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4hp Shifting Issue

P

pilot1950

Member
I'm new to the Mercury products here so please be patient. I do tinker with the Evinrude / Johnson small hp products. An older gentleman presented me with a problem. He has an older 4hp single cylinder serial 3766406. I did a search and believe it to be 1974. He says it won't shift into neutral. It was in a dark place so could only do a brief search. However, pulling in through while working the shift lever, it would turn the prop both forward and reverse but when put in the neutral position, it would turn forward. In looking at the diagrams, I could quite figure out what moves the clutch dog on the prop shaft to get forward and reverse. Is there an adjustment somewhere? He says a friend put in a water pump a while back, but that's been quite a while. Doesn't look like any maintenance (or use) over it's life. Doubt the gearcase oil has been changed. Anyway, I'd like to help him out but don't quite know where to start looking. He's probably in his 80's and his great grandkids are really bugging him for a boat ride. Any hints that the group could provide would really be appreciated. Thanks. BTW, he says the engine runs good, just doesn't shift into neutral.
 
Got time to work on this today. Racerone was absolutely correct. I strongly suspect that the shift shaft was not "clocked" correctly, even though I can't confirm it. Pulled pump housing just to check. Impellor seemed intact and flexible. Owner says it was replaced a while back. Greased splines, reinstalled lower unit, checked shift function. Seems to work correctly now. Another potential issue found. Thought it prudent to change the gearcase oil. pulled drain plug and breather hole plug. I'm guessing only around 1/4 cup came out. Color was similar to caramel. Not white and not what I'd call milky. put fresh in there to full capacity. Recommended to the owner he consider having the lower unit re-sealed. Sounds like he only gets out a couple times a year so wouldn't call it extemely urgent but needs attention. Thanks for the feedback. Fun learning project.
 
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