How tight should a lawn mower spark plug be?
Accordingly, is spark plug torque necessary?
Proper spark plug torque is CRITICAL in today's engines. Always use a torque wrench and the manufacturer's spark plug torque specs! Insufficient torque can result in a plug blowing right out of the cylinder head, taking the threads with it. Too much torque distorts the plug.
Poor Engine Performance
- Misfires.
- Trouble getting the engine to start.
- Slow, difficult acceleration.
Also question is, what happens if I over tighten spark plugs?
An over-torqued spark plug can cause stress to the metal shell, leading to thread damage or breakage. Over tightening can also compromise a plug's internal gas seal or even cause a hairline fracture in the insulator.
Hard Start. The most common problem associated with a bad spark plug in a lawnmower is that the mower is more difficult than normal to start. A push mower may take several more pulls on the starter rope before its engine starts, and a lawn tractor fails to start with the turn of its key.