Working on a customer's 2002 115Hp Mercury 4-stroke EFI. Owner said it tried to start for the first time this year it tried to start then stopped and when he tried crank it again it sounded funny.
When I cranked it over it sounded like I was cranking it with the spark plugs out! Removed the spark plugs and carried out a compression test with two different compression testers. No compression on any cylinder! Huh?
I'm thinking the camshaft timing is out somehow allowing valves to be open on the compression strokes. Camshaft timing belt all appears intact and no obvious damage to the valve train anywhere. Next I will remove the flywheel and stator and check the timing belt pulley on the crankshaft to see if anything has slipped or moved. Any other ideas anybody? Remember there is no compression on any cylinder!
When I cranked it over it sounded like I was cranking it with the spark plugs out! Removed the spark plugs and carried out a compression test with two different compression testers. No compression on any cylinder! Huh?
I'm thinking the camshaft timing is out somehow allowing valves to be open on the compression strokes. Camshaft timing belt all appears intact and no obvious damage to the valve train anywhere. Next I will remove the flywheel and stator and check the timing belt pulley on the crankshaft to see if anything has slipped or moved. Any other ideas anybody? Remember there is no compression on any cylinder!
