Need some help

[alby]

I been working on a boat project for awile. Everything was bought off eBay and it's been a blast. Anyway I'm all finished and I thought I try starting the K&B 7.5 8702 outboard. It started and revved up so I closed the throttle all the way to kill it and than it idled just fine. I'm alittle confused, on all my cars and trucks the barrel is usually open like 1/16th of an inch and this is all the way closed and running fine? It's the "94" series carb I think, has a remote needle valve and a brass disk on one side. I can't believe I have that much of an air leak somewhere, I dunno let me know what you think. Also when you launch a boat can you do it at idle or do you need to rev it up. Thanks,

Mike

 

[Jerry Dunlap]

Mike,

It sounds like the motor is running too lean. Try opening the needle-valve about 4 to 4 1/2 turns from completely closed. Also, the low speed disc may need to moved to the rich side. You also might want to check to be sure the carb is all the way down against the block.

Most of us launch our tunnel boats at about 1/4 throttle. It's really not a good idea to rev up a motor before launching.

Jerry Dunlap

 

[TimD]

Hey Jerry,

You wouldn't be using a FUTABA radio by any chance would you?? HA HA ;D

Tim.

 

[duc]

Mine 11 cc K&B with the 94 series carb does the same thing do.....

But I'm not sure if the setting of the carb is right (it has the right fit I'm sure) because I only run it for a few minutes. It does have a nice idle run at the moment:

You know, slow and a DENG DENG DENG DENG sound?

I thought that was the sound of a rich running idle engine. I like that because it makes a far more relaxing walk to the water as when it is reving high...

 

[alby]

Thanks Duc thats what I wanted to here. I did start mine again tonight after checking for air leaks and it starts when it's just barely cracked open. I'm going to try my first launch this weekend. I did have a air leak where the carb goes into the block like Jerry said, but this motor is used and I could'nt get it to seal. I used a little RTV sealent and that did the trick. Thanks for the info.

 

[duc]

glad I could help.

Does anyone have a drawing of this type of carbs? Or maybe a place on the web were I can find one?

I have another question for you (or others 94 series owners of course): Does your carb have two or one screws on the the brass disk? I'm asking this because my 11 cc has two and the second hand 7,5 cc has only one. ???

 

[alby]

www.modelengine.com/guidelst.htm

page down and find the outboard engines. There are blow ups of the engines and carbs in PDF format.

 

[duc]

Alby,

I knew this link but these are the wrong carbs. And accept for that it are just drawings of two different carbs. Like a 3,5 cc has the same as a 7,5 ss.......

Hope they put the right ones pretty soon.

Until then maybe somebody else? Maybe someone who can scan the paper that came with the engine? ???