Stuck in forward gear

[Fodder]

I am afraid my newly rebuilt engine is pooched, to put it technically. I was maneuvering in the marina on the weekend in a tight spot and was shifting back and forth from forward to reverse. Suddenly, I heard a 'thunk' and the engine stopped instantly. I was drifting towards a much nicer boat than mine so restarted the engine. As soon as I tried to put it into reverse, the engine stopped again. Uh-oh.

I limped to a nearby dock and tied up and went below to see what I could. So, here are the symptoms and steps I've tried:

1. The engine will start in forward gear
2. The prop shaft would not turn in neutral or reverse at all. I have a hand-crank and cannot move it.
3. I removed the cover plate and took the pictures below before trying anything.
4. I followed the procedures for adjusting the forward gear and loosened the tension by a couple of tines.
5. The prop shaft will now enter reverse for about a quarter turn of the hand crank before seizing up again.
6. At any time I can put into forward and freely turn the engine using the hand-crank.
7. There is no grinding sound or grating of gears that I can detect.
8. The prevailing wisdom of my marina buddies is that there is something wrong with the planetary gears. That sounds like I know what I'm talking about, but I really don't.

Does anyone have any thoughts about what I might try next? I am going to pull the engine again this weekend so that I can more easily access the transmission. The engine itself was running beautifully after having been rebuilt this winter. I shudder to think what this will cost to repair.

Thank you for any suggestions in advance.

[Dave Neptune]

Take a look

Fodder, you may be able to see the planetary assembly with a mirror. If you can wiggle the drum and see if the planetary gears are moving. Any rotational movement is fine however if they move laterally or "off axis" that's bad.

Before anyone else asks did you look under the boat to check the prop for fouling?

Dave Neptune

[Mo]

Fodder,

Check what Dave said first.

Are you sure your reversing gear was set up properly after the rebuild. Something is going through my tiny little mind...trying to get my head around this...

I wonder if the clutch plates were slipping and got hot. ??? could they fuse together and lock in forward," Probably wouldn't notice until it was run good in forward gear and then won't come out.

I'd give MMI a call and see if they have ever heard of anything like that. I've done a search and could not come up with anything.


EDIT: On second thought.
- is the shift handle moving? Is the cone moving inside with movement of the handle.
- are all pins and shafts in place that you can see. There is one shaft that goes straight across the reversing gear body that the shift handle is on.
- fluid/oil level checked?
- start it up in forward and look to see if the shaft is actually spinning...if it is you have a shaft connection.

[yeahjohn]

When the engine is not on can you shift in and out of forward and reverse? Is the operation cone traveling up and down the tail shaft and going into forward? So the engine will run in forward all day long? When you go to put the engine into neutral it stalls?

Maybe just maybe the reversing gear band is to tight? When your engine is not at significant rpms it stalls the engine . While running at hire rpms it can move regardless of the over tensioned gear band. You mentioned you adjusted the forward gear assembly but not the reversing gear band. Sense you cant spin shaft by hand it makes me think the reversing gear band is to tight, you have a fouled prop, or prop shaft is rubbing the shaft log?

-If the tail shaft is spinning you are linked to the engine.
-If you can shift the operation cone into and out of forward you are good there
-The reversing gear band simply clamps down on the gear assembly to switch rotation, I would think if that was to tight it would only cause stalling in forward but who knows

Regardless you can get a nice gear assembly for a good price rather easy, and then the work is just on your time. Not the end of the world.

[edwardc]

• Since you can run in fwd, the prop is not fouled.
• Since the shaft doesn't turn when in neutral, fwd is still engaged.

To me, this suggests that something has gone wrong in the fwd clutch assembly, preventing you from coming out fwd while trying to engage reverse. This has the effect of putting the reverse band clamping on a driven drum and stalling the engine.

Since your operating cone seems to be positioned in neutral (at least it's out of the fwd detent), it would seem that the problem is not associated with the cone.

Perhaps the noise you heard was one of the fwd clutch disc plates breaking and becoming wedged, effectively keeping the clutch engeged at all times.

