Cub Cadet knocks/pings when engaging blades

[jseneca64]

I have a 2014 Cub Cadet XT1 with a 22hp Kohler engine with 120 hours on it. The engine makes a knocking sound as I engage the blades. Air filter, spark plugs and oil change were done 5 months ago. Gas is fresh. Any idea what could be causing this?

Thanks in advance,
John

 

[ILENGINE]

Make sure the four engine mounting bolts are tight. Doesn't take much to allow the engine to move on the frame. A sixteenth of a turn can sometimes be the difference between tight and loose.

 

[jseneca64]

Ii found the fuel pump was leaking. Spitting fuel out of the hole in the back. We'll see if that is the cause when I replace it.

 

[slomo]

Ii found the fuel pump was leaking. Spitting fuel out of the hole in the back. We'll see if that is the cause when I replace it.

Leaking fuel pump shouldn't make a knocking sound.

Water in the fuel tank, yes. Engine damage as in never cleaned the cooling fins, sure. 120 hours is a long time to not do any maintenance. Low or no oil can make it knock. Wrong oil type. Brick hard grass deposits under the deck hitting the blades. Many places to make it knock. Deck unlevel or tires improperly inflated. Might of picked something up in the deck.

No reason we all shouldn't have clean oil in our mowers. Get a Briggs oil/fuel evac tool. Keep the oil clean.

 

[bertsmobile1]

When you finish mowing turn the engine off then remove the dip stick tube
Knocking when the throttle is opened up fully is a sign of a blown head gasket
Fuel / oil coming out the fuel pump is another sign of a leaking head gasket .