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BF150 lower unit shift rod seals

Ken A

New member
I had water in oil so I had a local shop pressure check & they replaced the seals in my 2004, BF150, lower unit along with water pump.
I still have milk so I decided to do it myself. I drained and pulled the lu, applied about 10-13 psi and found a leak around the shift rod spline at the holder. I pulled the rod holder and found there was no spring ring around the lower seal! The seals were installed in opposite directions. My Honda manual doesn't say which way but shows a cut-out diagram which looks like both seal spring rings are in the same direction, which is UP, outward of the gear case. I thought the spring on the bottom seal would have been pointing down facing the oil and the top one facing up toward the water. This is how it appears they are installed on the Prop shaft.


The manual is BF135A-BF150A, Issue date: January 2008. Page 14-10 for shift rod seals and page 14-22 for prop shaft seals.

Appreciate any help!!
 
Actually I just want to clarify that I'm interpreting the manual picture correctly! If someone else with that manual agrees!!:rolleyes:
 
Both in the same direction with spring rings up, as you are interpreting.

Another way to look at it, when you put the seals in, you will see the flat part of the seals as you put them in.

Also...make sure that the shift shaft at the point where it goes through the seals is smooth and a groove is not worn into it. If so, you will need to replace the shift shaft.

Mike
 
Thanks very much Mike. I'm sure glade you mentioned another way to look at it. Because I would have put them in backwards! The open side of the seal (where you can see the spring) will be facing down towards the oil. Am I correct?
 
No. Remember, you install the seals to the underside of the holder. So, after you press them in, you have to turn the holder over to install the holder onto the shift shaft.

Mike
 
Whoops! Cancel everything I said. I was looking at the wrong seals.

Both seals should be facing the same way with the flat side down and the spring side up as you put them in. I was thinking that they go in the bottom side, where they go into the top.

So, when you put it all back together, you will see the shift shaft coming up through the holder and you will see the springs around the shift shaft.

The part about the worn shaft was the only correct thing that I said.

Sorry for the misguidance.

Mike
 
No problem Mike! Thanks very much for the guidance. One of my deep sockets just fits into the rod holder hole so I'm going to use it with a lil soapy water to press them in. I'll also check that shaft for groves. Thanks for pointing that out.

Ken
 
Well now I'm waiting on a new shift rod.:( The shaft is marred topside just below the spline and then a little bit further down. Doesn't look like wear. Looks like sloppy maintenance. I bought the boat/motor used and relied on a local shop to rebuild the lower unit. My bad. I'm learning how to do this stuff myself.
 
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