plug R43T same as MR43T?

[int76]

I'm in the process of changing the spark plugs on my 3.0 Mercruiser and all the parts store carries is a AC Delco R34T and not the recommended MR43T, are these plugs the same? I've already tried the Autolite 145s and they made it run terrible. Any other suggestions for plugs? Thanks-Josh

 

[bruceb58]

Re: plug R43T same as MR43T?

MR43T are the same except that the metal is more corrosion resistant.

 

[Bondo]

Re: plug R43T same as MR43T?

Ayuh,... The R43T is a Steel bodied plug that Rusts, Badly...
The MR43T is an Alloyed bodied plug that doesn't Rust itself in...

 

[Gary H NC]

Re: plug R43T same as MR43T?

Try Napa if you need them fast or Rockauto.com for the best price...

 

[PitchFork]

Re: plug R43T same as MR43T?

I just purchased 8 of them from NAPA at $2.07 a piece. As a side note stay with AC Delco MR43T. If you go to AutoZone they will try to give you some other brand like spit fire plugs that cost twice as much and they are not the recommended ones in your manual. Make sure to gap them correctly as mine came at 0.040" and needed to be 0.035".

 

[mkast]

Re: plug R43T same as MR43T?

are these plugs the same?

If they were the same, wouldn't they have the same part number?

 

[fat fanny]

Re: plug R43T same as MR43T?

I had the same issue last year and could not find the mr43t's anywhere Napa claims A/C discontinued them? But ona second note I used to be able to get all my marine parts from my local Napa and as of last summer they claimed to have discontinued the access of marine grade parts? and don't even have the parts catalog anymore whats with that?

 

[havasuboatman]

Re: plug R43T same as MR43T?

M: marine
R: resistor
4: 14 mm thread
3: heat range
T: tapered seat.

 

[zbnutcase]

Re: plug R43T same as MR43T?

Autolites will rust like a banshee also!!! 'nutcase

 

[mkast]

Re: plug R43T same as MR43T?

Autolites will rust like a banshee also!!! 'nutcase

Not the marine Autolites.

 

[zbnutcase]

Re: plug R43T same as MR43T?

Not the marine Autolites.

True....but rarely see 'em