Spark Plugs-advice please

[DAKA]

My Tohatsu 9.8 hp two stroke outboard was playing up and running rough at slow speeds , I bought a couple of spark plugs that looked about the right size and put one in the pot that was showing a wet plug.

The results were immediate and I am back to full speed.

The old plug was BP R 7HS-10
The new plugs are BP 7HS-10

The R stands for resistor , my original plugs had a resistor in and the new one doesn't include a resistor.

What is a resistor .
Before I cause any damage do I need to buy two new plugs with a resistor in ?

 

[PaulGooch]

Have a read here DAKA :

http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqresistor.asp

 

[DAKA]

Thanks Paul, they are the same plugs (NGK)then thats good news as the tender does not have plotter/radar etc.
Out of interest I will try the hand held GPS .

Cheers
Pete

 

[PaulGooch]

Thanks Paul, they are the same plugs (NGK)then thats good news as the tender does not have plotter/radar etc.
Out of interest I will try the hand held GPS .

Cheers
Pete

You're welcome, doubt it'll affect the hand held.

 

[Kawasaki]

Just in case
NGK Plugs suffixed '10' .
The gap is 25 thou.

 

[DAKA]

Thanks Kawaski,

The gap I need is 1mm, which is bigger than my feeler gauges*, I used a ruler to measure and guessed these come pre gapped to 1mm , just checked and that isnt 25 1oooths its .6 I think

 

[PaulGooch]

Thanks Kawaski,

The gap I need is 1mm, which is bigger than my feeler gauges*, I used a ruler to measure and guessed these come pre gapped to 1mm , just checked and that isnt 25 1oooths its .6 I think

Nr as dammit, 1mm = 40 thou

 

[Kawasaki]

Sorry, yep 40 thou!
Can't think in metric
Blimey I,ve only just got used to decimal coinage peeps!
Anyway just so's yer know (and others)they have a bigger gap than 'standard'!

 

[VicS]

The hyphen number tagged onto the end of some NGK plugs indicates that they are supplied ready gapped to that number in tenths of a mm. so 10 as said means it is supplied ready set at 1 mm. If that is not the required gap then it has to be adjusted!

There are other preset gaps from 8 = 0.8mm to 15 = 1.5 mm. 10 is the only one I have come across though.

No number means a standard gap ... dunno what that is though!