Tohatsu M15D sparkplug

[Pogo123]

I recently bought a used 2000 Tohatsu 15 HP (M15D) and am now finding controversy over the sparkplug.<br /><br />An owner's manual didn't come with the engine, but the PDF version from the Tohatsu site lists an NGK B7HS-10.<br /><br />The local dealership mechanic now tells me I need to run a "projected tip resistor" plug (BPR7HS-10) to get easiest starting and best running.<br /><br />The NGK and other plug websites agree with the mechanic.<br /><br />I can accept a "projected tip" argument, but I was of the opinion that the "Resistor" was related to an emissions issue and only required in places like California and Canada ... but that's an area in which I am woefully ignorant.<br /><br />How do I determine who's right ... the downloable owner's manual or the ccurrent opinion consensus ... B7HS, BP7HS or BPR7HS???

 

[John_S]

Re: Tohatsu M15D sparkplug

I believe the resister is to prevent interferance with electrical transmissions, radio, tv, etc. Nothing to do with fuel emmissions. My original 40C manual said to use the non-resister plugs, but latter manuals on the exact same engine had resister plugs. I have been running resister plugs for years with no noticable change. <br /><br />Extended tip plugs are suppose to fowl less. I couldn't find them locally last year. I will try them, if I can get them.

 

[TOHATSU GURU]

Re: Tohatsu M15D sparkplug

Your local mechanic needs to go to school. The R plug is required for Canada because of electrical interferance regulations. Run the B7HS-10 or the P.