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2003 merc 115 hp efi hard to shift into reverse

E

eric80

Regular Contributor
Hi
My 2003 merc 115 efi is hard to get into reverse.
I've been looking at Youtube vids and my Clymer manual with no success

When i unhook the cable from the motor the helm control works fine i.e. no binding.

when I manually push the shifter pin (see pic with my finger) that goes into the motor it's a bit stiff going into reverse but usually clicks in fairly easy, some times i have to have the right pressure and angle to get it to shift. Should this pin move into reverse as easy or similar as it does to neutral and forward? If not what would the fix be?

when i do pull this pin from reverse into neutral it usually shoots to forward bypassing neutral ie the pressure.

motor in good condition, fluids changed annually and gear oil as well. has had a bump on the lower gear box years ago. pressure tested it and it's fine.

any thoughts on why it's so hard to get into gear?

Up date, I found a few more videos. when i do get the motor into reverse it stays there as it should. it's just getting it into reverse that is hard.
the latest vid i looked at talks about dog clutches. and talks about the motor coming out of gear which mine does not
could there be something else impeding my linkage?
ie drop the leg and put it back in?

throttle shift pin to motor.JPGthrottle shift linkage.JPGthrottle shift pin to motor (2).JPGthrottle shift cables.JPG
 

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The Reverse gear is nothing like F nor N. It consists of 6 rectangular "cogs" and 6 rectangular sockets. The owners and service manuals both caution you that you do not shift into Reverse unless the engine is running or if not running, you are carefully moving the shift lever to R while you are turning the prop by hand to get the cog/slot alignment so that the lever will move the full distance.

It cautions that damage to the shift linkage can result if you force shift without the above precautions. You may have done just that.
 
Texasmark said:
The Reverse gear is nothing like F nor N. It consists of 6 rectangular "cogs" and 6 rectangular sockets. The owners and service manuals both caution you that you do not shift into Reverse unless the engine is running or if not running, you are carefully moving the shift lever to R while you are turning the prop by hand to get the cog/slot alignment so that the lever will move the full distance.

It cautions that damage to the shift linkage can result if you force shift without the above precautions. You may have done just that.
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Hi Texasmark

thanks for that. I had no idea.
are you able to suggest a fix or what i might be up against? I live 2 hours away from my closest shop and though i made an appointment today it's not till Aug 24.

you say shift linkage....in the lower gear case? somewhere else?
 
First thing I would do would be to disconnect the remote shift cable at the engine. Put the engines shift linkage in N with one hand and free spin the prop with the other. Should work just fine.

With one hand start moving the shift lever toward R slowly while you move the prop back and forth with the other hand, just movement and see if you can feel the slots and cogs trying to line up. I would move back and forth once you think you have contact to get a feel for hitting and missing alignment.

Then I would move toward engagement and once you think you have it, start advancing the shift lever farther toward R while wiggling the prop....feeling your way in that you think you have them lined up and they are engaging. Once you first feel you are engaging, mark a spot on the shift linkage and something that doesn't move so that you have a reference line for first engagement.

Continue to advance the shift linkage in the R direction until the linkage stops moving. Grasp the prop and put pressure with both hands on the prop blades and force the crankshaft to turn back and forth...maybe a 1/4 revolution in both directions....just assuring that you have the prop locked to the driveshaft.

Look at your marks and determine how far apart they are....say 1 inch?

Go back to N gear with the shift lever and rock it back and forth to find the center of N movement. Mark that spot like you did in the steps above. Move the shift lever to full F gear. Did the mark move 1 inch also or more or less? If it moved reasonably the same distance I would say that your engines shift linkage is ok. If it didn't, like the R direction moved significantly less than F direction then it's time to tear into it and find out where the linkage (my guess) is bent.

Post back.
 
