K&B 3.5cc HELP
#1
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I have an old 3.5cc Inboard marine engine. P/N 8912 What type of fuel is needed?
I need the fuel % of nitro and any usefull starting tips. How many turns is the needle valve etc. and what % of oil in fuel. I found the old directions but after 20+ years it is poor shape.
I need the fuel % of nitro and any usefull starting tips. How many turns is the needle valve etc. and what % of oil in fuel. I found the old directions but after 20+ years it is poor shape.
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You can run your engine on Nitro boat fuel (Red Max, WildCat others I can't think of right now) anywhere from 10% to 65% with 14 to 18% oil.
it all depends what is your intention, Race or Fun.
I have been running WildCat Promix with 35% Nitro and 18% oil.
Has for settings you can look here for starters:
http://www.mecoa.com/faq/carb/needle_marine.htm
Dan.
it all depends what is your intention, Race or Fun.
I have been running WildCat Promix with 35% Nitro and 18% oil.
Has for settings you can look here for starters:
http://www.mecoa.com/faq/carb/needle_marine.htm
Dan.
#6

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I was going to post an instruction sheet but it doesnt allow it to zoom large enough to read clearly. It is for a 3.5 SS version, and some of the notes wouldn't apply I dont think, but gives general operating instructions. Send me a PM if your interested with your email and I can send it. Just click my name over in the left column there and it will bring you to my profile, and look for the "send eMail" button and I'll return it with a copy....
#7

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I don't know by the number which version this is but by the age I'm guessing that it's a black carb version.
The little K&B's love the nitro and will respond well to any extra. 45% is a good place to start as it's good for sport running or racing and not as finicky on a hot day. Going lower is no problem either but keep the oil percentage at 18-20%.
3-1/2 turns out on the needle is a good place to start then adjust from there. K&B used to advise 4-1/2 turns but I found that it was too rich there.
www.mecoa.com may still have the owners manual for that engine online.
The little K&B's love the nitro and will respond well to any extra. 45% is a good place to start as it's good for sport running or racing and not as finicky on a hot day. Going lower is no problem either but keep the oil percentage at 18-20%.
3-1/2 turns out on the needle is a good place to start then adjust from there. K&B used to advise 4-1/2 turns but I found that it was too rich there.
www.mecoa.com may still have the owners manual for that engine online.