1979 Mercruiser 898 best spark plugs?

[RinkerTinker]

Hey iboats!

I tried to do my own research as to the appropriate spark plugs for my 1979 Mercruiser 898 and came up with NGK Nickel Spark Plug (BR6ES). Can anyone confirm this is correct before I go purchase them? Also if any other spark plugs are better for performance and reliability please recommend! Looks like its gonna be tricky changing them so I don't mind spending extra money if its worth it! Thanks


I look forward to updating my progress and adding pictures!!! Does not appear to be many 1979 Rinker Rideau restorations completed out there (at least not as many pictures as other boats). Ive changed the starter, alternator, and many more engine parts! Also, I've made great progress rebuilding the interior, doing minor fiberglass repair, redesigning the electrical system and all my new electronics are in!!!! Thanks again IBOATS!!!!

 

[achris]

Re: 1979 Mercruiser 898 best spark plugs?

The correct plug as per the service manual is

NGK - BR6FS
AC Delco - MR43T

Either plug is good...

Chris.......

 

[Don S]

Re: 1979 Mercruiser 898 best spark plugs?

You really only have 2 choices, the AC MR43T which is the OEM GM plug, or the NGK BR6FS (Not ES as you have in your post).
Don't even consider Champion unless you enjoy engine running problems.

 

[RinkerTinker]

Re: 1979 Mercruiser 898 best spark plugs?

Thank you! I'll be going with the AC Delco - MR43T. Looks like local shop has 8 left! perfect! This would have not been fun if I bought the wrong ones!