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New to the forum but I have a similar issue. I recently changed my bearing carrier in my 2000 90 hp stick steer. Not sure if I changed it the correct way but I pulled my prop, unbolted the bearing carrier, and removed the shaft along with the carrier, a flat bearing behind it, the reverse gear, clutch dog and the deal that goes in the end of the shaft that operates the clutch dog...all coming out at the same time. I cleaned parts then installed the new carrier and everything else back as it was. Clutch dog wasn’t removed from shaft. When I put it all back in the foot it slid right in and bolted up. Now....when I’m in forward position my prop spin cc and ratchets at cw. When I move the shifter to the neutral position there is no change at all- very easy to move and the prop still turns the same. When I place it in reverse, it’s actually in neutral and prop free spins. My shift cable/rod bottoms out where reverse use to be but now is neutral. So forward and neutral- prop spins cc. Reverse is neutral. I’ve taken this stuff in and out like 4 times with same results. When I have it all out, If I push in on the deal that operates the clutch dog it moves the clutch as it should to reverse. I reinstall everything into the foot with the shifter in forward so it slides right in with no pressure on the clutch dog. Not sure if I need to do as stated above and shift it as I move the prop or if you guys may notice another issue. Any help would be appreciated. I just hate to have my boat in the shop for 4 weeks. FYI. The engine has been off the entire time.
 
The doodad sticking out the front of the prop shaft is the "cam follower" It moves in and out against spring pressure to position the clutch dog in FNR positions as selected. Obviously F is the least pressure on the follower/spring as the dog fits into the rear of F gear. Following along, mid position the dog touches neither gear and full pressure forces it into the R gear mounted in the bearing carrier you mentioned.

The shift shaft at the front of the LU is splined into a flat plate with 3 oval depressions and is the shifter cam. The cam follower mentioned above positions itself in one of these depressions as you rotate the shift shaft. The angular position of the cam has to be in sync with your remote control position. Apparently you moved the shift shaft/cam while the prop shaft was removed.

I like the center position as you can test where you are with F in one direction and R in the other. I don't know how you would correct your problem without backing the prop shaft out enough for shifting surfaces to clear oneanother, (aka removing the prop shaft somewhat), centering the shifter cam in the N position and reinserting the prop shaft, expecting to have some resistance as you depress the cam follower spring.

Then I'd slide the prop on for a minute and check that the prop spins freeely, then with pliers, move the shift shaft stub in both directions and ensure that F gets you clicks and locks, and rotating the prop while moving the shift shaft stub, when the cogs and slots in R line up and the stub can complete the movement, you are locked to the prop in both directions. If that checks, return the stub to the N position, ensure your remote control is in the center of N position and reinsert the LU.
 
eric80 said:
Hi
My 2003 merc 115 efi is hard to get into reverse.
I've been looking at Youtube vids and my Clymer manual with no success

When i unhook the cable from the motor the helm control works fine i.e. no binding.

when I manually push the shifter pin (see pic with my finger) that goes into the motor it's a bit stiff going into reverse but usually clicks in fairly easy, some times i have to have the right pressure and angle to get it to shift. Should this pin move into reverse as easy or similar as it does to neutral and forward? If not what would the fix be?

when i do pull this pin from reverse into neutral it usually shoots to forward bypassing neutral ie the pressure.

motor in good condition, fluids changed annually and gear oil as well. has had a bump on the lower gear box years ago. pressure tested it and it's fine.

any thoughts on why it's so hard to get into gear?

Up date, I found a few more videos. when i do get the motor into reverse it stays there as it should. it's just getting it into reverse that is hard.
the latest vid i looked at talks about dog clutches. and talks about the motor coming out of gear which mine does not
could there be something else impeding my linkage?
ie drop the leg and put it back in?

