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

K&B 61 tuning

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

K&B 61 tuning

Old 04-07-2006, 03:21 PM
  #1  
matt407
Member
Thread Starter
 
Join Date: Feb 2006
Location: liverpool, UNITED KINGDOM
Posts: 48
Likes: 0
Received 0 Likes on 0 Posts
Default K&B 61 tuning

HI everyone,

my boat has arrived

At first i thourght there was something wrong with the engine because it was tight at the top stroke and i mean tight. I had to put some real forse when the glow plug was in. The starter wouldnt turn it over with the glow plug in all the way so i have to unscrew it about half way and away it goes then just tighten the plug up..
the piston liner is tapered as there isnt a ring around the piston

I hope this sound familer to you guys. but the guy i had helping me was used to airoplane engines which are smooth all the time apparentaly.

ANYWAY. it started and now i need to know how to tune it. everytime it starts it revs it arss off in the lowest setting. i cant figure out which way to lean the engine and which way to make it rich. because i dont want to damage the engine buy lettting it over rev. i set it up in the bath with the hose pipe conected to the cooling but all i managed to do was soak every where including myself[&:] lol.

as it new to me i havent even been ablt to determine how my throttle it need to idel on the control so i am a bit wherey about chucking it in the sea.

any tips would be great is anti clockwise rich or len or what??

i know this sounds amiture like but with out anyone to turn to and a beast like this engine i am a "out of my depth"

cheers matt
Old 04-07-2006, 03:37 PM
  #2  
matt407
Member
Thread Starter
 
Join Date: Feb 2006
Location: liverpool, UNITED KINGDOM
Posts: 48
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

I have searched for this engine and cant find any info. Checked on the engine all it says is K&B could the perivios owner got it wrong / ment to say .K&B .67?? heres a pic what you guys think. i compared it to the .67 the only difference i can see is the carb on mine the needle is on the side not the top.

cheers matt

Attached Thumbnails Click image for larger version

Name:	Yw67572.jpg
Views:	16
Size:	24.8 KB
ID:	440557  
Old 04-07-2006, 04:24 PM
  #3  
piper_chuck
My Feedback: (12)
 
piper_chuck's Avatar
 
Join Date: Jun 2004
Location: Columbia, SC
Posts: 8,044
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

First, about the tightness. Many of the K&B engines are of an ABC construction. These are designed to with a taper and they are very tight at the top. This is normal. When they are running they expand and loosen up a bit. As a rule, since they are so tight it's best to NOT try to turn ABC an engine over unless you're going to start it.

Next, it's a bad idea to try to run a boat engine at home, and an even worse idea, as you found out, to try to run one inside. Wait until you are at the pond before you try running it again. Oh, and it's a must that you have some kind of retreive boat to go get it when (not if) it dies.

On to the mixture. Richer is usually counter clockwise. Another way to look at it is when you screw the needle in, it makes it leaner, out makes it richer. Standard threads go in when turned clockwise. Screw the needle all the way in, but don't crank it down really tight. Then open it up 3.5 turns, this is a fairly typical starting point, and should be rich.

When you do finally get the boat to the lake and start the engine, it should seem really rich on idle. This is as it should be. If it idles smooth, IT WILL DIE from being lean as soon as you throw it in the water. Also, NEVER rev it really high while it's out of water. If you do this there's a really good chance you will destroy the rod.

And finally, go here: http://www.mecoa.com/kb/parts.htm and take a look around. You should be able to find the manual, or at least one for a similar model.

Cheers!

Old 04-08-2006, 05:32 AM
  #4  
matt407
Member
Thread Starter
 
Join Date: Feb 2006
Location: liverpool, UNITED KINGDOM
Posts: 48
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

thanks piper i will give it a go.
Old 04-08-2006, 10:35 AM
  #5  
matt407
Member
Thread Starter
 
Join Date: Feb 2006
Location: liverpool, UNITED KINGDOM
Posts: 48
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

ok i am gettin ready to start the engine again how much throttle do you guys reckon i would need just to idel. because i have to take the glow heater off, tighten the glow plug and attach the hatch with out it over reving/heating.

cheers matt
Old 04-08-2006, 11:50 AM
  #6  
TERBObob
Senior Member
My Feedback: (21)
 
TERBObob's Avatar
 
Join Date: Jan 2003
Location: Oelwein, IA
Posts: 3,176
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

ok i am gettin ready to start the engine again how much throttle do you guys reckon i would need just to idel. because i have to take the glow heater off, tighten the glow plug and attach the hatch with out it over reving/heating.

cheers matt

Matt ...
not sure exactly how you mean that ... but , only as much throttle as needed for it to stay running whilst at idle . There is no set markings and no set standard ... just as low as possible where it will stay running .
Also ... if you ARE gonna run it on a stand ( meaning not in the water ) at least use a milk jug filled with water and a water line coming out of it to run thru the water jacket . ( mind you , this is NOT the slickest trick in the book to do , but will suffice for when you have a problem carby that gives you headaches [] )
Also , remember to TOSS your boat in when getting ready to run ( use ANOTHER person to do this when possible ) ... do NOT simply PUT it the water as it WILL die .
And when you get your boat to shore , if you spit on the engine ,and it "bounces" around ... the engine is TOO hot ...( too lean on the carb ) so richen the needle OTHERWISE your in for premature engine failure for sure .

Also , you said that the engine REVS its butt off when you start it . Three possibilities . ( assuming throttle is almost closed )
1) fuel line not supplying enough fuel - possible pin hole or two small ID
2) you DO not have the fuel cell pressurized from the exhaust ? ( or from perry pump )
3) carby adjustments are WAY off .

Ron O. ( a mod here ) is a PRO when it comes to marine nitros ... and hopefully he will chine in and give you some advice .
he , more than likely can tell you just about anything you need to know , from prop suggestions to carb settings ....
Old 04-08-2006, 01:07 PM
  #7  
piper_chuck
My Feedback: (12)
 
piper_chuck's Avatar
 
Join Date: Jun 2004
Location: Columbia, SC
Posts: 8,044
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B 61 tuning

ORIGINAL: matt407

ok i am gettin ready to start the engine again how much throttle do you guys reckon i would need just to idel. because i have to take the glow heater off, tighten the glow plug and attach the hatch with out it over reving/heating.
No more than is necessary to keep it running. This is where it's really better to have help. Once you get it started, you focus on keeping the engine running, by giving it little blips on the throttle, while your helper tightens the plug, attaches the cowl, etc.

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 - Manage Preferences - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.