K&B break in.

[29tunnel]

K&B break in.

Hi, I 'm looking for a good way to break in a new K&B 3.5 outboard. My thought was to use a lower nitro content, say 20% with a very rich setting for 2 tanks and then start using 40% rich at first and then start to lean it out. What is the optimum running temp. of these engines. This engine is 12 years old ( #8906) and never been run! Also I,m trying to find some spare flex-shafts. Thanks ---Don

 

[Propjockey]

Re:K&B break in.

Don, true enough on the rich part. The richer, the better. But I break mine in using the same fuel I plan on running after break-in. If i plan on running it on 40%, that's what I break it in with.

Optimum running temp? Spit test. (I'll elaborate if you want)

"NEW" hyperformance flex shaft's in stock for 3.5,7.5/13 ccoutboards.

3.5......$5.95 each

7.5......$6.95 each

Give em a try.....

Tim

Precision Boats Racing.com

[email protected]

 

[billr]

Re:K&B break in.

My vote for breaking in a new K&B is.... A Sledge hammer!!! Just kidding!!!

From what I have seen, heard, and listened to, breaking in with a lower nitro % (say 40%) is good. Now on the other hand, you occasionally hear that phrase... breakin it in like you are going to run it. I have broken engines in on 40 % and 70 %- both were REALLY rich for at least 1.5 tanks of fuel, then leaned from there. Both breakins were good, both ran fast, still have good compression...I really cannot tel the difference.

Billy R.

 

[29tunnel]

Re:K&B break in.

Thanks Billy and Prop. -I have also 2 O.S. 3.5's that have been run on a steady diet of 20% blue thunder for more than a year. Do you think moving up to 40 or 50% would cause me any problems. Thanks --Don

 

[Jerry Dunlap]

Re:K&B break in.

29T,

I always run my O.S. 21 OBs on 65% fuel. I toss a couple of ounces of castor in a gallon.

JD

 

[_laxmasta2039]

Re:K&B break in.

yikes,

im expecting a 3.5 OB and that hydro to go with it any day now, and the only fuel i've got is O'donnel 20%.....kinda scares me when you guys say "low nitro" and numbers like 40%!! at least i know i wont have many problems breaking in with too much nitro!!

Joe

 

[Propjockey]

Re:K&B break in.

Don--running higher nitro shouldn't cause problems, you just might not see the same performance as if you had broken it in with the hot stuff. Then again, who knows?

Something else to think about...is it about time for a rebuild on the OS? A new piston and sleeve will have to be broken in, use the high nitro at that time.

Joe--K&Bs will scream happily along with 40-60%+.

 

[billr]

Re:K&B break in.

Running higher nitro does not cause any problems while running. Just make sure you clean your engine afterwards. I use Automatic tranmission fluid for afterrun oil. I opened the engine up the other day, and man you talking about CLEAN!!!! it really does the job!

I'm not talking a drop or two either, I fill the engine full; turn it over by hand a few times at different angles without the plug in. I then putthe starter on to blow it all out, then fill it again and put the plug in and leave it. It REALLY WORKS GREAT!!!! Do this after every days run on high or any nitro and you will be better off.

Billy R.

 

[Kris Flynn]

Re:K&B break in.

But you can still run Outboards on less than 40%...Remember Oscar is only running 25% and it getting pretty good performance out of his K&B...i'm running about 25% and its only stock so far and it seems to go well

Kris

 

[billr]

Re:K&B break in.

Well, if I am getting ready for a race or just running on the weekends then I run 20 - 40%. On race days it is 65% to 70%. There is a big difference in performance in the two areas if it is done right.

Billy R

 

[duc]

Re:K&B break in.

Yep you are right Kris. I would not know what to do with the extra power the higher nitro could deliver on my ABS Dumas. And remember the extra power will wear engine parts faster to.

But off course that is in the US no problem at the moment.

 

[snowdog-2112]

Re:K&B break in.

Kris, Oscar, all,

Just an observation from a mis-placed or is that dis-placed US racer. Fuel is much less expensive in the states and it's readily available. I recall getting a gallon of 45% for about $30 in Tacoma where over here, if you can get it, a liter of 20% will cost about 30 Euro. You do the math, 120 Euro for about a gallon of 20%, I DON'T THINK SO.

I'm going to consult with a couple a buddies over here and inquire about my helping them make fuel. Or see what the Hazmat charge is on shipping a case of JD's 65% will run me. ???

 

[Jerry Dunlap]

Re:K&B break in.

Bryan,

I have a feeling the shipping cost for sending nitro fuel to Beligum would be rather high. It's expensive just to have it shipped here in the states.

JD

 

[duc]

Re:K&B break in.

Hi Bryan!

You did go to the wrong store I guess!! 1 Litre of 20 percent will cost 'only' something about 15 Euro in Holland?

Oscar

 

[not2bright]

Re:K&B break in.

tacoma ? another person from washington? kitsap r/c boat club needs your support come and race!