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FrankShore's avatar
FrankShore
Explorer
Aug 13, 2014

Extra Spark Plugs For Generator & Other Questions

My Generator came with a not so hot spark plug and I'd like to replace it and also carry a spare. Which model/brand do you guys suggest?

Smarter Tools Yamaha Generator - Costco - $599.99

The instructions also said that it needed to be broken in for 20 hours. Is just letting it run hooked up to a floor type fan for 20 hours enough?

Also, is standard 10w30 car oil ok to use, or should I use a 4 stroke 10w30?

9 Replies

  • Tvov's avatar
    Tvov
    Explorer II
    FrankShore wrote:
    The owners manual calls for a NGK BPR6HS spark plugs, so I ordered a few extras . I hope they're properly gapped....


    Why not just pickup a basic spark plug gapping tool anywhere that sells car parts? Seems like you are doing (or at least planning on starting to do) a lot of your own engine maintenance, so you will use it a lot.

    Something simple like this will work:

    http://www.napaonline.com/Catalog/CatalogItemDetail.aspx/Spark-Plug-Gap-Gauge/_/R-BK_7769150_0434862340

    Sorry, had trouble for some reason posting a link.
  • MEXICOWANDERER wrote:

    IMHO engines do have a favorite spark plug brand. Visit some Yamaha forums online and see if you can pick up some tips. Nothing like a lot of comments from actual owners. You do need to weed through the duff, but using wisdom and common sense, forums can be informative


    This is an excellent piece of advice, thank you getting up to speed on resources on this kind of thing!
  • nevadanick wrote:
    Pull the plug and see what's in it now. As for oil I use She'll Rotella 5-40 in just about everything I own.

    Thanks NevadaNick, I will do the pull test today and see what spark plug it shipped with! Appreciate your opinion!
  • The owners manual calls for a NGK BPR6HS spark plugs, so I ordered a few extras . I hope they're properly gapped.

    For what it's worth, the Smarter Tools Generator is powered by a Yamaha MZ80, which I continue to read are above and beyond their nearest competition - The HONDA. If you'd like the link, I'll be happy to post it!

    I don't think Costco carries a product nationwide, unless they have a good idea that the particular product is a good, decent, product!
  • Pull the plug and see what's in it now. As for oil I use She'll Rotella 5-40 in just about everything I own.
  • If this critter is variable speed (inverter) changing the load (speed) after an hour is universally recognized as offering the "best break in". Even Transamerica DeLavalle, who make ships engines and Pielstick of Germany recommend varying the engine speed during break in. My dad used to haul me off to various shipyards and vendors where my inevitable 10,000 questions (at age ten) sent people scurrying off.

    IMHO engines do have a favorite spark plug brand. Visit some Yamahahaha forums online and see if you can pick up some tips. Nothing like a lot of comments from actual owners. You do need to weed through the duff, but using wisdom and common sense, forums can be informative.
  • Our owner's manual indicated the viscosity of oil required varies with the ambient temps when generator is predominately operated. We use 15W-40 which corresponds to ambient temps of 10 degrees to 100 degrees. We always run synthetic and currently have over 700 hours on our unit.

    Break in period requires a low wattage device and a fan will do the trick nicely. Generators tend to run better the more often there are utilized, they should be exercised regularly if they don't get much use.

    Some generators come with poor quality spark plugs, getting a better made spark plug is wise and carrying an extra wouldn't hurt. Haven't heard much feedback on the Smarter Tools genny available from Costco, it would be nice to hear some feedback as to your experience with this new entry in the portable generator field. Good luck and enjoy your new generator.
  • The owners manual will tell you exactly what type of oil to use. That's what I would use if it were my generator.

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