Hard starting Kohler

[SidecarFlip]

Far as the tapping goes. mine 'taps' too until I increase the RPM and then the ACR deactivates and it's quiet as a mouse. The tapping is the ACR sub cam attempting to hold the valve (intake or exhaust) off the seat by a few thousands and if it taps, it's working fine so you have a valve clearance issue (excessive). The ACR cannot hold the valve off the seat if the clearance is too great.. That is why you have a hot start issue. Lots of compression and quick ignition but no ACR so the motor cannot get past TDC and roll over.

If you feel incapable of removing the valves, any competent shop can handle it.

If you do it yourself, I'd de-carbonize the head (which Kohler recommends anyway every 500 hours) and check the valve seats while you have the valves out. Seats and valves are easy to lap when it's apart.

Make sure you install new head bolts and a head gasket. Head bolts are much cheaper at Fasten-All versus the mower shop. Head gaskets are online at Amazon.

 

[Blackstar]

Sounds the same as as the K241 I have. They way you adjust the clearance on my engine is grind the ends of the valve stems where they contact the lifters. They have to be ground square the the stem and it entails removing the head (s) and renewing the head bolts and head gasket(s). The way you obtain the clearance is use a feeler gauge to check the clearance you now have, remove the head(s) and pull the valves and remove enough material to get the overall length of the vale within the tolerance you require. It's not a bad job but will require you to have a valve spring puller (C) tool, torque wrench and some time.

The only way to check the the ACR is operating correctly is to pull the cam which is in the belly of the engine but I think you have excessive clearance in the valve train.

That sounds like an off season repair job for me. But anyway, I was just back out to the shed and checked if the ACR was working by rotating the engine through it's cycles and just as the intake valve closes the exhaust valves opens slightly then closes again. So this means I have to pull the head?

While I was checking things I noticed that the rockers and pushrods seem very snug. No loose play in anything. Feels like the lifters are pumped up correctly...

 

[SidecarFlip]

The lifters are solid, not hydraulic. The flat end rides the camshaft, the hollow end is where the pushrod fits into. You need to roll the engine over to TDC with both valves closed to check the clearance. Use a dowel rod in the sparkplug hole to determine TDC. Remember is's a 4 stroke so you may have to roll it over 2 revolutions.