129 CC Hydro rattling and knocking
 

Hi guys, Got a problem. Rebuilt k301 12 hp in a 129 CC that starts to rattle and knock after it gets warm while under load plowing snow. Governor will load up carb then engine will die. After 15 seconds, start it and it throttle's up and will run fine w/no rattling or knocking. It sounds to me like it goes into an advanced ignition state but the timing is set correctly. Will do this some days and not others.:bigthink::bash2: Throttle up real fast to clear any carbon buildup seems to help but not always.:bigthink:. Anybody out there ever have this happen to them and do you know of a remedy. Could the hydro pump be dragging it down or is it in the ignition? If anybody knows what's going on let me know. Driving me crazy! Bob O. out

Sounds like a fuel problem to me. Float sticking most likely. Pull the carb, clean it and put a kit in.

No, the hydro pump isn't the issue. Rattling and knocking could be the PTO though.

129 CC hydro
 

The pto does rattle but this knocking comes and goes. It could be the carb but has new float and throttle shaft w/foam seal on shaft as per Brian Miller of A-1 Miller's repair. Could the pin that activates the points be hanging up?

No, the points pin doesn’t give issues. I guess I shouldn't say it *can't* be, but it's not likely.

Did you overhaul the engine yourself?

I recommend avoiding Brian Miller's site. He is of very questionable chatacter.

129 CC hydro rattling
 

Yep, overhauled myself. Went thru all of it and even removed the grenade gears. There was substantial wear on the shafts and too much slop. Why do you question Brian Miller? Have you heard bad things about him and if so do you recommend someone else?

Yeah.... there are bad things about BM. Check out his arrest records, and time served. Nuff said. I recommend Don Vogt, Dale Merkel and myself on this site if you need info.

Did you bore it? Grind the crankshaft? New rod, piston, rings ect? Did you check piston skirt clearance and ring end gap before assembling?

129 CC hydro rattle
 

Bored .020 over, rod journal .010 under new piston rings end gap and cyl skirt all checked. all within specs. It's using oil like crazy now and can't figure out why. Maybe I used it to hard when pushing snow. Don't know how much the K301 can take but I work hard sometimes.

I don't think you can "work it too hard" no matter what you do, other than running it out of oil, running it too lean or letting it overheat due to a mouse nest inside the tins. These engines are basically bullet proof.

J-Mech's probably nailed it on the fuel issue. Next time it tries to die, pull the choke and see if that helps momentarily. If it does, they you've likely confirmed a fuel supply issue. Running lean can cause a knocking sound if I'm not mistaken.

129 CC rattling
 

Thanks, will check out the fuel filter and the carb. As I think about it you guys could be right.

Did you shim the cam end play to spec?