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

[99yam40]

you need to look harder at the parts break down.

the clutch dog is on the prop shaft not the drive shaft

[Soundear]

Sorry...mistype.... I was running a bit late and just wanted to post my thought before I went to work. Yes it is the prop shaft - not the driveshaft -that holds the clutch dog. I’m still learning, so any other advice or suggestions are greatly appreciated ..... this forum has been a tremendous resource over the years for me. This is the first time I’ve tackled a fix this deep into my lower unit. Thank you for reading my post and catching that!

[99yam40]

so you realize that with the clutch dog pinned to the prop shaft, you cannot pull the prop shaft without unpinning that,
and only way I know to remover that pin is after the whole propshaft , gear, bearing, and carrier is out of the lower unit housing

did you open the link I posted earlier and look at the parts breakdown?

[Soundear]

I believe I understand the illustration. Correct me if I'm wrong, but isn't the Shift Shaft located furthest inside the prop shaft boot and the Clutch Dog in between that and the prop? I've seen a few You Tube videos that support the fact that by removing the shift shaft rod after the motor is placed in neutral, the Prop shaft easily comes out.. Maybe thats just on certain Yamaha outboards. Once the Prop Shaft is removed, clutch dog components, gear and bearing removals are done. How could you pull the Clutch Dog pin if the prop shaft assembly is still encased in the LU boot. I could be completely way off on my assumptions.... I'm just trying to make sense of it and pull the dam thing out with minimal damage!

[99yam40]

with the clutch dog pinned to the prop shaft, the prop shaft cannot come thru the gear, bearing, and carrier.
so if you have already pulled the carrier, then you just need to pull the prop shaft, gear, and bearing if that did not stay in the carrier when you pulled that.

rig up a slide hammer to thread onto the prop shaft and pop them out
usually it is the carrier that is the hold up

[Soundear]

Thanks for your patience with me! I finally understand what you’re speaking about. I was successful and re-moving the bearing but I am unable to grab the gear to pull it out to gain access to the clutch dog pin. It’s still seems tied into the driveshaft pinion that cannot be pulled out unless you get to the pinion nut. I’m so close - yet still stuck. How would I go about doing that?

[99yam40]

drive shaft and pinion are on the inside of that gear so they are not holding that propshaft from coming out.
prop shaft with the clutchdog and gear should come out.
as I said rig up something to attach a slide hammer to the threaded prop shaft

now if the prop shaft is stuck to the bearing in the nose of the housing or the reverse gear on the other side of the pinion that could cause another set of problems

[Soundear]

Gotcha! I’ll rig up a puller next directly on the shaft. I originally misunderstood your direction and tried to take off the bearing first then the pinion, but now I completely get it! I think the shift slider is Jammed at the nose and has been the issue in preventing that assembly from pulling out. I’m going to push it a bit at the shift shaft opening as the Service Manual indicates with a long stem screwdriver to carefully coax it out. Thanks for the guidance

[Soundear]

I fabricated something to use the slide hammer with using the threads on the prop shaft like you suggested. It's still real stubborn! I sprayed some release agent around the prop shaft and gear in the boot to soak it a bit in hopes it will break free. When I look in the boot from the prop shaft , I see the thrust washer and the reverse gear behind it. The thrust washer seems to be fused to the inside boot. The Gear is free of that washer but still being held in. Do you recommend some heat on it?

I'm beginning to think this was a pre-existing issue when I bought the motor in 2015. The first thing I did before I ran it was drop the LU oil. It was milky so I decided to change out the lower prop seals , water pump and upper driveshaft seals. That whole upper seal area under the water pump was rusty. I betcha a little water made it's way inside the boot and created some problems for me. I'll know more as soon as I finally pull it all apart.

[Soundear]

Update......... The thrust washer behind the reverse bearing was literally fused to the inside rim of the L.U. housing. After days of carefully trying to remove that washer to minimize any damage, I resorted to some map gas in combination with tension on the prop shaft with a prop shaft puller I fabricated. After heating it for a little while, I removed the heat and put some ice on the washer to shrink it and heard a loud "Pop" as the metal washer released. Once off, the reverse gear revealed some missing teeth when I removed it. The small pinion gear at the base of the driveshaft was also damaged and real rusty. I think for a period of time before I owned the motor water sat in the L.U. for some time. Right now, the prop shaft is still stuck in the L.U. with the Clutch Dog on it. The shift slide is positioned correctly for the prop shaft to easily be removed under normal conditions. Once free, I can remove the pinion gear from the driveshaft; replace it and inspect the forward gear in the boot. I think I need to apply some heat once again to free the prop shaft so I can put an end to this whole thing. Anybody have any other suggestions?

[Keithbaja]

Sounders,. I sent u a private message. (I hope) CK it out I can save u a whole lotta grief with this issue

[Soundear]

I ordered a Gear set (Rev, Forward & Pinion); a Reverse Bearing and a carrier "O" ring. The Reverse Gear and Pinion had fractured teeth, I damaged the reverse gear bearing pulling it out, and the carrier O ring flattened out from it's normally rounded shape. I inspected all other items and found no apparent damage or wear. Is it still recommended to replace the other Bearing (Forward), the bearing plates (washers) and bearing races for both as well?

I found three shims and measured them with my Digital caliper @ .30, .30, .15. With new gears, I presume i need to re-measure everything to determine shim sizes and the correct backlash. The service manual refers to several specialty tools. Is it mandatory I purchase all of these specialty tools listed below to successfully replace all three gears and bearings and measure for shims, or is there another way to successfully change everything out without compromise ?
* a Shimming Gauge YB-34446
* a Shimming Plate 90890 - 06701
* a Height Gauge 90890 - 06702
* a Bearing Depth Plate YB-06213
* a Dial Gauge 90890 - 01252
* a Backlash Indicator YB-06265

I already own a Digital Caliper, and assume a Backlash indicator is a must to not damage anything

The values stamped on my Trim Tab mounting surface is as follows: F +9 2x R +2 P -4
I never saw a measurement value of F +9 2x. Do I treat the measurement F +9 2x as F +18 as the deviation of the lower case dimension from standard to determine the shim size for the Forward gear?

[Soundear]

Well, with work and the holidays (not to mention the cold), my outboard has taken a back seat in priority. This weekend, I plan on doing the job. I asked a few questions in my last post about six weeks ago and did not get an answer! I did acquire some tools (a shimming gauge, a height gauge, a dial gauge and backlash indicator) to do the job and have been reading up on the proceedure. The one question I can't seem to find an answer to is the values I found under my trim tab:

The values stamped on my Trim Tab mounting surface is as follows: F +9 2x R +2 P -4
I never saw a measurement value of F +9 2x. Do I treat the measurement F +9 2x as F +18 as the deviation of the lower case dimension from standard to determine the shim size for the Forward gear?

In all of my research, I can't find a situation where anybody an "F" value that after the stamped +/- number, a "2x" followed! Any ideas?

[TownsendsFJR1300]

I've never heard of the "value" and I suspect it's not in the manual.

I'd follow the manual to the letter and you should be good to go..

Sounds like your in good shape for assembly..


*I suspect no one answered the earlier post, for the same reason, never been heard of.
Perhaps a casting # for something else..

..

[99yam40]

I have no idea about those marking either,
might ask you local Yamaha shop tech.
If Rodbolt was still here, I am sure he would have known

Boscoe is the one that usually can dig up info