K&B 3.5cc

[BoatDoc]

alright...i love my K&B motors, but right now...i'm getting frustrated with one of 'em. it will run strong for the first run of the day. but then after that it get's goofy on me. it will pull strong for about 15 seconds and then loose power. if i stay on the throttle it dies. if i let off, it will go to idle and putt around. if i get back on it, it takes off like a bat out of hell for about 15 seconds and loses power!! my needle setting is still a bit on the rich side. but with it acting like this, i don't want to lean it out. the motor has just less of a gallon of fuel run through it at this point.

[ahab2]

Check for air leaks

[BoatDoc]

i thought about that, but everything looks good! this is a pretty fresh motor. could the temp. have something to do with it? if i let the boat sit for about 25 min. it will run fine afterwards. but even after a hard full throttle run the head is still cool enough to hold my hand on it. maybe i'll just put my old race motor on it for a while. that thing seems to run no matter what!

[ahab2]

If its that cool then its not geting enough heat. Once the engine is up to temp It has alot more power "ive learned" Im gessing the resson it only screams for 15 seconds after idleing is because by the time 15second is up its too cold but when you idle it it gets hoter because there is not that much cooling there fore it drives good after that. pinch the out going line to slow down the water curent so it dosent cool so much My boat is kind of weak too when there is too muuch cooling Hope this helps. try it out. AND DONT TUNE COLD

[BoatDoc]

i never thought about that. i might have to try it out. i figured it was the alabama lake gods messing with me! i'm itching to get my race motor on the water again, so i may still do the swap, but i'll try messing with the cooling first just to see what happens.

[ahab2]

Did it work I'm just curius. I may be worng. another is to check the carb for stuf thats not suposed to be there.

[BoatDoc]

i ran the absolute crap out of that engine today with no problems!! so there's no telling what it was! now i just need to make a set of trim tabs for the boat and i'll be good.

[ahab2]

Was the temp ok

[BoatDoc]

yeah, the temp was alright. and since it ran good and still put out a decent amount of smoke, i leaned it out just a little bit. it's running strong, so i really don't know what was happening. i probably put about a half an hour of run time on the engine at least the other day, without any hiccups.