Did work now shift rod doesn't engage reverse

[vb2oc0371]

2008 Yamaha 25hp 2 stroke

I changed the shift rod lever because it was munged up. That required me to remove the powerhead to reach it. So I did that and put everything back together with the new shift rod lever installed.

Now when I put it in reverse, the lower shift arm doesn't go far enough down to push the clutch dog into place. Seems that somehow I've shorted myself a half an inch out of the shift rods lowering capabilites. Where could I have gone wrong in putting everything back together? Everything looks ok, and there doesn't seem to be any out of place parts that could restrict the movement of the shift arm or shift arm lever?

This is as far as the shift arm goes down when in reverse.

[IMG][/IMG]

[walleyehunter13]

Did you have the lower unit and lever in reverse when attaching the rods together?
I had the same problem when I did my water pump, thought I had it in reverse but you need to make sure you turn the prop in reverse to make sure it fully engages.

Also, while it is super tricky, it is possible to replace the shift lever rod without taking the powerhead out. I just did mine a month ago. Took a lot of wiggles and weird angles but I got it in.

[vb2oc0371]

Did you have the lower unit and lever in reverse when attaching the rods together?
I had the same problem when I did my water pump, thought I had it in reverse but you need to make sure you turn the prop in reverse to make sure it fully engages.

Also, while it is super tricky, it is possible to replace the shift lever rod without taking the powerhead out. I just did mine a month ago. Took a lot of wiggles and weird angles but I got it in.

When the upper and lower shift rods are disconnected, I grasped the lower shift rod with needlenose pliers and pushed down while spinning prop in reverse. The lower shift rod responded by (presumably) pushing the clutch dog into the gears. Still holding the lower rod in place, I put the upper shift rod in reverse and spun the nut down until both rods were connected. Now with the connected shift rods in the reverse position, the prop stops whether I spin it in forward or reverse, which isn't right. Should only stop when I try to spin it forward and spin freely in reverse.

Now, after I take it out of reverse (using the shift lever), I can't put it back into reverse. There's something resisting in the gear box that makes it impossible to shift into reverse using the shift lever.

I'm wondering if there's a shim or gear component out of place in the gear assembly that would be causing the reverse to be blocked after I connected the shift rods then took it out of reverse and tried to put it back in reverse.

[walleyehunter13]

Are you trying to shift with the motor off? Might not be aligned to allow shifting and you would need to spin it some like when you were connecting the rods.
Not trying to sound condescending but just covering the basics as that's the problem 90% the time.
If that's not the problem then I'll leave it to the pro's. Just sharing results when I had the same problem

[Jason2tpa]

I had the same issue when I used to have my '98 25hp. Since you didn't open the gear box, or mess with any mechanics in the lower unit, you can assume all is functional. Joining the shift shaft and drive shaft is tricky. Sounds like you were doing it correctly by using pliers to hold drive shaft down in reverse gear while spinning down the shift shafts barrel nut. The barrel nut itself can extend or shorten the junction, depending on how far up or down the shift shaft the barrel nut is prior to joining.

What you're experiencing is the joined shaft is too short, which is why when you take it out of reverse and then put it back in it won't engage the dog.

Disconnect the junction, keeping the drive shaft pushed down in reverse and shift shaft in reverse, then either spin the barrel nut up or down a few threads before joining to drive shaft. My guess is spin the barrel nut down a few threads prior to joining, therefore lengthening the entire length of both shafts. You'll only need to spin down the barrel nut a few threads onto the drive shaft to test if you have it correctly. Once you find the sweet spot then you can secure appropriately. Good luck.

[walleyehunter13]

I forgot about that too, but figured since it originally was in reverse when he first put it back, figured it was ok.
What I did was, with both lever and lower in rev, screw the barrel nut up so it wasnt pushing down on the lower rod at all, and then once everything was clear of each other I started to thread the barrel down till it grabbed the lower rod itself.

[Jason2tpa]

From what I remember, if you had both shafts in reverse position and then screwed down the barrel nut, reverse would not engage after mocing lever from neutral back into reverse. The barrel nut had to be screwed down 3-4 threads below the end of upper shaft, then move lever into reverse to join lower shaft.

No doubt joining the two shafts is a pain, primarily because of the tight space your having to work with while using both hands.

[boscoe99]

Why isn't the jam nut up against the barrel nut?

The nut appears to be preventing the shift mechanism from going downward. If the nut is moved up into its proper place you will have additional downward movement of the shift shaft available to you.

The hook is preventing the nut, and in turn the shift shaft, from moving downward.

[vb2oc0371]

I still had problems with it shifting and staying in reverse after correctly connecting the upper and lower shift rods. Turns out the reason why it wouldn't fully engage into reverse and stay there was a bent lower shift rod.



I replaced the bent shift rod and now it's functioning as designed. My fault because the shift rod got bent out of shape due to excessive force applied when trying to loosen the seized shift rod connecter barrel nut when I was originally taking everything apart. I should have applied heat as soon as I realized it wouldn't turn without twisting the shift rods.

Thanks for all the input.

[Jason2tpa]

The trials and mishaps of an amateur mechanic...we've all been there. No better lesson than the ones you have to pay for out of your own pocket.

And you're correct. Anytime you get resistance when unscrewing something from a saltwater engine a heat cycle is worth the time.