Merc 120 I/O help

[Jdip83]

Hey guys.
I have a 1967 17ft Astro with a Mercruiser 120 I/O
First off this is my first boat.
The Boat has been out of the water since 1991 nor has it ran so now u know what I am up against

I the motor does turn over manually starter is being rebuilt.
Carb is off and I'm going to do a rebuilt this week.

I can not put unit into neutral or reverse with the control just feels frozen but I can move it all the way forward.
The steering is frozen to one side. it's frozen to starboard

So today I started to remove the upper part of the drive

I didn't remove the lower unit first.

I did remove the 6 locknuts and am trying to pull it off but it's not coming. Is it like pulling the drive shaft off a pick up out of a rear end? Or am I missing something?

I do have a manual but it's very vague in the drive unit section.

Also tent to remove the top Pic included 3 of the bolts came up but the third I am having trouble with.
Stripped it and so I don't know how to get it out. Any ideas.

Any help with the removal of the unit and or the top cap bolt

Thanks
Jon

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[Bt Doctur]

Re: Merc 120 I/O help

Now thats a project boat!!!!!!!!!!!!!!!1
shift must be in fwd to remove the drive. cut the shift cable at the boot and try to move the shoe in a straight line (bow to stern).If this cant be done, you will need to remove the lower half of the unit first, then the top half.Stubborn bolts can be removed with a hand impact driver.

 

[Jdip83]

The shifter does go into forward but I will cut the throttle cable and see if that works. Any idea about the steering
The wheel is locked too.

By the way
I'm weird like this I like to know why it helps me understand.

Why would I need to remove the lower unit first?

Why would I need to cut the throttle cable?

Sorry I'm that guy


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[fishrdan]

Re: Merc 120 I/O help

DON"T cut the throttle cable. BT suggested cutting the (lower) shift cable, at the drive, outside the boat.

For the locked steering, unbolt the steering cable from the drive's steering arm and see if this frees anything up. Several things could be bad, helm, steering cable, tilt tube, gimble ring. Start taking things apart until you isolate what's locked up.

 

[Jdip83]

Any pictures of what to cut.



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[Fishermark]

Re: Merc 120 I/O help

You need to do a little reading and researching before you continue simply taking things apart. For instance, why are you taking the top off of the outdrive?

At the top of the main Mercruiser forum here, there is a post called "For Adults Only." In there is a wealth of information for basic repairs, etc for your Mercruiser. You might be better off limiting your posts to one question at a time because with this project you will have many!

It sounds like a fun project, but make sure you know what you are doing before you cause more problems for yourself.

 

[ziggy]

Re: Merc 120 I/O help

yep, reading the oem service manual will be a real big help. you wanna read mercruiser, #1.

here's a pic of the shift shaft in the upper and the bell housing. the bell housing shift shaft is the female part of the coupler, the shift shaft in the upper is the male one.

in this pic. the helm is in neutral. the shift coupler has spun to port some. if it were in rev. it would be turned even further to port. when in fwd. the coupler faces fwd. they slide together. when in fwd. and the rams are free and the 6 nuts are removed, ya can slide the drive off aft. if not in fwd. it won't move because the shift shaft coupler won't slide apart.
if ya remove the lower. this allows the shift shaft in the upper to fall down and disengage from the shift shaft in the bell housing. then ya can remove the upper. to see the shift shafts like in the pic. tilt drive up some and lay on your back on the ground and look at the ft. of the drive.

 

[Leedanger]

Re: Merc 120 I/O help

Pretty certain you're gonna have to take the outdrive off, on a project like that it's one of the first things I would do. Put the drive in forward, if the remote throttle is toast you can try to do this manually by removing the shift cable off of the shift plate, you'll see the cable rising up from underneath the engine. If memory serves you would push the cable in if doing it by hand. Verify that it is in forward by moving the prop shaft (or prop if its still on) in the Counter Clockwise (CCW) direction...it should lock. If in forward CCW = lock and ratchet if CW. While verifying forward gear keep in mind that if you are doing it by hand meaning the shift cable is removed from the plate, you will have to continue to push it in while you turn the prop shaft or the test won't work. Now if that fails and you cannot move the shift cable either direction you may have to remove the two small square keeper screws on the end of the shift cable and remove the end exposing the wire so that when you pull the outdrive the shift shaft couple can be in the proper position. Reference the eloquent explanation by Ziggy above. You can't pull the outdrive without it being in forward gear or the coupler is in the way, I suppose you could just cut it but I'd say tread lightly sir until you know what you;re up against. It's not all that easy to replace when you're green.

