Hard steering Mercury tiller – not under load

Hi Guys,

I have a 75HP Merc tiller on my boat. This spring, after pulling it from storage, I could not even move the motor left/right because it was seized up. I worked at it for some time and finally got it to start moving back and forth and I cleaned up the stainless shaft that goes through the steering tube (I think that is what it’s called). I used white lithium grease and then used silicon spray after I cleaned it up and wiped it down.

It worked fine up until a few days ago when I didn’t fish for an entire week . I went out the other day and the steering was very stiff again and it is hard to turn the handle/boat to the port side. It seems as though it gets stuck in a specific spot (straight ahead) and once you get past that it is fine. I assume this is because when the boat was stored that is how the motor was oriented.

Any ideas on how to clean this issue up? Anyone know how to take that steering tube apart?

What year? You have a pic?

I had a 98′ 75hp Merc, it had a horizontal metal shaft that went through a housing with a tensioner on the end.

I think there might be a zerk on the bottom side of it if I remember right.

I had something similar on my 2009 75hp mercury.

What helped a lot was replacing that plastic tensioner lock. What u tighten to adjust tension.

Not sure if that would help you but figured I’d mention it.

Sorry, it’s a 1998. Mine has the rod that goes through the tube and I have greased it as well. I guess I am not sure about the tensioner. I guess I will have to dig into that and see if I can figure it out. Is it kind of like a nut on the end of the tube that you can screw down?

royalfish wrote:

Sorry, it’s a 1998. Mine has the rod that goes through the tube and I have greased it as well. I guess I am not sure about the tensioner. I guess I will have to dig into that and see if I can figure it out. Is it kind of like a nut on the end of the tube that you can screw down?

Yes, a little triangle or star knob on the port side of the shaft. It’s plastic like Shocker said, just a small friction device. Similar to a height clamp on a trolling motor.

Do you have any rust on the inner shaft showing? (outside of the housing)

Give the shaft a shot of WD or Fluid Film and see if that helps.

Have a ’98 Merc 90/65 jet and had this same problem. Mercury in their infinite wisdom put an O-ring in the middle of the tilt-tube that has a nasty habit of disintegrating, not a problem grease can fix. I bought a new tilt tube and replaced it, bought an OEM one without the ring as well and just made my own zerk.

^this dude is awesome and can help you diagnose the issue.

On the back of the motor, you should find at least one grease fitting, that lubricates where the motor actually pivots on the mount. I would try greasing that, move the motor back and forth, to get grease to the shaft. I believe that should help.