1995 Mercruiser 4.3 LX OEM Spark Plugs

[EMC 1810SS]

I am trying to figure out what the OEM plugs for my 4.3 LX are. I am pretty sure they are NKGs but short of pulling the cover and climbing in the boat, I cant seem to find anything that says what it came with. Thanks Ahead of time!

 

[Don S]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

AC - MR43T is what came in the engine. NGK BR6FS will work just as well.

 

[Bondo]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

AC - MR43LTS is what came in the engine. NGK BPR6EFS will work just as well.

Ayuh,... Not doubtin' yer word Don, but I think the 95 would be pre-vortec heads, which would be the shorter AC Delco, MR43T...

I think,...

 

[Don S]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

Ayuh,... Not doubtin' yer word Don, but I think the 95 would be pre-vortec heads, which would be the shorter AC Delco, MR43T...

I think,...

Good catch, and you had every right to doubt it, I was 1 page off in the manual when I looked. I was under the Gen + listing.

 

[Jlee815]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

So is the NGK BR6FS still a good plug for his engine or would it be the BPR6EFS? Secondly are you saying that the AC MR43T is the short plug? and MR43TS is the long one?

Not sure if you want my novice cadet opinion here, but I have the same engine 1990 version and I run NGK BR6FS with no problem but it is not the OEM plug.

 

[Bondo]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

Secondly are you saying that the AC MR43T is the short plug? and MR43TS is the long one?

Ayuh,... That is correct,... 'n the MR43LTS is even longer...
Both the MR43T, 'n the MR43TS are used in the Pre-vortec headed motors, 'n the MR43LTS is for the Vortec heads...

I use AC Delcos, 'n can't comment on the NGKs

 

[Jlee815]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

Thanks for the info and education... When I brought my boat the previous owner (not a mechanic) used NGKs... When I got a marine tune up the mechanic put in the AC delcos. I have been running NGKs for 4 years as a recreational boater and had no issues. ... Since Bondo and my marine mechanic used the AC Delcos and the manual says to use AC delcos on this engine I feel a bit upset about just changing my plugs and using NGKs... I will at least keep em in until next year and I think I will go back to the AC delcos. Sorry if I interfered with this post it was not my intention.

 

[Don S]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

The manual also lists the NGK and, sorry to say they list the Champion also.
Look at the plastic cover on your engine, it has a decal with the plug numbers on it.

 

[EMC 1810SS]

Re: 1995 Mercruiser 4.3 LX OEM Spark Plugs

I am not positive, but I think my engine came with NKGs from the factory. I know it has NKGs now. It seems to run fine on them. Thanks for the part numbers. It is NOT the vortec head. I will pick up whichever is either cheaper, or in stock.

Look at the plastic cover on your engine, it has a decal with the plug numbers on it.

I know but I just didnt feel like climbing under the cover today!