Spark Plugs

[CreakyDecks]

While rooting the other day I found a few shiny new spark plugs still in boxes. They are B6HS. Upon looking at my outboard the ones fitted are B6HS-R. What's the difference and should (could) I put the new ones in?

 

[Lakesailor]

the R refers to resistance. Not enough detail. It's not a Johnson or Evinrude is it?

 

[VicS]

the R refers to resistance. Not enough detail. It's not a Johnson or Evinrude is it?

I think you are wrong about the R unless the OP has misread the number

R for resistor suppression would be in the first part of the code eg BR6HS


At the end an R means "special ground electrode" ( dunno , dont ask!)

although after the hyphen it is usually a number, if anything, which indicates the preset gap


NGK code here http://www.ngksparkplugs.com/techinfo/spark_plugs/partnumberkey.pdf

Right about not putting resistor plugs in OMC engines though , at least in those with CD ignition


Creaky Decks

what engine do you have, Make, hp and year. Model number and serial number if possible.
Have you misread the number on the plugs. Are they really BR6HS if so you can probably use B6HS but they wont have interference suppression.

 

[Lakesailor]

After some Googling it seems that plugs with a stylised R (a bit italic with serifs at the bottom of the code number) have a ceramic resistor of 5K ohms

It isn't really part of the plug number, more of a trademark on the ceramic insulator. Rather confusing really.