Its very possible that even if you manage to get the drive in forward gear it will still seem near impossible to remove from the boat, they can be a bugger to get off if the engine alignment is incorrect and is smashing the drive shaft. When I was facing this issue, Bond-O recommended using the hydraulics to push the outdrive off. I had to actually carefully pull the engine first, out on an angle so the drive shaft could slip out finally without damaging it or the engine coupler.

As everyone else has stated you need to do some homework, everyone here is willing to help but if this is your first boat you got a hell of a learning curve ahead of you. Here download this: https://docs.google.com/open?id=0B4XV6tt7Q0P-OWEwYjgyZmEtNjI2ZS00NDEzLThmYTUtMTgyMmE0OGY2Y2Ux it's manual #1 which applies to you. Here is also the all engines 74-78 which may contain a few additional items you may need.

https://docs.google.com/open?id=0B1TAvwZ3TjhfOTI5OTMyZTMtNDNkZi00MDAyLWE5MTYtMTI5N2MyNDM3NjZm These are from google docs....it's safe.

 

[Jdip83]

Lee

Thank you so much for the PDF of the manuel
Boatinfo.coms is great but
The PDF is 1000x better

Thank you all for the advise will update you tmrw evening once I get the unit off.



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[Jdip83]

You need to do a little reading and researching before you continue simply taking things apart. For instance, why are you taking the top off of the outdrive?

It sounds like a fun project, but make sure you know what you are doing before you cause more problems for yourself.

Maybe I'm doing more than needs to be done but I want to go through the whole unit. One it helps me learn how it works and what everyone talks about so I know what pieces are and know what to call parts correctly. Plus if there isn't a problem with the unit than there shouldn't be an issue I learned what it is suppose to look like correctly rather than asking "is this suppose to be like that"

My big issue is when I went to drain the oil out of the unit there wasn't any
So maybe that's the way it is when it sits for 20yrs
Or maybe the guy I bought it from drained it.
Oh ya the guy I bought it from is he son of the owner which died in 93' so his knowledge was limited

I like projects
I'd buy a Chevy nova with a rod knock just to fix it and get it going
My big issue with cars and trucks are the about of rust they accumulate on the body
With boats u don't get that. it's Rot and I feel rotten wood is a lot Easier to work with plus cheaper than rusted frame and body

But the motor is always first
But for me on this boat it's a whole new thing to learn rather than buy fix drive and sell Cars and trucks
I could buy 5 boats fix them and use them all for the prices I've spent on fixing up cars in the past 8 yrs
Not that I'm going to buy 5 boats just saying for the money I've put into all the cars I could boats too.

And I'm only 28 ya I know a kid compared to a lot of you old sea dogs not being mean just a joke and am very grateful for everyone's help
Sorry for the extra info but wanted everyone to know what I was about

Thanks again


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[stonyloam]

Re: Merc 120 I/O help

There are only a couple of things that are holding the outdrive from coming off. If the shift shaft in Ziggy's photo is not pointed straight ahead, the linkage will not slide apart. The second, that can be more problematic is that the splined driveshaft is stuck in the coupler. If it seems to come out a little then pulls back, that is probably it. Look behind the engine and you will see the shaft going into the coupler. The coupler is rubber with a female splined coupler molded in, so it might give a little, but be stuck metal to metal. Should have grease on the shaft, but after 20 years could be pretty rusty. good luck.