I suppose if one of the planetary gears broke or became otherwise jammed, it might produce the same effect as an engaged clutch, trying to spin the whole assembly as a single unit.

[Fodder]

Thanks for the thoughts and suggestions on what to try. I'm heading back up to the boat on Friday to check off the list of items to review. I'm going to pull the engine out again (sigh) to make it easier to get to the transmission. Luckily we have a very handy ginpole at our marina and the Islander 32 is pretty accessible.

My checklist:

1. With a mirror, wiggle the planetary assembly and see that the gears are moving (since the shaft turns in forward, I'm going to assume this will be 'yes').

2. Check for fouled prop. - Seems obvious but I can't say that I actually checked even though it turns in forward gear. I'll check.

3. Check for fused gears- There is a definite possibility that things got hot in there. The boat has the hot water by-pass modification which means I've been working on balancing the running temp which now sits between 160 and 180.

4. Check for shift handle movement - I removed the Morse cable from the shift handle and can move through the range of gears. Starting in forward works fine and the propellor shaft does turn.

5. Check for stall conditions - Yeahjohn, yes it will run all day in forward but as soon as I try to shift to neutral or reverse, it stalls out.

6. Follow-up from #5 - Check reversing gear band for excessive compression. I'm sure we checked this but now I'm double-guessing myself.

7. Check forward clutch gear disc plates and planetary gear teeth for jamming.

Looks like it's going to be a busy weekend. I'll follow-up with a status update when I've been able to dig deeper. Thank you again for the advice and counselling.

[Mo]

Pull engine..not yet.

Don't pull the engine right away until we sort out the easy stuff. This might be a fairly easy fix and if not then you can pull. Your engine temp would not affect the performance at 160-180. "If" your forward gear was not set up right there might have been slippage that generated excessive heat right there in the box and sort of "crystallized" them...that's just an idea...not fact. Take your time testing with someone shifting manually without the morse cable and see what you come up with. Try and go through the adjustment procedure and see what you come up with.

With the shift handle in forward the shaft shouldn't move; in neutral it should move by hand, in reverse it should bind up. Check the adjustment on everything. If the reversing band was indeed too tight it could also heat up (maybe even start to disintegrate)...need to have a good look at it all....

Read through the reversing gear material and have a good understanding of it before you check on the weekend. This might not be too bad.

[yeahjohn]

I agree with what Mo said. Take a deep breath and look over everything.

[brewgyver]

(snipped)
Looks like it's going to be a busy weekend. I'll follow-up with a status update when I've been able to dig deeper. Thank you again for the advice and counselling.

so, where's that update?

[sailaboatjunkie04]

I am interested in what you found.

Hi, If you can answer on the forum it would be helpful...I have a engine that is stuck in forward...and I can not get it out, Please help.

[Easy Rider]

What about disconnecting the shaft from the engine and see if the shaft and prop spin freely freely. That might at least eliminate the fouled prop theory.

Chuck

[sailaboatjunkie04]

My fix for stuck in forward

Hi, After talking with Don at the help desk, and taking apart the pieces of the tranny...I took the video course and realized I was going the hard way.
1) Took on line video from Moyer Marine
2) I put everything back to where it was supposed to be
3) Called Don and he said to put vice grips on other side of shift shaft and give it a yank out of forward..It popped right out...OMG. I just wasted 10 hours taking unnecessary things apart...
4) Adjusted in slip the forward then reverse..and that took a process after the 7 time adjusting the tranny, I launched out..still had a issue in open water I tuned the tranny in and the it is operating perfectly now...

My biggest suggestion..Take the online course from Moyer Marine...
Thank you Don and this forum for the knowledge and support!

[Vermonstah]

Well done!

Junkie,

Quite the accomplishment already.

I have never so much as even removed the tranny cover on my A4. Thanks for sharing your insights and lessons learned.

+1 for Don and MMI

[roadnsky]

...My biggest suggestion..Take the online course from Moyer Marine...
Thank you Don and this forum for the knowledge and support!

+1
This should be suggested in the NEWBIE Section too.