Lifetime of pagoda plugs

[gwuisman]

My car had its annual service after 7000 km’s. The mechanic suggested to change the plugs. I doubted as modern plugs in today’s cars are changed after 20.000 or even 25.000 km’s. The argument of the mechanic was that our engines have a hotter burning and a higher CO % which results in a heavier wear. What are your views on this or experiences with the lifetime of your plugs?

Gerard Wuisman
1970 280 sl  

[J. Huber]

In my experience, 7000KM is not an unreasonble amount between plugs. That would be about a 2 year span on average for me (but lots of daily starts and short drives) -- and I usually have the points & plugs changed every two years... as part of the general tune-up.

James
63 230SL

[Cees Klumper]

Hi Gerard - I change plugs about every 15,000 km, and they still look and perform good at that point. Mind you, the cost is low, so it is probably not a bad idea to change them once a year.

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[George Davis]

I would agree with Cees.  In the old days the usual recommendation was to change plugs and points every 12,000 miles (19,000-20,000 km).  For standard plugs, that would probably be ok.

Modern plugs with dual platium/irridium/etc. tips last much longer than standard plugs, so if you are using them they can probably go 30,000 miles or more.

George Davis
'69 280 SL Euro manual

[rwmastel]

quote:Originally posted by gwuisman

My car had its annual service after 7000 km’s. The mechanic suggested to change the plugs. I doubted as modern plugs in today’s cars are changed after 20.000 or even 25.000 km’s. The argument of the mechanic was that our engines have a hotter burning and a higher CO % which results in a heavier wear. What are your views on this or experiences with the lifetime of your plugs?

The life of the spark plug is not dependant only on the technology of the plug, but the technology of the engine it's in.  How constant is the air/fuel mixture?  How clean is the throttle body?  How quickly does the engine warm up?  How much oil gets into the combustion chambers (worn valve train or rings/bearings)?  How consistant is the voltage to the plug?

I would assume these things and more contribute to the life of the spark plug.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420