fishnfiend
Petty Officer 2nd Class
- Joined
- Aug 11, 2005
- Messages
- 115
1986 Mercruiser 3.0 140 MR Alpha One.<br /><br />Installed new marine starter (one long bolt, one short bolt) this spring. Boat is new to me, so thought slow revs of starter were starter problem. Turns out corroded connections, cable ends, etc. were stealing juice. Replaced slave solenoid. Have excellent voltage at starter when key is turned.<br /><br />Starter has good power and fires engine up most of the time. Motor runs excellent at all rpms. Has good power. Plugs were a little sooty from too rich idle mixture most likely (possibly too rich jets, but runs great at all speeds). No evidence of water in cylinders. Just serviced the manifold assembly (problem existed prior).<br /><br />About every 5th try, the starter "clunks" and moves the crankshaft about an inch. Typically, on the second try then, the motor fires up instantly. Bendix gear is new, shows no wear pattern yet. Ring gear on flywheel looks fine - no missing teeth that I can see.<br /><br />Have read posts addressing shims to better postion bendix/ring gear. Tried a thin shim under engine side of starter. SEEMED to reduce frequency of no spin at start. Then tried a thicker shim, and it "clunked" on nearly every try (still always started second time).<br /><br />My best guess is either bendix/ring gear binding or internal starter problem. How can I best nail this one down? <br /><br />I'm forunate to have easy access - when I rebuilt the boat, I made sure I can get easily to engine from any angle.<br /><br />Thanks for any information, gentlemen.