spark plug for OMC 190

[Rick Green]

I just put a set of plugs in my 75 OMC 190. The Clymer manual called for AC-Delco MR43T plugs, so that's what I used. After the plugs were in, I glanced at the remains of the original owners manual, and it calls for a different plug. <br /><br />I contacted AC-Delco, but they have no recommendation for this application. Does anyone know if I'm OK, or should I pull out the MR43T's and go with something else? Thanks!

 

[Boomyal]

Re: spark plug for OMC 190

Good question Rick. I checked my Seloc manual and it gives the same recommendation as your Clymer manual. I have had my '75 OMC 190 hp since new. I am probably only on my 3rd set of plugs but I don't remember what the originals were. I currently use Autolite #24 copper core plugs which you might cross reference check with the AC-Delco plug. <br /><br />There probably is not a wide range of choices for the 302 as it is a low compression engine that wouldn't be so critical for plug heat ranges. Your MR43Ts are probably OK.

 

[Bob in Calif.]

Re: spark plug for OMC 190

AC plug MR43T is available in Champion's. The old Champion # is RV8C, which was given the new # of 121. <br /><br />But...Champion shows RV12YC (new number of 406), for the Ford 302 marine application for years,'75 thru '89. The gap setting is .035. This is a coppper core plug. <br /><br />OMC calls for the Champion RV15YC4 plug, (new #18) for years '73 thru '85, with the 14mm tapered seat, also set at .035. (copper core)<br /><br />Good luck.......... <br /><br /> ...Bob in Calif...

 

[dvarnadore]

Re: spark plug for OMC 190

AC MR43T's are good plugs I have used them in all my marine engine's with great success. stick with a winner<br />Good Luck