 

[Fishermark]

Re: Merc 120 I/O help

Maybe I'm doing more than needs to be done but I want to go through the whole unit. One it helps me learn how it works

I understand the desire to know how things work.... but sometimes simply taking something apart to discover how it works can cause damage if you do not know what you are doing. With an outdrive there are gears involved and shims and tolerances and... well, you get the picture. If you take the wrong part off and do not put it back together right, then it will not last longer than your first voyage.

I am simply suggesting you get some basic knowledge of what to expect before you start your disassembling process. I too am a "gear head" and enjoy working on cars and engines and "stuff." Enjoy the the restoration! And be prepared for many challenges ahead!

 

[Jdip83]

Success
FINALLY got the Drive off today
I know what I am going to invest in Tomorrow Anti-Seize and lots of it.
You will see why.

I am sure glad I pulled it off before I started The motor.

After seeing what I have seen today I am going to pull the motor and either go all the way to the crank or maybe pull the pan off and go from there.
That's the stuff I know
Now to the part of mystery. I am defiantly going to do a lot of research and talk to a few mechanics locally and ask lots of questions as I go with the drive.

Thank you to everyone with your help getting it off
By the way I didn't have to cut anything
It was a lot of corrosion and electrolysis
Primally electrolysis

Thanks again
Any ideas on where to go next

 

[Don S]

Re: Merc 120 I/O help

In the marine industry, we call that big $$$$$$$$$$$$ to fix. Lots of parts and lots of time in labor.

Pull the bellows off the gimbal housing and I would bet money the gimbal housing is shot (corroded away).

 

[Jdip83]

The good part I got a gimbal housing from the guy I bought the boat from no charge at-least
So we will see.

 

[Pmccraney]

Re: Merc 120 I/O help

The second, that can be more problematic is that the splined driveshaft is stuck in the coupler. If it seems to come out a little then pulls back, that is probably it. Look behind the engine and you will see the shaft going into the coupler. The coupler is rubber with a female splined coupler molded in, so it might give a little, but be stuck metal to metal. Should have grease on the shaft, but after 20 years could be pretty rusty. good luck.

This was going to my guess... Because i had the unfortunate experience of my yoke actually rusting to the gimbal bearing (which came out with the drive after a tug of war -not good/normal)..because of water sitting in the bellows and rusting the whole u-joint assembly. Not my neglect (the p.o.s). A new u-joint assembly can be fairly pricey....if you find that the issues arevwidespread, you may want to consider buying a donor boat with a working (not corroded) drive line with all matching assemblies as opposed to rebuilding piecemeal, as don s. noted above.

 

[Jdip83]

Re: Merc 120 I/O help

This was going to my guess... Because i had the unfortunate experience of my yoke actually rusting to the gimbal bearing (which came out with the drive after a tug of war -not good/normal)..because of water sitting in the bellows and rusting the whole u-joint assembly. Not my neglect (the p.o.s). A new u-joint assembly can be fairly pricey....if you find that the issues arevwidespread, you may want to consider buying a donor boat with a working (not corroded) drive line with all matching assemblies as opposed to rebuilding piecemeal, as don s. noted above.

The shaft wasn't what was hanging it up
it was the housing on the drive unit on my other post with the pics its the top picture.
The shaft was greased nicely.

 

[Jdip83]

Re: Merc 120 I/O help

In the marine industry, we call that big $$$$$$$$$$$$ to fix. Lots of parts and lots of time in labor.

Pull the bellows off the gimbal housing and I would bet money the gimbal housing is shot (corroded away).

So a little update

I bought a different boat.
So I put the boat up for sale and didn't get any hits. So I decided to scrap/ trash it. I removed all the cleats and aluminum pieces I could sell or scrap.
While pulling the motor The front engine mount basically pulled right out of the rotten floor. The whole transom mount for the drive unit was corroded on the bottom. The transom was rotten at the very bottom. I drilled the transom in a bunch of spots but all were fine It was only around by the bilge area. I have made a bunch of mistakes on this boat.
So I hope I did it right with the this new boat.

 

[Bondo]

Re: Merc 120 I/O help

I bought a different boat.

Ayuh,.... Probably a Wise decision,....



Good Luck with the New barge,....
What's it got for a motor/ drive,..??