Author Topic: Cleaning Spark plugs  (Read 1516 times)

wwheeler

  • Vendor
  • Platinum
  • ******
  • USA, TX, Dallas
  • Posts: 2866
Cleaning Spark plugs
« on: June 08, 2020, 14:20:44 »
In light on the new info about NGK dropping their line of resistor plugs, I was curious how to revive fouled spark plugs. I have some that were fouled but are relatively new plugs. At the time, plugs were cheap and easier to drop in clean ones. Many years ago I would have foolishly glass beaded the plugs but have since determined that you never get rid of all of the media up inside the plug. Then that media can drop into the cylinders. So what is the best way?
 
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

col320ce

  • Full Member
  • Gold
  • *****
  • Australia, Victoria, Glen Iris
  • Posts: 588
Re: Cleaning Spark plugs
« Reply #1 on: June 09, 2020, 12:20:58 »
I vote for hitting them with a blow torch until they are super hot to burn everything off.  I dropped new ones in on the weekend as there was a missfire ... just a dirty plug. My propane gas torch was empty so I used new plugs but the set I took out are basically new so I will revive them.
Col

1964 230SL
1965 250SE coupe
1993 320CE Sportline

mdsalemi

  • Pagoda SL Board
  • Platinum
  • ******
  • USA, NC, Davidson
  • Posts: 6694
Re: Cleaning Spark plugs
« Reply #2 on: June 09, 2020, 14:07:39 »
There are a number of cleaners specific to cleaning spark plugs; they are self contained blasters. There is also some blast media specific to cleaning plugs. A fine wire brush and some carb/brake cleaner works wonders, and a high pressure blast of such fluid followed by high pressure air blast should remove all traces of media.

If you think you cannot remove the media in these methods, then try the finest walnut shell media you can find, OR soda blast media. The latter will dissolve in water, the former will not be an issue if traces remain.
Michael Salemi
Davidson, North Carolina (Charlotte Area) USA
1969 280SL (USA-Spec)
Signal Red 568G w/Black Leather (Restored)
2023 Ford Maverick Lariat Hybrid "Area 51"
2022 Ford Escape Hybrid
2023 Ford Escape Hybrid

wwheeler

  • Vendor
  • Platinum
  • ******
  • USA, TX, Dallas
  • Posts: 2866
Re: Cleaning Spark plugs
« Reply #3 on: June 09, 2020, 14:11:39 »
Ok and thanks. I had forgotten about the walnut shells and I have that available. The other methods should work as well.
Wallace
Texas
'68 280SE W111 coupe
'60 220SE W128 coupe
'70 Plymouth Roadrunner 440+6

hansr433

  • Associate Member
  • Senior
  • ***
  • Italy, Tuscany, Torrita di Siena
  • Posts: 219
Re: Cleaning Spark plugs
« Reply #4 on: July 01, 2020, 15:23:11 »
I vote for hitting them with a blow torch until they are super hot to burn everything off.  I dropped new ones in on the weekend as there was a missfire ... just a dirty plug. My propane gas torch was empty so I used new plugs but the set I took out are basically new so I will revive them.

Last year we hosted the BMW Grand Tour, escorted by BMW Classic Factory techs, and this is what they did to revive a 503 engine that was having issues.
Hans
1963 220SE Cabrio (Exterior: Navy MB 332, Top: Haarz Navy, Interior: 482P Sahara Beige)
1963 BMW R69S