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1972 mercruiser 140 dies when I put it in gear and won't engage, help!

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2101394sam

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So I have a 1972 Mercruiser 140hp stern-drive. I'm 19 years old and having a hard time with this boat. I rebuilt the 2 barrel Rochester carb and replaced all the good stuff on the engine and tuned it to specs.. now she runs like a top.. I go to shift it into gear and it just dies. suddenly no life! it does the same thing in either forward or reverse. the shifter lever is separate from the throttle, and it is really hard to push all the way forward or backward. there are 2 cables coming from the back and they look pretty old/rusty. and i suspect that the cable needs to be adjusted or replaced. I'm broke as hell so I'm hoping to get it adjusted and lubed up. anybody know how to adjust the cable? here's some more info, I read about an interrupter switch that kills the engine to relieve pressure on the gears so engage and disengage. it seems like the cable is so loose that it is only shifting like half way and getting stuck in the shift interrupter range.. so to speak lol... anyway, I have tried to put it fully into forward and turn the prop. and it spins freely, same with reverse. but once i really crammed the bastard into forward as hard as i could and when i turned it the prop made a clicking noise like the gears were just barely touching but not able to engage. and that's about all i got.. the hull is a Schuster tropicana 17ft. the engine runs really good, and I'm hoping I can pull a tube, wakeboard or a knee board with it. what do you guys think? any info will be greatly appreciated. I am a novice with boats and would really appreciate any help.
 
Welcome aboard ! The lower cable might be bad. The cable that goes to the throttle might be bad.

Directions for a Throttle and Shift Cable Oiler

You need a foot and a half of 3/8 ID reinforced plastic hose from Lowes, a tire valve, three hose clamps, a tire pump or small 12 volt air compressor with a gauge, and some MMO (Marvel Mystery Oil) or other light oil.

Shave the tire valve down and clamp it in one end of the hose.

1. Remove the fittings from one end of the cable.

2. Put 3 inches of Marvel Mystery Oil in the hose for every 20 feet of cable length.

3. Double clamp oil filled hose over cable.

4. Apply and maintain 50 PSI of air to the tire chuck. DO NOT EXCEED 50 PSI.

5. It will take 10 to 30 minutes for oil to appear at the other end, then your done. Have rags to catch the oil if your in a sensitive area.
 
That is a genious idea! I wish I had learned of that before. Anyway, There are two seperate levers. one for throttle and the other for shifting into forward and reverse. I can rev the engine easily. But it's the Gear shifter lever that is really resistant going back and fourth. how do I remove the lower cable? And how can I put it back on/adjust it properly? And when it's off, can I try to manually shift it? If so, how do I do that? What do I push or pull? And what should it do once it's in gear? Should the engine be running?
 
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So I pulled the lower cable and it's hard as a rock. I can't push or pull it at all. the shift lever up front moved easily now that it is detached so it is the lower one for sure. I have read alot of the online manuals. am i going to have to pull the stern drive off to remove this cable!? I am not looking forward to this lol.
 
2101394sam said:
So I pulled the lower cable and it's hard as a rock. I can't push or pull it at all. the shift lever up front moved easily now that it is detached so it is the lower one for sure. I have read alot of the online manuals. am i going to have to pull the stern drive off to remove this cable!? I am not looking forward to this lol.
Click to expand...

Ayuh,... The drive comes off, then the gimbel housing is removed....

I'd replace ALL of the rubber parts while you got it apart,... as well as the cable...
 
Okay, I guess I should do it anyway. There are 3 rubber boots that I see down there, one very large one, a medium one, and then the one I assume that is for the shift cable. All of them have cracks forming and look pretty old. Will some parts be exposed in this process that I can lube? Like joints or gears that need thick grease? Thank you guys again for all the help.
 
also, the gimbel housing, can i just pull the part in the back off to get the cable out? I'm not going to have to remove the engine or anything right? pulling the drive seems simple enough, just the trim rams and the six bolts and she slides out. but I'm not so sure about the gimbel housing.
 
Ayuh,... Like I said at the other site we're chattin' at,... Look in the Manual, 'n follow it Exactly....

It'll go Best that way...
 
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