BVasily
Member
Read a number of posts re spark plugs. Will be installing new set next week. Can anyone give me the proper AC plug to use?
confusion about what spark plug to install on 95 330 DA /w Merc 7.4l V-drive
- Thread starter BVasily
- Start date
BVasily
Member
P.S. 7.4L Bluewater manual calls for part 33-59571 but unable to cross ref this to an AC plug.
my3sons
Well-Known Member
- Feb 24, 2009
- 3,046
- Boat Info
- 2004 400DB, Onan 9 kw Generator, Highfield RIB,
- Engines
- Cummins 6CTA M-3
I used to run MR 43T with a .035 gap
rondds
Well-Known Member
- Oct 3, 2006
- 8,859
- Boat Info
- 2001 380DA
- Engines
- Merc 8.1s (2008)...Hurth ZF 63 V-drives...WB 7.0 BCGD (2013), Garmin 8208 & 740 MFDs, GMR 24xHD dome
I've used AC MR43T, Autolite 25s, Champion RV15YC4 and have never noticed a difference. Stamped right on my cover assembly is the AC part number, which I have now settled on. Yours should be the same. Gap is .035 as stated above. Don't overspend on plugs. Rockauto sells the ACs for $1.78 each.
Captain Allen
Member
- Feb 2, 2009
- 356
- Boat Info
- 370 EC 1994
- Engines
- 454 Mercruisers, straight drives
MR 43T's or MR 44T's. The 44 is a little hotter plug, according to my engine guy. I am running the 44t's now and have had no problems.
