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BF75 shift shaft screw up?

A

Alan S.

New member
I have a 1997 Honda 75 hp (BF75) and needed to remove the shift shaft seal housing (lower unit) to replace the seal. Unfortunately, I allowed the shift shaft to lift up as I was prying off the housing and the shaft came out of the shift cam down in the prop shaft housing. I was able to get the shaft back into the cam but it seems like the shifting sequence isn't correct now (neutral isn't between forward and reverse?). I basically want to know if removing the shaft was a major mistake and now have to remove the prop shaft workings to fix it, or if this isn't necessarily the case and I can get back to normal from where I am. Or, if perhaps I'm wrong about the shifting sequence. Also, The motor shifted correctly before I removed the lower unit. Thanks, Alan
 
You should be able to put it back in without removing the propshaft. It sounds like you have one of the mercury gearcases that Honda used when the BF75 was introduced. It is sometimes hard to find the flat spot on the shift shaft.

If there is a way to get the gearcase to neutral...do so. Pull up the shift shaft and look down into the hole. There should be a shoe that the shift shaft goes into. It kind of looks like a little pulley. The pin on the end of the shift shaft should go into the groove of the "pulley" on the right side of the it...as you are looking from the rear of the gearcase to the front.

If the "pulley" is not in the center of the opening, it is probably not in neutral. Take a big screwdriver and reach down and move it so it is centered. Then stick the shift shaft in.

Hope that helps.

Mike
 
Hi Mike,

That sounds like really good information. Yes, the Honda dealer told me it was a Mercury gearcase. I will give your method a try and let you know how it goes. Thanks very much for responding! Alan

hondadude said:
You should be able to put it back in without removing the propshaft. It sounds like you have one of the mercury gearcases that Honda used when the BF75 was introduced. It is sometimes hard to find the flat spot on the shift shaft.

If there is a way to get the gearcase to neutral...do so. Pull up the shift shaft and look down into the hole. There should be a shoe that the shift shaft goes into. It kind of looks like a little pulley. The pin on the end of the shift shaft should go into the groove of the "pulley" on the right side of the it...as you are looking from the rear of the gearcase to the front.

If the "pulley" is not in the center of the opening, it is probably not in neutral. Take a big screwdriver and reach down and move it so it is centered. Then stick the shift shaft in.

Hope that helps.

Mike
Click to expand...
 
Hi Mike,

Things don't look quite exactly as you describe - the shift shaft has a straight spline at the bottom, no pin or anything like that. And, the shoe that it goes into doesn't have a groove. It might have a little "dot" that is indented in the metal but it's hard to tell. I put the gearcase into neutral as you suggested before pulling the shaft out, but neutral puts pressure onto the shoe and it goes flying as soon as I pull the shaft out, and then the gearcase is no longer in neutral. Only forward gear doesn't put pressure on the shoe. Is there any way I can get back to normal in some other gear besides neutral? Also, someone mentioned that the shoe needed to be right side up. I don't know if it flipped over, but it seems difficult for that to happen. Any ideas? Thanks, Alan
 
Sorry for the misinformation...I was looking at the wrong gearcase.

It is hard to tell if the shoe has turned over. I would proceed assuming it has not.

You might try checking which direction the shift rod should turn when you put it into forward. Just look at the shift shaft going up the engines pivot when someone puts it into forward.

Then try aligning the gearcase shift shaft to the same orientation, so they will mesh.

Then try rotating the shift shaft back to neutral if you can. If successful, check to be sure you can get reverse. Put the gearcase and the boats shifter back to neutral and hopefully it is ready to be put back on the engine.

I hope that works...I have never tried it, but it seems like it could work.

Mike
 
Hi Mike, You convinced me to check the shaft rotation at the lower unit. I had previously only checked the direction of rotation of the lever up in the powerhead (since I was by myself and couldn't see the bottom of the shaft while shifting). I assumed they must be turning the same way. Well, I'm glad you brought it up because the rotation at the two ends are opposite of each other! I finally had my wife do the shifting while I looked at the shaft and realized that the sequence of the gear case has been correct all along! I'm a little embarrassed but very happy now. I greatly appreciate you taking the time to help me out and saving me from bringing it to a mechanic in the nick of time. Thanks, Alan
P.S. I haven't finished rebuilding my water pump, which is where this all started, so I hope I'm not speaking too soon!
 
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