Spark plug heat range on Honda mower

[Jeepster_nut]

Hi, my current NGK is a BPR6ES, I have an NGK BPR5ES which is a hotter plug. Would this be ok to use in a honda harmony 5.5hp mower? It is only 1 number hotter. I am in the northeast with summer temps in the upper 70's to 80's. Thanks

 

[Quest]

For Honda mower engines (air-cooled), it would be absolutely desirable if you stay with BPR6ES.

 

[Quest]

Oh and BTW: if you think you are nuts about Honda air-cooled lawnmower engines, just wait till you see the spark plug I have installed on my powerwasher:

It's a NGK iridium plug of the exact heat range (BPR6EIX)! While I cannot tell you exactly if it betters NGK platnum in terms of fuel economy, I do, however, can tell you that I can fire up this baby in one gentle tug.Now that's performance baby!

 

[Jeepster_nut]

My mower is the same way, one pull starting. Would the hotter plug burn a hole in the piston or anything like that? Thanks for the reply.

 

[Hirev]

Don't do it. The 5 heat range is for older honda mowers. The 6 heat range is for the newer Honda emissions motors that run hotter, because they run them with a leaner air/gasoline mixture. To hot of heat range plug on a air cooled motor is a real possibility in burning a hole thru the piston.

 

[Jeepster_nut]

Yikes!

I will keep it for my other equipment. I dont want to trash my Honda over a $2 spark plug. Thanks

 

[Quest]

Hirev is right on the $$ (thx!)

While I don't think the damage is *that* severe, my experience with Honda engines after so many years is that if it ask for heat range of 6, you'd better stay with that.

Playing with heat range on a Honda doesn't really take you too far (really).