~~ Ngk - BL6 Spark Plug ~~

Discussion in 'Spare Parts, Tools & Product Developement' started by Karryhunt, Apr 21, 2010.

  1. Karryhunt

    Karryhunt Member

    I don't know if anyone else has had problems sourcing the BL6 plug recommended for the little 48cc engine but I spent hours tying to find it locally.

    Finally found it at Auto Zone but if you ask for it by BL6 they will tell you its not available. Just tell them its for your 1960 AMC Rebel with a 4.1L 2BL 8 cyl. engine. :ack2: Where there's a will there's a way.




  2. zaviii

    zaviii Member

    That good info, how does it perform?
  3. AussieSteve

    AussieSteve Active Member

    Usually, an NGK B5HS or B6HS is recommended for these engines. They're really easy to find.
  4. Pablo

    Pablo Motored Bikes Sponsor

    I THINK a BL6 will fit, but the thread reach is 1.5mm shorter than a BXXHS. I don't see the shorter thread reach as an advantage for heat transfer or mechanical engagement, but for some reason if you have a really "narrow" (short?) plug hole, it may be an OK choice. No need to knock yourself out getting one.

    But BL6 must be some older numbering scheme.

    Also, NGK no "S" at the end must default to an "S". :thinking2:

    Last edited: Apr 23, 2010
  5. Karryhunt

    Karryhunt Member

    I think you are probably right. The only reason I mentioned the BL 6 is because that is what the instruction manual suggested. I would like to try the NGK R7 HS but it ain't to be found anywhere in south Florida. I'll payPal anyone $15 to send me one. Any takers?

    Attached Files:

  6. Karryhunt

    Karryhunt Member

    Not as good as the original one that came with the engine. It seemed to be a little weak in the mid to top end range. Sorry I recommended it now. Can I delete the post?
  7. Pablo

    Pablo Motored Bikes Sponsor

    No biggie man. That's what trial and error is all about. Those must be some old instructions out of China, by the NGK nomenclature.
  8. mountain80

    mountain80 Member

    I run a bl6 on a modified puch head as I have recut the combustion chamber and had to take material out of the top of the cylinder to lower compression somewhat. The b6s is 1/2'' reach and the bl6 is 7/16''. I bought mine at napa and they were cheap at 3$ each i believe.
  9. Lockandload187

    Lockandload187 New Member

    Im in Australia and the NGK R7HS is the best you can get them anywhere $6 you want me to send you a bunch?
  10. butterbean

    butterbean Well-Known Member

    It's a B6L, not a BL6. It's a plug apparently used in Harley Sportsters, as that's what they matched my stock plug to at a motorcycle shop back when I still rode 2 strokes. If the people at Auto Zone told you it wasn't listed, they were either lying, stupid, or typed in bl6 instead of b6l like they should have (did you say BL6 or B6L when you asked? It does make a difference). With NGK's designations, a plug marked 6 is hotter than a plug marked 7, but colder than a plug marked 5. A B6L is not a direct match to the stock plug, because it's hotter but the Chinese don't know that (or whoever made the cross reference list I read doesn't know it?). I ran the B6L in my stock 48cc with 87 octane, blew the rings in it. It seems weaker, but what's actually happening is the hotter spark is igniting the mix faster, causing the engine to lose power because pre-ignited mix doesn't burn at the correct time. The mix burns before it's compressed, and when it does compress there isn't as much left to burn. A B6L would be a great plug for an engine with a high compression head running 90 octane or above, but it's absolutely no good for a stock engine running low octane.
  11. butterbean

    butterbean Well-Known Member

    It also seems weaker due to lowered compression, with the reach being shorter than the stock plug.
  12. HeadSmess

    HeadSmess Well-Known Member

    ignore this drivel as it shows a complete and utter lack of understanding of how the heat range of spark plugs works, going as far as to claim that the heat range of a plug affects ignition timing. ie, read the posters signature very carefully ;)

    btw. i run a plain old lawnmower, available anywhere, CJ8 (champion) or BM6A (NGK) which also has the shorter thread (what the A means) with absolutely no noticeable difference to any other plug that happens to fit, which is ANY NGK plug with B as the first letter, as long as there is NO E in the code... the E being a 3/4" deep thread. way too long. ie, b6Es is a no go. as is bpmr8eix...