Lower unit shift rod stiff

[SkiDad]

Hi Guys, i had a lower unit from an 1987 engine that I put on my boat 2 years ago - the shift rod seemed a hair stiff but nothing too big of a deal.

I pulled it this weekend to change the impeller and man that rod is very stiff now - it takes a ton of effort to move it - it's also very hard to rotate. I'm guessing the seal is causing it to be stiff. I don't really want to take it apart - is there something I can spray on it ? I did take it in the house to let it warm up - no difference.

PS - i change the gear oil every fall before storing.

 

[pnwboat]

Might try some WD-40 or other type of penetrating oil on the rod to see if that helps.

 

[tommarvin]

You can try to pull the shifter seal up, I have heard you can push them down to tight when you install a new shifter seal.
On second thought get a new shifter seal, O-rings, check the driveshaft seal for leaks,
It's not that had to change the shifter seal, and check driveshaft seal , look around check everything in side there.
If your going to work on your outboard,you should have a factory service manual, it make's it easy

 

[jerryjerry05]

The normal operation of the boat insures that the gear housing gets dunked everytime.
​The shift rod seal: it gets water around it and galvanic corrosion forms and squeezes the seal tighter and tighter.
You'll need to replace the seal.
The WD might make it easier for a short time but you'll need to fix it.

The seals under $5
You might be able to dig the seal out but be VERY careful you don't damage the mating surface.

You might be able to get the gear housing cover off but be careful the bolts don't strip.
They probably been in there for a VERY long time.
You might need a torch and take your time.

Once it's replaced you'll need to pressure test the lower.

 

[SkiDad]

I did try a tad wd40 but I didn't want to spray too much on there and ruin something - will any sprays hurt getting into the LU ?

I guess I can replace the shift seal - should I replace any other seals under that plate like 54 or 56 or it that not necessary ? http://www.crowleymarine.com/mercury-outboard/parts/1215_9.cfm?mdl=QWINQM

and can you suggest a tool that I pressure test the unit (on the cheap) ?

thanks guys - learning something new every year.

 

[tommarvin]

When the gear housing cover off, check the seal on the driveshaft # 57 ,make sure no gear oil is leaking through it.
Yes, get # 54, # 56, they don't cost much.
I have read, guys pump 5 psi air pressure in the LU, and listen for air leaks .I guess you test it before you put the LU back on for leaks ?

There is a tool for this, it's a pressure/vacuum hand pump gauge, it's pricy ,e-bay may have a used tool ?

 

[wickware]

I used regulated low air psi from the compressor and liquid soap tested my prop seals. Then the 24 hr + and all was ?Bingo?!

 

[SkiDad]

thanks guys for all the helpful advice cover is now off.

Jerry, i got the top cover off - bolts were not stuck - you were right, that seal is the problem it took some effort to get plate it off the rod. Do i push the seal out from the bottom of the plate and press a new one in from the top ?

 

[jerryjerry05]

Yes try to push from the bottom.
​Make sure you clean out the seals seat.
Try to take it down to the metal if possible.
Then when reinstalling use a bunch of sealer so water or corrosion won't be a problem.
Once it's started the corrosion can come back fairly quick.
2-4 years instead of 25

 

[SkiDad]

OK my shift seal came in today - do i need to just press it in or do i need to glue it in someway ?

i also got a few other seals do in need anything on the cover plate before I tighten it back down.

 

[tommarvin]

The late Frank Acampora said you can install a new shift seal to deep / hard, slowly push it in a little at a time until you get the right pressure on shift shaft.
I think he said don't push it in to far because you can't pull it out.
Just put the o ring # 54 a tapered rectangle shape in, I don't remember a seal on the gear housing cover

 

[jerryjerry05]

The seal goes in 1 way and you use a liquid gasket, like OMC's gasket sealing compound.
​You have to make sure the seat is VERY clean and no corrosion.
Make sure NO sealer gets on the seal or the shaft.
Grease it after you do a pressure test.

There is a seal on the cover. It's an O-Ring and that needs to be cleaned and sealed when re-assembling.
You can use grease or the OMC sealer.

 

[SkiDad]

I have some permatex I can use. So you are saying put the gasket compound in the seat of the shift seal?

I have the new oring too. Put sealer on it ??

 

[jerryjerry05]

Yes sealer on the seat if the seal has a mating surface.
The sealer fills in the little holes and grooves so no water/ sand, gunk can get in and cause corrosion and another problem???
​Grease on the o-ring

 

[SkiDad]

thank you guys - it all makes sense now!

do i need to remove the gear oil to pressure test ?

 

[jerryjerry05]

Yes you do.

 

[SkiDad]

i got the seal installed this weekend - seems a little stiff to me - could I have possibly pushed it in too much ?

PS - i cleaned the cover and seat before installing - i pressed it down so seal was flush with seat. I pressed it in while the cover was off. I can do this again if I did something wrong.

 

[jerryjerry05]

Take it back out and clean the area again.
​Using a small amount of a liquid sealer like OMC's gasket sealing compound.
You clean the shift rod? Crud builds up on it.
Grease the seal after installing and then insert the rod.

​It shouldn't be too easy shift.
Remember the gears should be moving when your trying to shift.

 

[SkiDad]

The late Frank Acampora said you can install a new shift seal to deep / hard, slowly push it in a little at a time until you get the right pressure on shift shaft.
I think he said don't push it in to far because you can't pull it out.
Just put the o ring # 54 a tapered rectangle shape in, I don't remember a seal on the gear housing cover

i took some time to redo the seal recently - last one I pushed in way too tight. this time I took this advise above and put the seal on after the cover was on - used a couple of long sockets to tap it in until it seemed right. shifts nice and smooth now. results... just in case this will help someone else

 

[jerryjerry05]

You pressure test?