BrianX128 107 #1 Posted April 23, 2021 I'm not sure how to explain this, but I'll try. The wife's mower is a 417A that has a transplanted K341 from a 78 C161. Runs perfect, tons of power, idles perfect, haven't had any issues since the swap. This spring it's developed a new habit of hating going up hills while the deck is on unless you go very slow, however it doesn't lose power it almost chokes itself out. Will randomly start running with a "tapping noise" for a few seconds and smoke black like it's being over fueled. I can't make it do it on command unless I go up a hill with the deck on at full speed on the hydro, seems to be dependent on the thickness of the grass it's cutting. I know in a way it's not engine based, oil is perfect and I've had the head off the engine to put a new gasket in, piston has next to no slop and valves are good. I can clear it up when it does it by either slowing the hydro or dropping the throttle a bit. I'm wondering / guessing if the governor is over fueling to compensate for the hills and the stress of the hydro. I don't have the big 5 1/4 pulley on, just a 4" on the engine. I broke the 5 1/4 getting it off the old kt17 and had the right belts and other parts to use the standard gear one. I'd think the smaller pulley would be less stress on the hydro and thus the engine but maybe not? I'm just trying to figure out where to look first. I re-adjusted the governor but it seems fine also. It's the same fuel knock you get if you fumble the choke when starting and leave it choked for an extra second or two. 1 Share this post Link to post Share on other sites
pfrederi 17,741 #2 Posted April 23, 2021 Have you checked the float level in the carb...11/64" between float and housing... 3 Share this post Link to post Share on other sites
BrianX128 107 #3 Posted April 23, 2021 Actually I haven't, I'll look at that tonight. Share this post Link to post Share on other sites
pfrederi 17,741 #4 Posted April 23, 2021 10 minutes ago, BrianX128 said: Actually I haven't, I'll look at that tonight. If it is a brass float make sure there is no gas inside it 1 Share this post Link to post Share on other sites
Achto 27,606 #5 Posted April 23, 2021 (edited) Have you changed your air filter lately? If your air filter is plugged this will cause your engine to starve for air when under load. This would present similar symptoms as too much fuel. If your float is set right and your air filter is good, then I would try leaning the main jet out. Try 1/4 turn first, I would not go more than a 1/2 turn. Edited April 23, 2021 by Achto 3 Share this post Link to post Share on other sites
BrianX128 107 #6 Posted April 25, 2021 I checked the float, it seems ok to me. I put a new air filter on, old one wasn't crazy dirty but it won't hurt. It doesn't do it as consistently now, but I can still get it to act up once in a while. I'll try the jet next, hadn't adjusted it since it runs fine in other circumstances. I'm also half curious if my electric fuel pump is an issue. Says it's only 3 psi but I don't remember it doing this last year on the manual pump. Share this post Link to post Share on other sites
