Go Back  RCU Forums > RC Boats > Speed - RC Nitro Boats
Reload this Page >

K&B 3.5cc HELP

Notices
Speed - RC Nitro Boats For all your rc nitro fuel burning boating needs.

K&B 3.5cc HELP

Old 11-26-2007, 08:11 PM
  #1  
gabcriverrat
Junior Member
Thread Starter
 
Join Date: Nov 2007
Location: , CA
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default K&B 3.5cc HELP

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.
Old 11-26-2007, 08:15 PM
  #2  
dicko
Senior Member
 
dicko's Avatar
 
Join Date: Feb 2004
Location: Adelaide, AUSTRALIA
Posts: 3,507
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 3.5cc HELP

i run the OS max, i run that on 25% nitro & 16% oil. not sure what the K&B needs though.
Old 11-26-2007, 08:17 PM
  #3  
gabcriverrat
Junior Member
Thread Starter
 
Join Date: Nov 2007
Location: , CA
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 3.5cc HELP

ok thanks
Old 11-26-2007, 08:18 PM
  #4  
piper_chuck
My Feedback: (12)
 
piper_chuck's Avatar
 
Join Date: Jun 2004
Location: Columbia, SC
Posts: 8,039
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 3.5cc HELP

Wait a bit, the thread will be moved to the nitro forum.
Old 11-26-2007, 09:19 PM
  #5  
Dan S
Senior Member
 
Dan S's Avatar
 
Join Date: Aug 2006
Location: Oromocto, NB, CANADA
Posts: 2,882
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 3.5cc HELP

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.
Old 11-26-2007, 11:37 PM
  #6  
jetpack
My Feedback: (1)
 
jetpack's Avatar
 
Join Date: Oct 2002
Location: Hobart, IN
Posts: 2,477
Likes: 0
Received 1 Like on 1 Post
Default RE: K&B 3.5cc HELP

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....
Old 11-29-2007, 09:33 AM
  #7  
Ron Olson
My Feedback: (1)
 
Ron Olson's Avatar
 
Join Date: May 2002
Location: Kalamazoo, MI
Posts: 18,688
Likes: 0
Received 20 Likes on 17 Posts
Default RE: K&B 3.5cc HELP

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.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.