Spark plugs for 2006 Tohatsu 18HP...

[chrispy1]

I recently bought a Tohatsu 18 2-stroke and the manual specifies either NGK B7HS-10 or BR7HS-10 spark plugs. My understanding is that the 'R' stands for resistance but what I would like to know is what difference does it make to the running of the motor using one type of plug in place of the other? are these two types of plugs directly interchangable without any change to the type of leads used? The motor came with the BR7HS-10 plugs installed and runs well, but I am a bit curious as to why they give you choice in the type of plug you can use??

 

[cobra 3.0]

Re: Spark plugs for 2006 Tohatsu 18HP...

One probably costs less than the other...or if your dealer is out of one, he can offer you an alternative? That's my guess anyway.

 

[Paul Moir]

Re: Spark plugs for 2006 Tohatsu 18HP...

If you're running any sort of electronics gear at all you need to stick with the resistor plug. I've never seen an outboard where the R or Q plugs had any impact on performance.<br />The electronic noise the engine will put out without the R plugs is incredible. It makes the VHF useless, messes up depth finders, and sometimes causes gauges to do funny things.

 

[TOHATSU GURU]

Re: Spark plugs for 2006 Tohatsu 18HP...

Canada requires the resistance plugs. The U.S. does not. There is no difference in the operational performance of the engine.

 

[Paul Moir]

Re: Spark plugs for 2006 Tohatsu 18HP...

Huh, really? I never knew that. Thanks!

 

[chrispy1]

Re: Spark plugs for 2006 Tohatsu 18HP...

That explains the sticker on the side of the motor saying that the ignition system complies with Canadian electrical non-interference requirements. Thanks for the response