boat stalls out

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
I own a 120 mercruiser engine with a 3.0 mercarb,engine starts no problem at all,but when started it's automaticaly in reverse,it won't shift out of reverse,it won't shift into foward nore nutrual,shifter does move though,if you try to change it into foward the engine will just cut out,same with reverse when trying to accelorate wi'll stuck in reverse,I recently pulled the "U" shaft drive from the bellhousing unit,
replaced the gasket where they connect,now could I have messed with something on the shift shaft and also could I have done something wrong while putting the "U"shaft back into place?I also rebuilt the carb,but I am very sure this is not the carb,ran the carb manualy and runs fine.
 
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Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: boat stalls out

You pulled the upper shift shaft to replace a "gasket" or do you mean seal?
If it worked before you did the work ,and now it dosent ,it would mean a need to double check your installation
 

mkast

Lieutenant Commander
Joined
Nov 6, 2002
Messages
1,934
Re: boat stalls out

Neutral safety switch adjustment.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: boat stalls out

Neutral safety is in the control box???????????
Do you mean shift interupter?
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

I replaced the gasket when checking the drive shaft for lubes,advised by a friend of mine.Never ran the boat before.my dads friend had no place to store it so I got a dollar boat thats turned into a couple.
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

so try a new shift interupter,or is there a way to trouble shoot it?it's stuck in reverse and if you idial up at all,in reverse or foward it dies.
 

danond

Lieutenant Junior Grade
Joined
Jun 11, 2007
Messages
1,118
Re: boat stalls out

Read the manual for your drive in the ADULTS ONLY post at the top of this forum. Worth it.

It sounds like you missed the shift linkage (I can't remember what Merc calls it) when you re-attached the drive to the pivot housing. It has to be in a certain position or shifting is screwed up like what you're describing.
 

hoot

Chief Petty Officer
Joined
Sep 8, 2002
Messages
434
Re: boat stalls out

i would pull the drive off again and reinstall, making sure the shift cable lever and shift shaft roller are connected. sometimes the lever will rotate a little and the roller will not be in the correct place. be sure the water inlet o-ring stays in place also...
 

180shabah

Rear Admiral
Joined
Mar 26, 2005
Messages
4,995
Re: boat stalls out

Shift linkage - ON the drive, is likely not properly aligned. Tilt the drive all the way up and take a look. Compare it to the picture in the manual.
 

erikgreen

Captain
Joined
Jan 8, 2007
Messages
3,105
Re: boat stalls out

Ditto. Almost certainly the shift linkage on the drive is in the wrong place with respect to the shift shaft in the bell housing. Sounds like you had the drive in reverse or neutral when you pulled it off, and it needs to be in forward gear when re-attached to align correctly.

Check to make sure you haven't bent it, that'll mess things up more.

Since you pulled the drive off, do you remember any rust on the shaft or U-joint? Was there a lot of dirt in there?

Really you should check alignment on the drive with an alignment bar, replace the lube inside the drive, and do all the other maintenance stuff listed inside the manuals in the adults only (dunno why it's named that) section.

Inboard/Outboard boats need lots and lots of maintenance... it's not hard to do, but it takes time, and you will need to spend money on gaskets, lube, a few tools, etc.

If you don't do the maintenance or the previous owner didn't, your drive can get goofed up fast and in need of expensive repairs. As expensive as doing the maintenance can be, it's much, much cheaper than the repairs.

No boat is free unless it's a rowboat in great shape. An I/O will still cost you a few hundred dollars a year in maintenance and fuel, assuming you do it yourself, even if you got it free.

Welcome to boating :)

Erik <--- I/O boat owner
 

180shabah

Rear Admiral
Joined
Mar 26, 2005
Messages
4,995
Re: boat stalls out

in the adults only (dunno why it's named that) section.
Caouse when it was named "click here first" - nobody did.

The hope was that people would be lured in by the sexy/naughty name and actually read the stickies like "how to ask a question" and then provide the information needed to get meaningful responses.
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

it's a 85 120 merc on a renken,new to it but clever and ilidorite
Ditto. Almost certainly the shift linkage on the drive is in the wrong place with respect to the shift shaft in the bell housing. Sounds like you had the drive in reverse or neutral when you pulled it off, and it needs to be in forward gear when re-attached to align correctly.

Check to make sure you haven't bent it, that'll mess things up more.

Since you pulled the drive off, do you remember any rust on the shaft or U-joint? Was there a lot of dirt in there?

Really you should check alignment on the drive with an alignment bar, replace the lube inside the drive, and do all the other maintenance stuff listed inside the manuals in the adults only (dunno why it's named that) section.

Inboard/Outboard boats need lots and lots of maintenance... it's not hard to do, but it takes time, and you will need to spend money on gaskets, lube, a few tools, etc.

If you don't do the maintenance or the previous owner didn't, your drive can get goofed up fast and in need of expensive repairs. As expensive as doing the maintenance can be, it's much, much cheaper than the repairs.

No boat is free unless it's a rowboat in great shape. An I/O will still cost you a few hundred dollars a year in maintenance and fuel, assuming you do it yourself, even if you got it free.

Welcome to boating :)

Erik <--- I/O boat owner
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

thanks guys the freakin shifter cable was all tweaked inside the top of the out drive,gotta order another,Thanks again for the help,and the carb runs like a champ,not bad for a first time rebiulder.:D
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

One more thing Now is the a kill switch that will kill the engine other than the key?Like a key that disconnects when the driver falls overboard?or is that a ciggaritte lighter holder?lol
 

180shabah

Rear Admiral
Joined
Mar 26, 2005
Messages
4,995
Re: boat stalls out

'85 probably doesn't have a kill switch, but they are cheap and easy to add.
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

I have to bypass my egnition by attching a wire fron the yel/pur wire nut to the positive nut on the started and then start it with a screw driver,you know the old starter trick,but the yellow/purple and the positive that I wired together send the spark to the coil,and if its not there the engine won't fire?whats the deal there?
 

Brian Drew

Cadet
Joined
Jun 15, 2009
Messages
14
Re: boat stalls out

When my interupter switch is pressed in I think it stalls my boat.It happens when shifting gears,how should I trouble shoot this?
 
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