[Pong]

I have recently bought a 2002 (barely used) Yamaha 25hp 2 stroke outboard. I want to change the spark plugs but on the engine it recommends B7 HS-10. The only thing available where I live is B8 HS --is it ok to use it or should I order in the B7? I am worried about causing any damage by using the wrong spark plug. Also, must add, this is for a boat used only on the ocean.


Any recommendations would be greatly appreciated. Thanks

[BruceAML]

First of all you need to list the exact model number from the data plate on your motor. If you have a model 25MSH3A then the correct spark plugs are NGK B7HS-10. No it is not good to substitute a different heat range. Do you want to jeopardize an engine for the price of 3 spark plugs? Do you have a Yamaha dealer in your area? They can order the spark plugs. You can also order the spark plugs on line. Be aware that in Thailand there are many counterfeit parts but I am sure you know that. Make sure the plugs are gapped and torqued properly. If you do not have the owner's manual, you need to order one. Here is the Yamaha Thailand website.
http://www.yamaha-motor.co.th/Company/water.asp

[isla]

Originally Posted by Pong

I have recently bought a 2002 (barely used) Yamaha 25hp 2 stroke outboard. I want to change the spark plugs but on the engine it recommends B7 HS-10. The only thing available where I live is B8 HS --is it ok to use it or should I order in the B7? I am worried about causing any damage by using the wrong spark plug. Also, must add, this is for a boat used only on the ocean.


Any recommendations would be greatly appreciated. Thanks

The advice is to use the right spark plugs
Can uare quietly the spark plugs B8HS, since most cold does not create problems of overheating it will piston spark plugs.

Never use spark plugs with a degree heat the lowest of the instructions given in the book