Wheelhorsedairyfarmer 13 #1 Posted July 6, 2013 Alright guys. Need input here. K321 following carb rebuild, complete and thorough cleaning, needle valve cleaned out with air, fresh gas in the tank, fuel line and new filter, gas cap properly vented carb float properly adjusted. Alright, I just wanted to throw that out there so I can avoid having to answer all the basic questions. Now what happens is, I start up the mower just fine in the garage. Mow for about 10 or 15 minutes, starts sputtering, corrects for about another 10 minutes at half choke, then sputters more, then it will run another 10 minutes at full choke then just die. My conclusion is that it may be the fuel pump, when I pull the line off the carb and crank the engine, yes I do get fuel coming out the line, however it doesn't come as quickly as it does on my 310-8 or charger 12. Make sense to anyone? Share this post Link to post Share on other sites
953 nut 55,041 #2 Posted July 6, 2013 Sounds like the pump to me too. Share this post Link to post Share on other sites
Wheelhorsedairyfarmer 13 #3 Posted July 6, 2013 Will a K241 pump fit on the K321? I can check it out that way. Share this post Link to post Share on other sites
squonk 41,017 #4 Posted July 6, 2013 Maybe or put an electric pump on and be done with it. No more starvation problems and instant fuel system priming. Share this post Link to post Share on other sites
953 nut 55,041 #5 Posted July 6, 2013 Yes the fuel pumps on "K" and Magnum 8 hp to 14 hp are all a bolt up interchange, I prefer the old pre 1966 pumps that have the primer lever, have them on all my including the GT-14 and 312-8. Share this post Link to post Share on other sites
MarkPalmer 81 #6 Posted July 7, 2013 Yes the fuel pumps on "K" and Magnum 8 hp to 14 hp are all a bolt up interchange, I prefer the old pre 1966 pumps that have the primer lever, have them on all my including the GT-14 and 312-8. Scratch the 8 HP pump from the list, it is different. The 10-12-14-16 HP "big block" mechanical pumps are the same. -Mark- Share this post Link to post Share on other sites
stevasaurus 22,701 #7 Posted July 7, 2013 I had that problem on a C 121...turned out a white spider got caught in the pet cock under the gas tank. It was causing the gas to flow slowly. What you have happening is the gas in the line, fuel pump and carb bowl are full after sitting for some time. When you start it, it runs OK until you use that gas and then the gas flow can't keep up. Check out the bottom of the tank and the pet cock. Hope that helps. Share this post Link to post Share on other sites
Wheelhorsedairyfarmer 13 #8 Posted July 8, 2013 Replaced the petcock and the rubber bushing that goes around it too. However.....I'm gonna check it just in case something is blocking the hole. 1 Share this post Link to post Share on other sites
Wheelhorsedairyfarmer 13 #9 Posted July 9, 2013 Well.......after replacing the fuel pump..........the carburetor got torn down again.......one piece of dirt. One.....lousy......piece.....of........well you all get the picture. Next time I'll be a lot more thorough. 1 Share this post Link to post Share on other sites
KATO 115 #10 Posted July 9, 2013 :handgestures-thumbupright: Share this post Link to post Share on other sites
Wheelhorsedairyfarmer 13 #11 Posted July 10, 2013 Was almost like a very tiny piece of wood or something. I mean tiny tiny. I used a little pin to get it out with. 1 Share this post Link to post Share on other sites