7.5 Mercury-tranny problems

Treever

Recruit
Joined
Apr 15, 2003
Messages
5
Hello everyone. I have to admit, I know about three things, and outboard motor repair ain't one of them.<br /><br />I have a 7.5 Mercury-forgot to write down the serial number and I don't know the year. The manual I found was printed in '82, so I think that gets us in the ballpark. This motor came with the boat, which came with the house my wife and I bought last year.<br /><br />The motor had some water pump problems and the previous owner had it fixed for me as a nice gesture. The guy who fixed it is not a marine mechanic by any stretch, but he did fix the water pump.<br /><br />But, and this is the crux of the problem, the motor now starts in neutral but it is in forward gear, it doesn't shift well into forward, and reverse is neutral. To get reverse I have to really crank the shift lever back to barely engage it.<br /><br />Nothing seems to be wrong with the lower unit. I took it off and both the drive shaft and transmission shaft are in good shape.<br /><br />I took the hood off and everything seems to be working on the top end when I move the gear lever.<br /><br />Any ideas?
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: 7.5 Mercury-tranny problems

Hi Treever,<br /> Most likely the shift rod is not correctly aligned upon reinstallation of the lower unit into the exhaust housing. I generally make sure that both the shift handle up top and the shift rod coming out of the lower unit are both in the Neutral position (prop spins freely) and then assemble from there. Test the alignment before tightening up both nuts. You should get a solid lock to lock (approx 120-degree) spin in reverse, and a lock in one direction and ratchet in the other for forward gear...<br />- Scott
 

Treever

Recruit
Joined
Apr 15, 2003
Messages
5
Re: 7.5 Mercury-tranny problems

Thanks, Chinewalker.<br /><br />So, the shift rod...you are speaking of the splined shaft that is parallel to the drive shaft in the lower unit?<br /><br />I think I now might know what happened when the rocket scientist fixed this motor. See if this makes sense.<br /><br />This motor requires that you put the gear in forward to tip it up. If he took the lower unit off to fix the water pump, then put it back on-but with the gear now in neutral-then it wouldn't be lined up correctly.<br /><br />So, I need to turn the shift rod to neutral and have the shift lever up top in neutral to install correctly.<br /><br />Does that seem right?
 

Treever

Recruit
Joined
Apr 15, 2003
Messages
5
Re: 7.5 Mercury-tranny problems

Holy sh*t! I now know something about outboard motor repair. I better go home and call it a day.<br /><br />Thanks for your help. I really appreciate it!<br /><br />Steve
 

Treever

Recruit
Joined
Apr 15, 2003
Messages
5
Re: 7.5 Mercury-tranny problems

It worked. My motor is up and running. Thanks again and I will definitely recommend this site to my friends.
 
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