Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

[teddytedted]

:facepalm:

1978 140 HP Mercruiser
1978 Model 470 (pre-alpha) Mercruiser outdrive

After reading similar threads I'm fairly confident that we have "screwed the pooch", but here goes..

We just pulled the lower portion of the outdrive to replace the (shredded) impeller and failed to put it in forward gear. As much as I hate to admit this, when we paired the lower gear case with the upper we forced it a little - the last 1/4" or so was squeezed together by tightening the bolts a little at a time in a "star" pattern. It seemed to suck the lower unit in pretty easily, we didn't have to crank on the bolts very hard to get it together, but from what I've read it sounds like it should just basically seat itself into the upper housing, right?

After assembly we put the muffs on and it shifted into forward fine - reverse has been a little sketchy since before the impeller job but it did go in after a little bit of chatter. When I took it to the lake this weekend it started to chatter going into forward gear as well.

First question: we noticed water was coming out of the shift crank cavity around the shift shaft. Is this normal? Did we bend something or is there supposed to be some kind of seal in there?

 

[teddytedted]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

Here's a pic

 

[Don S]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

looks like the lower shift shaft is bent. You need to replace it, trying to straighten it will either break it or weaken it so it will break on a hot 3 day weekend.

 

[stonyloam]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

OK, you only need to have the control lever in forward gear if you are pulling the whole outdrive. Reason being that both the upper shift shaft coupler and the intermediate shaft must be facing straight forward, so the intermediate ss (in the outdrive) can slip back out of the upper ss coupler (in the bellhousing). You just dropped the lower, so the intermediate ss just dropped out of the upper, no problem. If they went back together OK, and the control handle moves freely back and your problem lies elsewhere.

 

[teddytedted]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

Thanks guys..

So is the "control handle" part of the picture above? From the manual I thought it was the shift crank and lower shift shaft. Also, it looks to me like there is a lip on the lower part that should just be seated on top of the hole (as if this whole assembly has been forced upward)? Is water supposed to be coming out of here?

The assembly pictured is loose - you can grab ahold of it and it wiggles around freely.

 

[stonyloam]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

The control handle is the lever up by the helm (steering wheel) that shifts the boat. If that connection is loose, (and it looks like it is) you may have left out the washer that goes on the lower shift shaft in the gearcase) and holds the intermediate ss up in contact with the upper ss.

 

[Bt Doctur]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

If the lower shoe was not correctly positioned on the splined shaft and you forced it to seat, you
may have bent the shift selector in the lower unit

.This willl greatly affect the engaugement of the lower gears where the shifting actually takes place. And no water should be squirting up from the shift shaft.

 

[cr2k]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

Take it apart and put it back together right. Only take 20 min. AND a new gasket.

 

[teddytedted]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

So we pulled the lower unit off and put it back together, everything seems to be okay it is going into forward gear now but it still chatters pretty bad going into reverse.

We pulled the whole outdrive today to replace the gimbal bearing and bellows and the picture kind of speaks for itself I guess. I'm not sure what the technical name is for this piece but it's chewed up pretty bad. 2 questions:

1. What would cause this?
2. Is it a problem, or will it cause more problems going forward?

Thanks guys!

EDIT: Sorry about the thumbnail/picture size.. I'm at work so I have to upload straight from my cell phone.:facepalm:

 

[dubs283]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

its bad if you found pieces of the retainer in the bellows

otherwise it looks like someone tried to remove it without the proper tool, either way its gonna be tough to get that off

as far as reverse chatter, you can try to adjust the shift cable, but in the end it probably just needs replacing

 

[teddytedted]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

nope sorry, I should've clarified: The exhaust bellows were cracked and needed to be replaced pretty badly so I ordered the whole kit and did all of the bellows and gimbal bearing while we were at it.

There was quite a bit of oil/grease that dumped out of the U-joint bellows when we pulled it off but no pieces of the retainer. Is there supposed to be a lot of gunk in there or is that a sign of bad bellows, seal , or something else?

 

[dubs283]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

if there is water and gear lube in the u-joint bellows, yes it is a sign of either a hole in the bellows or water entering from the bilge - more often than not its a hole in the bellows

the gear lube is from the drive puking it out from the water ruining the yoke seal and probably the yoke seal surface

time to drain gear lube and pressure test the drive

 

[teddytedted]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

Thanks Dubs.. pressure test it is.

Now back to the shifting problem.. I think we just has the lower shift shaft misaligned the first time.. it went back together a lot easier the second time and shifts into forward fine but there is a "clunk" noise when I throw it into forward.
Reverse is a different story and, like I said before, reverse has been a little sketchy since the end of last year. When I put it into reverse (pretty quickly) it "chatters" a little bit and by the time it shifts it's already into the throttle a little bit. We did notice some fine metal shavings in the gear oil when we drained it, so I'm afraid it might be the shift selector in the lower unit like in BT Doctur's pic above.

Any way to test it or should I just light the boat on fire and find a different hobby?

 

[dubs283]

Re: Shift shaft/crank issues after impeller replaced (forgot to put in forward gear)

like i said in a previous post, sounds like the shift cable may be out of adjustment or more likely needing to be replaced

if you try to adjust make sure you follow the PROPER adjustment procedure in an OEM (mercruiser) manual

the clunk you hear is normal, it is from a proper, brisk shift - the grind/ratchet is not, it is from an improper, slow shift or a mis-adjusted/worn out cable