Need help

[david62]

I have one K&B 7.5 O/B engine (8702) break-in and kept for few years. Now I want to put it to use and past experience with this engine tuning problems. I will be using 25% nitro, can somebody help tell me the best needle setting or how to keep this engine from frustrating me. Please help and thanks in advance.

 

[Grimracer]

I have one K&B 7.5 O/B engine (8702) break-in and kept for few years. Now I want to put it to use and past experience with this engine tuning problems. I will be using 25% nitro, can somebody help tell me the best needle setting or how to keep this engine from frustrating me. Please help and thanks in advance.

David?

First I would check or just replace the bearings. Seems like after sitting they need to be changed. Not only that but they are the number one cause of eratic engine runs. Its not hard to change them but if you dont want to tackle it send it to a good engine builder. They can do it in short order time.

The needle setting is a mistery to all.. its dependent on the temp and prop and as you have already stated fuel, lots more but you not need to worry about that at this time.

Turn the needle out far enough to get the boat to just go around.. not fast, just so that it does not quit while on the water. If you get the needle past about 4 turns out and its still quitting change the bearings.

The goal for less frustration is SLOW DOWN.. or at least not as fast as you like.. As you get to know your setup, i.e. prop height, hull ride, driving style, you will be able go faster with the same lack of frustration.

Have fun and keep us posted.

Grimracer

 

[VansRacing]

I have one K&B 7.5 O/B engine (8702) break-in and kept for few years. Now I want to put it to use and past experience with this engine tuning problems. I will be using 25% nitro, can somebody help tell me the best needle setting or how to keep this engine from frustrating me. Please help and thanks in advance.

David,

What State are you in? We may know someone close to you that could help you also.

-Carl,

 

[david62]

I have one K&B 7.5 O/B engine (8702) break-in and kept for few years. Now I want to put it to use and past experience with this engine tuning problems. I will be using 25% nitro, can somebody help tell me the best needle setting or how to keep this engine from frustrating me. Please help and thanks in advance.

David,

What State are you in? We may know someone close to you that could help you also.

-Carl,

Thanks for the advice guys. I am from Malaysia....too bad too far out.

 

[piper_chuck]

Thanks for the advice guys. I am from Malaysia....too bad too far out.

I was going to suggest that you go to the Malaysian Hangar on RCU, but I see you're already there. Nice boats and nice lake! If I get another chance to visit KL I'd like to arrange some boating with you and some flying with Wilson.

 

[david62]

Thanks for the advice guys. I am from Malaysia....too bad too far out.

I was going to suggest that you go to the Malaysian Hangar on RCU, but I see you're already there. Nice boats and nice lake! If I get another chance to visit KL I'd like to arrange some boating with you and some flying with Wilson.

Done what Grimracer advised and boat is running well whole day. Thanks.

PiperChuck, welcome to Malaysia but I am in KK (kota Kinabalu) not KL.

Happy boating.