View attachment 27582View attachment 27584View attachment 27585View attachment 27586
Click to expand...

as has been covered,reverse gears are straight cut and the engine needs to be running for it to go in to reverse. Check the play in the engine mounts and steering tube, if any of those parts are worn, it can be difficult to shift into reverse
 
HI TexasMark

I followed your directions and they worked.
I'm shifting into reverse quite easily now.
thanks
When shifting into reverse should i be getting some engaging sounds? sounds like it wants to engage, then does with a bit of a clunk.
I've heard this is normal on my era motor but thought I'd check.
also, my barrel adjuster is rotated almost all the way forward, only about 4-5 threads before it will stop.
I've adjusted it using a Clymer manual.....the same manual that said test the throttle while motor is not running to see if it will go in reverse....
since the manual is incorrect re checking for reverse I thought i'd ask about the adjustment

cheers
 
I wouldn't worry about being at the end of the adjustment range if everything is working to suit you. If it wasn't suiting you then I'd investigate, but personally I would leave well enough alone. On the clunk if you are talking about the engine running at idle and you shift into R and it clunks, maybe your RPMs are a bit high. Seems 675 is a popular number in F gear, boat in the water and moving. That equates to about 850 in N. The idea on idle RPMs is slow enough to stay running when you shift into a gear but no faster to avoid the clunk.

The white nylon knurled knob on a SS shaft with a lock nut on your vertical throttle lever arm is how you set idle on a 2 stroke carb...you vary the timing, which is in the vicinity of TDC, give or take a few degrees. Don't know the process on an EFI....may be the same.
 
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Texasmark said:
I wouldn't worry about being at the end of the adjustment range if everything is working to suit you. If it wasn't suiting you then I'd investigate, but personally I would leave well enough alone. On the clunk if you are talking about the engine running at idle and you shift into R and it clunks, maybe your RPMs are a bit high. Seems 675 is a popular number in F gear, boat in the water and moving. That equates to about 850 in N. The idea on idle RPMs is slow enough to stay running when you shift into a gear but no faster to avoid the clunk.

The white nylon knurled knob on a SS shaft with a lock nut on your vertical throttle lever arm is how you set idle on a 2 stroke carb...you vary the timing, which is in the vicinity of TDC, give or take a few degrees. Don't know the process on an EFI....may be the same.
Click to expand...


but personally I would leave well enough alone. it's working way better than before and I'm keen to not fix what's not broken.
On the clunk, i'll have a look at the rpm when I'm out next. thanks

IMG_8219 - Copy.JPG
 
eric80 said:
but personally I would leave well enough alone. it's working way better than before and I'm keen to not fix what's not broken.
On the clunk, i'll have a look at the rpm when I'm out next. thanks

View attachment 27716
Click to expand...

Is that a Halibut? If so, I have had the delicacy here in Sea Food Shop, matter of fact in the sea food shop where myBIL worked to pay his and my sister's college tuition.....superb. We have Flounder in the Gulf of Mexico that must be of the same basic gene, your picture would look just like one without the block and tackle and you in the picture.....lying flat on a table, just more in the 1-2# class. Still a great eating fish but Halibut I'll take hands down.
 
Texasmark said:
Is that a Halibut? If so, I have had the delicacy here in Sea Food Shop, matter of fact in the sea food shop where myBIL worked to pay his and my sister's college tuition.....superb. We have Flounder in the Gulf of Mexico that must be of the same basic gene, your picture would look just like one without the block and tackle and you in the picture.....lying flat on a table, just more in the 1-2# class. Still a great eating fish but Halibut I'll take hands down. College can be tough, right? One of the biggest challenges I face while studying is managing my time effectively. There's so much to do between classes, assignments, and extracurriculars. Sometimes, it gets overwhelming, and I find it hard to keep up with all the academic demands. That's when I turn to EssayLab https://essaylab.com/write_essay_for_money for help. They offer essay writing assistance, and it's been a lifesaver for me. Their service has saved me time and stress, allowing me to focus on other important aspects of my college life. If you're struggling with academic tasks, check out EssayLab for professional support!
Click to expand...
Oh, that looks like a Halibut, and it's indeed a delicacy! I've had the pleasure of trying it at a local seafood shop, and it was superb. I can see the resemblance with Flounder we have in the Gulf of Mexico; they must be from the same gene pool. Flounder may be smaller, around 1-2 pounds, but they're still great eating fish. However, when it comes to choosing between the two, I'd go for Halibut hands down. It's a delightful treat worth savoring!
 
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