Can these plugs be cleaned? - PeachParts Mercedes-Benz Forum

sbourg · #1 01-21-2009, 01:26 AM

Swapped these for a new set in our m'home today, before having it smogged. It passed.

Steve

compress ignite · #2 01-21-2009, 01:39 AM

Any thing can be cleaned...

I believe your question [implied] was ,"Will they be any good after cleaning?"
Answer: The Center Electrodes may be too worn to be any good.

mpolli · #3 01-21-2009, 02:47 AM

I don't think anyone has recommended plug cleaning for about 50 years. Seriously. This was common practice until about 1960 maybe. If they are working good leave them in. Otherwise replace them. PS, I had a Champion plug disintegrate on me and wreck my Supra engine. I take it back to the parts store and the guy says, "yeah, they do that." WTF??? I don't use that brand anymore. But hey go ahead and experiment, clean them if you want. I used to have great results cleaning dist cap electrodes. But they didn't have any platinum plating. I think the previous poster is correct, those look pretty far gone.

Strife · #4 01-21-2009, 02:56 AM

I just don't think it's worth it - and I hope you get to the bottom of the problem that caused this. When there was leaded gas, plugs really did get bad in 10K miles, and in terms of real money, I think plugs in terms of $ per mile were more expensive in the 60's than they are now, so more people cleaned them. One of the big hazards of cleaning was getting ALL of the blasting abrasive out of the plug after cleaning. ALL of it. Sand in the combustion chamber = not good.

E150GT · #5 01-21-2009, 08:08 AM

Those look terrible. I wouldnt waste on minute cleaning them. Plus new are cheap.

Kestas · #6 01-21-2009, 10:02 AM

How do you plan on cleaning them? I clean my plugs by gritblasting and make sure all grit is cleaned out before putting them back in service. I get at least 50K out of a set of plugs that way before the center electrode has eroded too much. Your plugs look too eroded to clean.

pawoSD · #7 01-21-2009, 10:33 AM

It costs less than $20 for a new set of plugs. Toss them!

sbourg · #8 01-21-2009, 12:31 PM

Sorry guys - I was joking in the title! The replacement set cost $16. Hadn't started the m'home since we got back from our 1-mo. fall trip, during which it always started and ran fine, seemed to get our typical 8-9 mpg. Started it yesterday to get it smogged, and it ran rough, so I decided to service first - test later. The mystery is how it ran so well for so long! Anyone who has worked on one of these knows it's no mystery why I waited so long to CHECK the plugs - a real pain for the front ones. As to their condition - it's an old heavy-duty 4bbl Chevy application and burns about 1 qt/1000mi., so I just need to do the deed more often.

Steve

sbourg · #9 01-21-2009, 12:37 PM

Oh, and BTW, it has run way too cool for too long due to an over-zealous rebuilder who punched a hole in the thermostat a decade ago. More recently I found out and put in a new 180 when I replaced the radiator and hoses, though it is still running cooler than ideal. Spec is 195, so I may do the switch soon. Most use is in cool to cold weather, often at altitude where the 4bbl runs rich, etc.

Steve