Shifts forward fine, Grinds in reverse

[bigbroncoxlt]

Long story short. Boat is an 88 Sea Sprite. 2.5L alpha 1. The original outdrive was damaged by the previous owners running it without oil. I limped it along for awhile untill the input seal began leaking. No point in repairing a junk drive.

Fastforward to lastweekend. I bought a complete upper and lower from a local boatshop. Everything seemed great. Put boat in water and it didn't want to enguage in reverse without grinding. Quick bump of the throttle and away we went in reverse but it was popping alittle. Forward would grind alittle more than it used to, but no big deal. Ran the boat for a max of 2 hours that afternoon with out any issues other than what I thought was going to be a simple shift cable adjustment. Reverse was only used to launch and to back away from the dock.

So today with the boat in the driveway, shift into forward and adjust cable. All seems well. Shift into rev. and with the cable off the shift mechanism and me pulling the cable as far out as possible the prop will do its normal ratchet when turned counterclockwise, but when you turn it clockwise it feels like it locks but apply more pressure and it will skip.

I can turn the engine over with the prop when its engauged in forward. Does this sound like the shift dog is damaged, or is there something I am missing? Cable moves freely and I had no shifting issues with the original drive.

 

[Don S]

Re: Shifts forward fine, Grinds in reverse

Have you tried adjusting the shift cable the way the OEM manual discribes?

 

[RCAF_FB_FHDOG]

Re: Shifts forward fine, Grinds in reverse

Is somebody else rotating the shaft while you are pulling on the cable?

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

Don, the way I was adjusting the cable was to have my son turn the prop the correct direction, Forward first. Once prop was locked into place I adjusted the barrel, Then I did the same for reverse while adjusting the slide stud on the shift lever. I did this twice to verify adjustment and then started it and ran on muffs. Shifts to forward like a dream. Reverse SUCKS. It will shift into reverse in drydock, but it grinds instead of just catching and going like it should.

 

[Don S]

Re: Shifts forward fine, Grinds in reverse

If it won't adjust, then the lower shift cable is probably worn out and creating too much free travel in the cable. Therefor you can't get full travel in the drive for BOTH directions.

 

[RCAF_FB_FHDOG]

Re: Shifts forward fine, Grinds in reverse

The mounting stud on the syncronization lever ia adjustable. As you move that stud closer to the mtg. stud for the upper cable, you can gain more reverse direction adjustment.

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

Don, if it was the cable, would I not have had the issue with the old drive? I adjusted the cable again today by the manual and it seems better, but its still not right in rev. If I hold pressure on the prop it will skip still. Any suggestions? How can I be sure its the cable and not the unit?

Thanks,
Jeff

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

The mounting stud on the syncronization lever ia adjustable. As you move that stud closer to the mtg. stud for the upper cable, you can gain more reverse direction adjustment.

Are you refering to the stud that the shift cable attaches to? I have it adjusted about mid way. Like I said, I can have the cable in my hand pulling it out as hard as I can and it still skips when pressure is applied.

 

[RCAF_FB_FHDOG]

Re: Shifts forward fine, Grinds in reverse

Trim the unit up. From below, look up the leading edge to where the upper shfit shaft and intermediate shift shaft connect. Check their alignment and for any excessive play. If that looks good, pull the drive off and check the roller on the upper shft lever for wear at the shift cable fork. Then check the bushings in the bell housing for side play wear.

If nothing is found then, I would start considering something in the units set-up. I agree if you have the cable disconnected, pull out with some tension, and the dog will not engage, something strange is going on. The prop should definitely engage and lock when rotated clockwise.

I did have one of these give me fits until I discoverd the shift spool setting was out of speck. It can be too loose or too tight-both giving the same mal behavior.

 

[Don S]

Re: Shifts forward fine, Grinds in reverse

If I hold pressure on the prop it will skip still.

I think I now understand your problem. When in forward you turn the prop counter clock wise to see if it's in gear, and to hold it in gear when installing the drive. NOW, if you put it in reverse, you have to turn the prop clockwise for it to lock into gear. If you keep turning CCW, it will ratchet because you are going the opposite direction of the dog clutch.

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

Trim the unit up. From below, look up the leading edge to where the upper shfit shaft and intermediate shift shaft connect. Check their alignment and for any excessive play. If that looks good, pull the drive off and check the roller on the upper shft lever for wear at the shift cable fork. Then check the bushings in the bell housing for side play wear.

