Suddenly, It's really hard to shift into Reverse on my 1998 Yamaha C115 2 Cycle

[Soundear]

Hi All!
After a great day out with the motor, I pulled in as usual to dock @ idle in forward; shifted to neutral - then tried to shift into reverse to stop the boat to park it. For the first time, I experienced tremendous resistance with my 703 Remote control box. I suspected the cable clips popped on the motor end, but was wrong - they were secure. I suspected it was time to change out the remote cables (I'm using the cables I purchased the boat with in 2014) but after removing the control shift cable end from the motor, my 703 worked smooth (no binding or evidence of cable wear) I was able to manually shift the motor quite easily to forward and neutral at the motor linkage; but reverse was so difficult to shift to that I thought forcing it was a bad idea.

At this point, I realize I need to pull the lower unit and inspect the shift rod to see if that seems as stiff as the motor linkage to slowly work my way down to the shift cam and / or dog clutch that after years of use could be warn and of need of replacement. Does anybody have any suggestions on how to pinpoint what the potential problem could be short of removal and visual inspection of the gear case ? It just happened today on a fishing trip, and first thought to post on the forum first. I'm hoping to fix the job this weekend. I do have a service manual, Clymer and Seloc books to scour for troubleshooting next. This forum is usually my first choice because there's nothing that comes close to the value of an experienced marine mechanic who sees issues like these regularly and may be able to offer a valuable approach to troubleshooting and fixing it.
Thanks!

[99yam40]

only time I ran into something like that was a cable going bad.
inspect them carefully where they bend and try not to bend then very far

[panasonic]

Disconnect the linkage on the leg as if you were going to remove the lower unit. Now try and shift. It may be the linkage under the powerhead or something loose has fallen down in the pan under the engine.

If it shifts OK disconnected from the LU....then back into that LU you will have to go. You should be good at that by now...

[Soundear]

Thanks 99yam40, I'll check the cables again but find it hard to believe the cable is the issue if when disconnected, I can't shift it manually! Thanks Panasonic, on this motor unlike others, the shift rod top at the head is splined and does not require any under the powerhead linkage disconnect to remove the LU. Your suggestion lit a light bulb in my head to unbolt the lower unit and drop it an inch or so to disconnect the shift rod spline to linkage to rule out the power head linkage as the culprit as you suggested. Like you said, after that.... it's into the LU I go!

[99yam40]

I had a cable with cracks at the motor end, that apparently allowed water intrusion and rusted inside. hard to move only when hooked up and in a bind.
disconnected it moved freely.

but your idea of dropping the lower to disengage sounds like a very good .
might try holding a little pressure on the mechanism at motor if you do not find anything

[Soundear]

It's really odd! I took off the motor cover since my last post to check the linkage under the head first before I drop the L/U, and now it's shifting smooth....no hard shifts or gear grinds! Question: If after I disconnect the control cables and by hand try to "dry Shift" or push the shift linkage at the motor head toward the back of the engine cowl for forward; center for neutral; and pull the shift linkage toward the front of the engine cowl to engage reverse, should all three positions be as easy to engage as the other? I checked the gear engagement in Forward by lifting the engine, shifting linkage from neutral to forward (push back), then checking the propellor is locked in gear. When I try to pull the linkage toward me to engage reverse, it seems as if the amount of force I'm applying is way to much to continue pulling in fear I may snap something. As I look at the simple mechanics of the shift linkage assembly under the powerhead, it appears to move as freely in both directions.My next move will be to disassemble the linkage under the head; clean then grease it, then re-assemble. Maybe that will reveal the possibility that may have a linkage bind somewhere under the head due to a pivot point / bushing wear.

[TownsendsFJR1300]

Just an FYI, ALWAYS rotate the prop when shifting (when the engine is not running).

You can damage the LU forcing it to shift if things aren't properly aligned inside the LU..

I'd disconnect the shifter cable at the engine.
Then, crank up the engine (on muffs), and see how it shifts (manipulate the engine shifter by hand) with NO cable attached.

If it shifts fine, you know it's NOT in the LU but cable(s), etc...
.

