short run spurts

[puppers613]

i have a 3.5 outboard k+b i couldnt get it to run more than a few sec. so i tore it down seen alot of cyl. wear put a new piston/cyl in and im still getting same thing does nitro % a big issue with these im using 20% i seen 25 is the min.any help would be great . :?

[MECOA]

20% is fine. This problem is typical of a lean mixture.
read
http://www.mecoa.com/faq/carb/needle_marine.htm

[piper_chuck]

And to back up the nitro percentage, mine have always been fine even on 10 or 15% nitro.

[nitrorc5]

i have an inbored that had the same problem
check to see if there are bubals in the lines
if there are then thats your problem
what i did to get rid of them i changenged the lines and checked for holes in the tank
there was one and i super glued it and covered it with silicon
know my engine idals runs evenly with no spers of rpm

[malter]

I'm having about the same problem, and need some help as a newbie. I have an 11 CC outboard. Trying to make sure engine works before I spend a lot of $. Therefore, trying to run dry just to see if it works. I can only get about 10 seconds before motor dies. Seems like not getting fuel. When reprimed, starts up again, every time, but only for 10 seconds (tops). Checked fuel delivery system and everything good and pressurized. Tore motor apart and all looks excellent. Any thoughts appreciated. thanx.

[MECOA]

READ THIS

http://www.mecoa.com/faq/carb/mixdisk/mixdisk.htm

AND THIS

http://www.mecoa.com/faq/carb/needle_marine.htm

[nitrorc5]

well maby you both have engines with a littal nipal in the back that looks like it is used to pressur the engine (it doesnt)
it was used in early years to give the engine more power using two tanks but it gave more problems than power so siad a boat expert at my hobbyshop (it will presser the tank some times but if it works than you put the boat in the water that boat will dia when you excelerat becouse the presser from that nippal s to weak if any)

u have to use the header to pressur the tank to have a riliabale engine rpm like on cars and plians
the one on my k&b 35 from the 80's was brass so i just soldered it in
so if you have this and your engine has to be pimend to start and it eats all the fuel in the line but no more than dont feal bad becouse i have had my boat for 3 month i have taken it to a lake 3 times and taken the engine apart more than 15 times but have never had it running in the water intill that holy man at the hobby shop told me this

also check to se if you have eney holes in your tank