Logo

Changed a seal.......now BF90 stuck in neutral

https://www.boats.net/catalog/honda/...03/shift-shaft

2003ish BF90

I just replaced a shift rod seal. I removed the seal (29) and seal holder (11), then installed a new seal and seal holder. The motor was in neutral when I disassembled then assembled everything. It certainly felt and looked like the shift shaft (8) was positioned correctly. (I could feel that it was 'in' it's bushing, I 'felt' that it was engaged with #4 shift shaft, and the seal holder and seal went on with out disturbing the position of the shift shaft. Radially it was positioned so it looked like it did prior to disassembly, i.e. shift shaft (8) was in the same neutral position as it was before I changed the seal.


After reassembly: boat is stuck in neutral. Shifting into forward and reverse rotates the shift arm (5), in and out of the detent, seemingly as it did before.

Lower unit was not touched.

Shifted a little stiff but o.k. before this seal job.

The boat was bobbing around in the water with the motor up while the old seal and holder were out and I was waiting for parts......could the shift shaft have rotated on its own? And therefore #4 wasn't in the 'neutral' position when I put everything back together?
 
Seems pretty clear to me something went wrong somewhere on re-assemnly. It's not going to fix itself. You're going to need to double back, pull it down, and see what went wrong. Shouldn't be that hard....

I would start by confirming that the lower unit stays in neutral when disassembled in neutral. My bet in your case is that it did not.
 
Last edited:
Yep, lower unit is in neutral. Won't shift out of neutral as a matter of fact. I realize reassembling is the way to go. I guess I'm looking for a tip to make sure #8 and #4 are engaged properly......you can't see them during assembly. I'm just not sure what I missed or how I could have done it better. Or perhaps there's something about the whole assembly that I don't realize that someone who has had it apart before would.

It's coming out of the water for the year, I'll tear into again and get it sorted one way or another.

Thanks for the response
 
Are you sure ,on the shift shaft ,that the one missing spline is towards the front ,cruising direction .You will have to pull the lower unit, remove the water pump housing ,the shift shaft holder. Pull the shift shaft up and look inside , make sure that collar is centered, and is in neutral. Shove the shift shaft down making sure the missing spline is facing forward, try to turn it in forward and in reverse, replace the holder.
 
Problem is fixed. I'll summarize, this may help someone in the future with the same problem.

Problem: 2003 bf90 stiff shifting, not due to cable, lower end or control box.

https://www.boats.net/catalog/honda/outboard-by-hp-serial-range/90hp/bf90a3-lhta-2003/shift-shaft

I suspected the bushings that #4 and #8 run in were the source of the extra resistance. I removed the seal and seal holder (#29 and #11) and shot it full of pb blaster......I did this a few times and let it set overnight. The boat was in neutral when I took it apart and I noted as best I could the radial position of the shift shaft # 8. That's important, because you can't see at all how it engages with #4 upon reassembly. It's very easy to install 8 and think it's engaged with #4 and it's not (ask me how I know lol). I put a long zip tie on the splined part of the long shift rod that goes down to the gearbox. That allowed me to see whether or not the shift rod moved when i jiggled the shift shaft 8. (because the long zip tie is sticking out far enough that I can see it while working on the front side of the motor) Once I was convinced 8 was engaged with 4, i slide the new seal and seal holder in place, periodically checking that the gears were still engaged. Buttoned it all up an voila, shift smooth as butter now. The proper way to do this is to tear the motor apart so you can access the gears and properly clean and lubricate them......that wasn't an option in this case so I took a chance on a bush-fix and it worked. Make sure you are in neutral before you start and your control box is also in neutral.

extra: I drilled a small hole in the face of seal #29 after I installed it in the seal holder and before I installed the seal holder. In that hole, protruding into the case, is the red tube that comes taped to the side of WD40/PBlaster etc.. cans. It's a tight fit. So now I can lube that area once a year and keep things moving smoothly, I just connect the can to the red tube and give it a squirt. I'm guessing that maybe one of the seals is going bad and allowed some corrosion to form on the shafts where they go into the bushings. Kinda like what can happen to the starter gear and ends up preventing it from shooting out and engaging the flywheel. That's just a guess. Anyway, I feel better being able to maintain some lubrication to #4 and #8

Cheers.
 
Back
Top