spectacular event....

 

[grizld1]

If you're tuning from scratch you can go through a lot of new plugs before the motor gets happy. Like the G-man says--torch 'em clean and run 'em.

 

[RustiePyles]

I've always wanted one of these.
https://www.ebay.com/itm/1330259413...Wpwto2ouotfoQVWiTdcHJc96cLucLUNUaApV8EALw_wcB

I have one of these, I clean the plugs in my Toro Wheel Horse 520H about once every 5 weeks during mowing season.
https://www.harborfreight.com/pneum...2aZhJyK224iVHKD7VR0XC7wqWXnMVTj0aAhamEALw_wcB

 

[5twins]

I clean my plugs from time to time if they need it. Sometimes multiple cold starts using the choke without long enough run times afterward will blacken them up pretty good. But, I also routinely change them out. I've found the 650, and probably just bikes in general, are pretty tough on plugs. They wear out and while they still function, they don't work quite as well. This is a gradual process and difficult to see if looking at just the plug in question. You need to have a brand new plug on hand to compare to side by side. What happens is the center electrode gradually wears shorter. Compare a used one to a new one and you can often see it.

So, being that the standard NGK BP7ES plugs I use are so cheap and readily available from the auto parts store, I always keep some new spares on the shelf. This is for replacement when the time comes but also for use as a comparison "tool" to judge the wear on the plugs I'm running. I usually end up changing them out about every 2K miles. By then there's usually some wear you can see on them.

So Mailman, grab a new plug and your box of old used ones and start doing some comparisons. If the old ones have 2K+ miles on them, I think you'll find some with worn shorter center electrodes.

 

[gggGary]

Wow 5t wanna ship me a carton of used plugs with 2K on them? I'll never have to buy a plug again.

 

[jetmechmarty]

So, being that the standard NGK BP7ES plugs I use are so cheap and readily available from the auto parts store,

You had best stock up. NGK no longer produces BP7ES and BP6ES. They're only making the resistor version.

 

[Liftedzuki]

You had best stock up. NGK no longer produces BP7ES and BP6ES. They're only making the resistor version.

Just run non resistor plug caps and you're good to go I believe?

 

[5twins]

Well that sucks, lol.

 

[jetmechmarty]

Just run non resistor plug caps and you're good to go I believe?

That's correct. I just don't want to change my caps.

 

[Liftedzuki]

Either resistor caps or resistor plugs. I believe I have ngk resistor caps and ngk non resistor plugs now. Might have to switch around now

 

[Jan_P]

Either resistor caps or resistor plugs. I believe I have ngk resistor caps and ngk non resistor plugs now. Might have to switch around now

So will this work with Boyer Bransden ignition I remember there was specifications for cap resistance

 

[5twins]

Looks like I may have to revise my 2K replacement interval, lol.

 

[Liftedzuki]

The ngk brp7es is 5k ohms.

Edit : quick Google search the boyer has 5k caps (as did my hhb / pamco kit). I didn't see it on Boyers website but you could contact them and check. I don't recall if the cap has any markings.

 

[Jan_P]

Looks like I may have to revise my 2K replacement interval, lol.

Yes Sir
I have a box with to soon replaced Spark plugs
That is sitting on the shelf that will meet a Torch and Wire Brush.
If you hold on to things long enough in this hobby some one will need them.

I bought a Motorcycle jacket black goatskin with padding on the Shoulders
About ..1986 .. 5 -- 8 years later it was out of fashion
then 5 - 8 years later again it was in fashion again.
And so on.
Good jacket now finally it is getting soft ..
It is a weight watching factor. If the pot belly gets to large .. There is a need to loose weight,
Instead of buying new leathers.

 

[hovel]

First off, I ride a '74 model and refuse to believe that this stock ignition system can perform well with any resistance at all.
As for cleaning and re-using plugs, I do this routinely. I clean plugs with a small tool I make out of piece of coat hanger. I grind the last inch as thin as I can like in to a knife shape. I insert the tool into the recess around the porcelain and scrape out the bottom of this area until I feel no more deposits. Then I blow out the plug with contact cleaner and compressed air. Then I open the gap until I can insert a point file to file the underside of the negative electrode and the top of the center electrode so they are clean, flat and kinda parallel. At this time , if you are so inclined, you can file back the negative electrode to expose a small portion of the center electrode when the gap is correct. More exposed spark, old hot rod trick. Obsolete Champion racing plugs with a "J" as the suffix of the plug number were cut this way. Hey, this is almost as anal as indexing plugs with different thickness washers.

 

[xjwmx]

then 5 - 8 years later again it was in fashion again.

It seems to me there is no such thing as fashion anymore, or at least not at the moment. Anything is in fashion. Except the one thing that will never be in fashion again is Magnum P.I. short shorts for men.

 

[jetmechmarty]

It seems to me there is no such thing as fashion anymore,

I beg to differ. Fashion for men here in Mississippi is a camouflaged ball cap. It is considered suitable for fine dining, especially if paired with bib overalls.

 

[xjwmx]

Quite true of course, but note one may also appear sans chapeau without being perceived as a cad.