Compression Test Question

[MisterCinders]

Trying to grasp the basics of this test.

Clymer says to open throttle and crank engine to measure compression. Does that mean using the bolt to turn engine like when rotating valves? Or do I simply open the throttle to check? TIA.

[kdo58]

use the starter

[cowboyup3371]

Take all of the plugs out and crank the engine like you are trying to start it while holding the throttle open. Once the needle stops moving you are set for that cylinder. Move to the next one.

[earlfor]

Trying to grasp the basics of this test.

Clymer says to open throttle and crank engine to measure compression. Does that mean using the bolt to turn engine like when rotating valves? Or do I simply open the throttle to check? TIA.

Make sure the choke is in the off position. Remove spark plugs and put the compression guage on the cylinder you want to read. Hold the throttle wide open. Spin engine with starter. Read guage. The little button on the side of the guage is compression release which resets the guage to zero.

Earl