If nothing is found then, I would start considering something in the units set-up. I agree if you have the cable disconnected, pull out with some tension, and the dog will not engage, something strange is going on. The prop should definitely engage and lock when rotated clockwise.

I did have one of these give me fits until I discoverd the shift spool setting was out of speck. It can be too loose or too tight-both giving the same mal behavior.

I checked the shift fork and shift shaft for play today. It all appears to be in working order and traveling the correct amount, which also appeared to be equal movement in both dirrections. Forward made the shifter forward, neutral pointed it to the left, and reverse brought it almost 90 degrees from what it was in forward. Also I was noticing today that when the unit is in neutral I could hear something rattling from the lower with it in neutral. I guess I'll find out tomarrow when I take it back since I have tried all I know to do.

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

I think I now understand your problem. When in forward you turn the prop counter clock wise to see if it's in gear, and to hold it in gear when installing the drive. NOW, if you put it in reverse, you have to turn the prop clockwise for it to lock into gear. If you keep turning CCW, it will ratchet because you are going the opposite direction of the dog clutch.

Don, When it reverse it will rachet going CCW, but it will Lock, and then POP to the next tooth when turned CW. It should be a firm lock and hold just like it was in forward.

 

[Don S]

Re: Shifts forward fine, Grinds in reverse

Don, When it reverse it will rachet going CCW, but it will Lock, and then POP to the next tooth when turned CW.

That is NORMAL and how it should work.

It should be a firm lock and hold just like it was in forward.

Yes, it should lock firmly when turning CW. But it will ratchet when turned CCW.

Not exactly sure what you mean in the second sentence, really confusing

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

When its lshifted into reverse, I can rotate the prop both dirrections. One way it will ratchet, and the other it will lock, but POP with pressure applied skipping to the next tooth on the gear.

that make any sense?

Its like it is either not fully enguaging, or it is damaged. I can have the shift cable in my hand, pulling it out to its full extent and still turn the prop both ways in the manner discribed above. Just visually inspecting the shifter fork at the lower unit, it appears to be doing what its sapposed to be in both dirrections. This and the rattle lead me to beleave that this lower is internaly damaged but I am no certified boat tech so I guess we'll see what they tell me in the morning.:redface:

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

UPDATE: Took it to the shop and disassemble boat and could not find any issues with the boat, inspected the drive. Couldn't really determine what was wrong with it but we installed another drive and it works flawlessly. So the problem lies in the drive somewhere.

I'm back up and running untill the next issues appear!

 

[Don S]

Re: Shifts forward fine, Grinds in reverse

Did they dissassemble the drives lower unit? Did they inspect the shift spool per the OEM manual. How about the dogs on the clutch and reverse gear, are they all rounded over?

 

[RCAF_FB_FHDOG]

Re: Shifts forward fine, Grinds in reverse

The pinion height need to be checked as well as the shift spool adjustment. I had a brand new oem unit that was not set up correctly that did the same thing. It was weird as hell to put mildly. You would be surprised at what happens if the pinion height is aff by as little as .002" . I think there are some cases out there with a machining defect in them, but good luck getting Mercruiser to publish that. Maybe Mr Don knows about that. The one that wore me out was a 1623-5356a20 I-Drive.

 

[bigbroncoxlt]

Re: Shifts forward fine, Grinds in reverse

I'm not sure what was going on in that lower case. They claimed that it worked fine on the other boat, but I have my doubts. It would appear to shift fine out of water, but you load it and you would have quickly found the problem. Someone may have possibly been in that unit at some time previous due to the spanner nut at the input being loose, and the unexplainable shift issues. The world may never know!

Don, I expected them to disassemble that lower and find the problem but they just checked it on the stand. We dropped the lower first, then took the upper off. When I originally got the outdrive, The top seal was leaking. We found that the spanner nut was loose and tightened it up. When the drive came back off we found the seal was still leaking. They installed a new seal in the upper and pressure checked it. found a minor leak and repaired the leak, I'm guessing that somewhere between the lower not shifting and the input seal leaking he decided to just try another drive and so we didn't get into the lower. He may have after I left.

I'm just glad to be motoring again, to bad its going to be time to winterize soon! Thanks for all your input guys.