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1986 Mercury 35 HP Not Locking Tilt in Reverse

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aMeyers11

New member
After changing the water pump I have found that my motor doesn't engage the tilt-lock in reverse, or in any gear for that matter. I know this is likely something to do with the ramp-like cam in the lower unit. I pulled the lower unit off and found that the cam does not seem to be in the right position. The ramp is pretty much at the bottom in neutral, so the lock is not engaging in any gear. I know you can turn the shaft to go through the gears, but I don't understand how to possibly get this cam to align correctly to the required gear without removing it from the splined shaft?(Is this even possible?) Here is a picture of the cam with the gearbox in neutral. I hope what I'm trying to describe makes sense, any help is appreciated, thank you!


Picture:

https://drive.google.com/file/d/12G--q4EZu-d-2UBiMizFhdz9-V5E3xdX/view?usp=sharing
 
In the image I can see that the cam will only go on in one position which it is, so the problem must be with the other cam that rises up and engages the R lock unless you aren't in neutral. Follow these instructions to find neutral:Turn the LU shift shaft by hand counter-clockwise until it
stops, then with Vise Grips tight on the bottom of the shaft turn it a
few more degrees CCW until it clicks into a stop, this
should be neutral - check by turning propshaft --
prop should spin freely.
Put control in N and go ahead and attach LU to driveshaft housing some turning of the flywheel will help the DS splines align.
Do not shift into reverse unless you turn the prop at the same time.
 
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Thanks for the advice!

I'm thinking it may be an issue with that other cam you mention? When I had the lower off to take that pic I confusingly went between the gears using vice grips not really understanding what turning clockwise/counterclockwise did. Anyways, I eventually got it to thunk back to neutral (prop spinning free both ways). I made sure the gear selector was in neutral and reassembled. Same problem as before, shifts forward and reverse good, but doesn't lock the tilt in reverse(or any gear). I'm thinking you mean part no 93336 1 ? I'm not sure how to adjust that properly?
 
I'm starting to think the cam is supposed to slide off the splines for adjustment, but mine seems to be very stuck on there. I know its hard to tell in the picture, but there is splines evenly around that shaft, so I think if I could slide off the cam I could put it in the correct orientation depending on what gear the lower unit is in. I understand the shifting between the gears, I just don't see how the cam could ever line up without re orientating it.

Here is the line to the cam. I feel like it should be removable, but mine is really stuck and im too afraid to pull too hard on splined shaft

https://www.marineengine.com/newparts/part_details.php?pnum=MER43308T+1
 
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I reexamined the image closeup and yes you can move the cam into a different position - put a screwdriver under the cam in a location that you can pry on it then pry up while lightly tapping on the top of the shaft - but be careful don't pull that shaft out of the LU
these instructions are for 1970's motors but should apply. Was the R lock working before you removed the LU?
reverse-lock-1975.jpg
 
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I replaced the impeller and I believe I mistakenly took that cam off for some reason and didn't put it back on the splines in the correct orientation. The reverse lock was working as it should before I did this lower unit work, so it was definitely something I messed up. Now that I understand I can take it off and re-orient it I should be able to get it working again. That diagram is super helpful! Thank you so much!!!
 
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