YT3000 won't start without starting fluid...

[StarTech]

With a maybe 0.002" feeler gauge between the rocker lever and valve stem and on compression stroke you can tell if there is an ACR bump and at what time in the stroke .

Just before the engine fully at TDC while turning in normal rotation direction. Also valve are set with piston down 1/4" pass TDC. I usually adjust the opposite valve when one valve is fully open.

 

[sgkent]

sounds like a fuel, fuel mixture, or vacuum leak issue. The starting fluid is ether and it is a substitute for gasoline vapor. It is very explosive so it doesn't take much. Since it starts with the ether, it would appear everything is there except gasoline fumes. If it is old gas, that can make it impossible to start too.

 

[Gord Baker]

Set the valves @ TDC, ignoring the ACR. Set them cold. 0.004-6" . It does sound like a fuel problem. Check needle and seat for operation and flow. Check (remove and clean) ALL Battery cable/solenoid/starter connections. File Battery posts 'bright'.

 

[VRR.DYNDNS>BIZ]

I bet a wooden nickel it's a fuel delivery issue. This time of year people are dragging out mowers with stale E-10 fuel from LAST YEAR.

Clean the cooling fins while you are at it.

I also think it could be fuel. The after fire solenoid on the bottom of the carb when dirty or weak may pull away from its spring loaded fuel shut off valve at 12 volts, but at cranking speed, you only have 9 volts and it may not allow fuel to main jet. once it fires and the starter current is reduced, the solenoid clicks. Test it with a 9 volt battery. Otherwise, it may be not getting that compression relief.