[99yam40]

I believe most of these motors are spring loaded to forward gear.
you have to overcome the spring pressure to get it into neutral and reverse.
And like said above the dogs have to align properly

[Bluefish]

Just a though assuming you have been tilting the motor up and down during all this, as someone stated before something might be rolling around in the pan and was jamming you up might be worth a close look around since its shifting free now

[Soundear]

Great ideas! My problem seems to be on and off! It makes sense that something could be rolling around. I do move the prop prior to dry shifting. It just seems to be a reverse issue only. Because it’s intermittent, I think my first move will be to look closely at the linkage assembly under the head. If I find nothing suspect, I’ll try to disconnect the cables, start the motor and shift by hand to rule out the LU like TownsendsFJR2300 suggests. I’ll update as soon as I can do it. The rain in Florida waits until my weekend off to release, delaying my plan to fix this! Thanks to all for the suggestions!!

[Soundear]

So......... I took the front carb cover off to access the linkage under the carbs to inspect and clean. It looked pretty clean - nothing was preventing the shift mechanism from working. I put some Yamalube on the pivot points of the gear shift assembly and re-assembled it. Not seeing anything suspect, I decided to change the control cables out being I never did since I acquired the boat in 2014. It seemed as if I found my "hard shift into reverse problem" since.
Just yesterday, I started the motor - sparked right up and sounded great! I heard a consistant, mechanical sound not quite as high pitched as a motor lifter "Tick" or low pitched as a piston "Knock". It was subtle and detectable in neutral, forward, reverse, and most audible at a low speed. I ran it for about 15 minutes 3/4 throttle and heard no apparent abnormal noise. As I returned to "no wake" speed, I heard the re-emergence of that "tapping" sound. I shut the motor down, took off the flywheel cover, and inspected everything within the motor cowl looking for what I hoped would be something loose. I saw nothing, so I headed home at 1/2 throttle for a short run to get home to determine the problem. About a minute into the ride, that tapping sound got loud enough to be heard with the motor RPMs up. I immediately slowed it down; shut it off and used my *****ing Motor to get back home. Trying to rule out a piston issue, I decided to remove the spark plugs and do a compression check on each cylinder. My Clymer book indicated a PSI reading of 135 for my C115 - which I thought was rather high. All 4 Cylinders were very consistent in that they came within 1PSI of 90PSI. I did buy a Harbor Freight Compression tester; used it for the first time, and don't really know how accurate it is. I do have a friend that has a "Snap On" compression tester I asked to borrow to recheck and verify. Being the PSI was consistent between cylinders and the motor starts on a dime and ran smooth, I don't think it's a powerhead issue.
I changed the lower unit oil to find absolutely no water (finally!!) in the lower unit, but did find a small collection of metal dust at the magnetic tip of the lower screw. I just began looking through my service manual and Cylmer repair manual for potential places to look next. I don't know if it's a gear shift (dog clutch) issue or something else possibly in the gear case housing making a racket. I value the opinions of the senior members of this forum foremost which was the reason why I posted my issue today. Suggestions?

[TownsendsFJR1300]

So the hard shifting issue is now fixed? And did you have to lower / drop the LU at all?


Lastly, with either a stethoscope, or large handled screw driver you should be able to narrow down the area of the noise.
With the screw driver, put the handle to your ear, the screw driver to the block (or LU if that's suspect) and you should be able to hear where the knock is the loudest.


Probably going to have to do that with the Lu in a tank of water or it'll be too loud to hear anything..

.

[99yam40]

you could drop the lower unit to eliminate that and hook a water hose to the pipe to power head and turn on water so you can run the motor.

A mechanics stethoscope might help pin point where the knocking comes from

[Soundear]

My original Hard shift to reverse issue appears to have been eliminated between cable replacements and greasing the shift assembly under the head. I just pulled the lower unit off to bench it and inspection it. Prior to unbolting it to remove, I first removed the prop and noticed some rubber sticking out inside the castle nut area of the LU boot. With a pliers, I pulled out my Exhaust Gasket all twisted up in that exhaust area around the front of the LU carrier twisted up but completely in tact!!!!
I like the idea of starting the motor with some water in the motor intake pipe with a hose to see if my noise originates at the powerhead or not....

[TownsendsFJR1300]

Well, that's a first about your exhaust gasket trying to exit that way...

Was it you that kept having problems with the LU getting water inside it?


I don't know off hand but I'd assume that exhaust gasket should be pretty taught to keep it in place.

A major exhaust leak can make some odd noises, especially if a loose part is bound up somewhere.....I'd replace that with a new one, re-assemble and then check again..

.