Sand blasting plugs?

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oldhead
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Sand blasting plugs?

Post by oldhead » Sat Sep 30, 2017 11:44 am

Anything wrong with Sand blasting plugs, I change plugs when I go to the track, after when I reinstall my street plugs I blast them....Is that wrong? :D :D :D :D Oldhead
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Post by dwilliams » Sat Sep 30, 2017 12:00 pm

I used to blast lead deposits back in the 20th century, and then lead got replaced with MMT, which left a thick claylike shell around the insulator that you could crack off with a small screwdriver. And then MMT went away, and so did the need for blasting.

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Re: Sand blasting plugs?

Post by engineguyBill » Sat Sep 30, 2017 12:09 pm

Not a good idea to sand (or bead) blast spark plugs. Blasting the plug may remove some of the insulator material, which might result in changing the heat range of the plug. The sand blast operation may also result in rougher surfaces inside the plug, which may result in carbon deposits accumulating more inside the plug.
I worked at a Texaco gas station during high school (a very long time ago) and we had a machine there which was specifically designed to sand blast spark plugs. At the time we thought it was a terrific idea! Am assuming there might be some of these machines surviving somewhere in museums.
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Re: Sand blasting plugs?

Post by DaveMcLain » Sat Sep 30, 2017 1:27 pm

It's no problem to bead blast them if you're careful to get them clean/bead free when you're done.

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Re: Sand blasting plugs?

Post by Keith Morganstein » Sat Sep 30, 2017 1:32 pm

engineguyBill wrote:
Sat Sep 30, 2017 12:09 pm
Not a good idea to sand (or bead) blast spark plugs. Blasting the plug may remove some of the insulator material, which might result in changing the heat range of the plug. The sand blast operation may also result in rougher surfaces inside the plug, which may result in carbon deposits accumulating more inside the plug.
I worked at a Texaco gas station during high school (a very long time ago) and we had a machine there which was specifically designed to sand blast spark plugs. At the time we thought it was a terrific idea! Am assuming there might be some of these machines surviving somewhere in museums.
I too remember the little device mounted on a wall. Connected to shop air, filled with some abrasive, a little dust bag on the bottom. You inserted the plug through a rubber grommet and pressed the air valve button. Viola, a clean looking plug, but good luck getting all the abraisive out of it.

I might clean a lawn mower plug in a pinch, but not on a automotive engine.
Spark plugs are cheap, and nothing runs better than a new one!

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Re: Sand blasting plugs?

Post by mk e » Sat Sep 30, 2017 4:55 pm

When I'm working with a new setup and fouling plugs that have only a few minutes of run time on them I bead blast and reinstall. Once its running right and ready for real tuning I put in a fresh set so I don't have to worry about whether of not the blasting damaged anything....plus the blasting removes the cad (or whatever they use now) plating so the blasted plugs will be prone to corrode with time.
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Re: Sand blasting plugs?

Post by jake197000 » Sat Sep 30, 2017 7:48 pm

its almost impossible to get out all the grit from glass beading.look at the plug under maghification and youll see tiny bits stuck between the insulator and the center electrode and somtimes deep in the plug.maybe soda blasting will work.never tried it.

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Re: Sand blasting plugs?

Post by pdq67 » Sat Sep 30, 2017 8:26 pm

Used the gizmo many times when I was in HS back then.

Great for prolonging an oil-burners plugs.

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Re: Sand blasting plugs?

Post by pamotorman » Sat Sep 30, 2017 10:01 pm

back in the 70s rupp snowmobiles used surface gap plugs and I used to bead blast them all the time to clean them

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Re: Sand blasting plugs?

Post by 2.2=8 » Sat Sep 30, 2017 10:10 pm

mk e wrote:
Sat Sep 30, 2017 4:55 pm
When I'm working with a new setup and fouling plugs that have only a few minutes of run time on them I bead blast and reinstall. Once its running right and ready for real tuning I put in a fresh set so I don't have to worry about whether of not the blasting damaged anything....plus the blasting removes the cad (or whatever they use now) plating so the blasted plugs will be prone to corrode with time.
In pinch I bead blasted the plugs for my aluminum headed drag car, raced the weekend, and left them in over the winter. Car was stored in a heated garage, went to replace them in the spring and four cylinders pulled the spark plug threads clean out of the head, they were corroded in because the cad plating was blasted off. I chalked that one up to tuition.

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Re: Sand blasting plugs?

Post by Circlotron » Sat Sep 30, 2017 10:12 pm

Sand blasting will round off the sharp edges of the electrodes like a worn plug and will need more voltage to fire them. If you do blast them make sure you file the electrodes afterwards.

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Re: Sand blasting plugs?

Post by Cougar5.0 » Sat Sep 30, 2017 10:21 pm

I too remember the little plug in grit-blaster - they were "cool" in the '70's.

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Re: Sand blasting plugs?

Post by DaveMcLain » Sat Sep 30, 2017 11:40 pm

I think that the brand of that plug cleaner was Vixen. There was a little lever, one way to blast, one way to blow clean.

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Re: Sand blasting plugs?

Post by MadBill » Sat Sep 30, 2017 11:57 pm

Cougar5.0 wrote:
Sat Sep 30, 2017 10:21 pm
I too remember the little plug in grit-blaster - they were "cool" in the '70's.
This reminds me that I have one that's been tucked away for 25 years in a disused cupboard; I'll have to dig it out and check the brand...
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Re: Sand blasting plugs?

Post by Schurkey » Sun Oct 01, 2017 12:08 am

Takes about one second to clean a plug in my big bead-blasting cabinet.

Yes, I've heard that blasting them can change the heat range. I think it would be more likely with sand than with glass bead, and you'd need to blast 'em awhile to make a difference.

I always anti-seize plugs. Haven't noticed a change in color from the plating coming off, but then I didn't look for it, either.

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