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Old 09-10-2012, 10:48 AM
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Join Date: Sep 2012
Location: , AK
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Default 1994 K&B .21 outboard in 2012 help

In a blast from the past, I decided to take my 6 year old son RC boating.

I have a Prather 31' Deep Vee outboard with a 1994 ish Black carb K&B outboard 3.5. Back then I was into airplanes and had great experience with plane engines. I built my Prather and being in Alaska I didn't have anyone around to help me with the boat. It was a tempermental engine and incredibly unreliable... so I shelved it.

Fast forward to now, last week I gathered up my stuff, charged the batteries and took my son boating on Sunday.

Here is my my problem:

The motor is still tempermental. Ornery to start and keep running. There seems to be a lot of oil coming from the exhaust port and maybe crankcase of the back of the engine where it mounts on to the lower unit/drive. Is this an issue? Would this make the engine a poor runner? Do I need to remove the powerhead and seal those surfaces? I have checked the tank and fuel lines (and exhaust supply pressure line) for air tightness and they pass muster.

The carb seems to need to be run more lean than the reocmmended starting of 3 1/2 turns open. As it is running it is too rich if there is fuel sputtering out from the carb right?

Finally I got it running and let the boat loose and after it dying a few times (and then leaning it out) It ran, but then I broke the flex shaft. I live in Alaska, please direct me to a website where I can order (if at all) a new flex driveshaft for this motor and lubrication.

Also this motor is bone stock. What kind of r/c glow plugs should I order (etc rc long/ short, idle bar or no idle bar). Does anyone have a suggestion on a prop. What about % nitro fuel?

Thanks for the help! PS when the boat died, my yellow lab jumped in the water and was of no help retrieving it, yet when I turned my back she somehow bit into the hull and punctured it! Ha ha ha... guess I need some epoxy and little square of glass as well.