Positioning and function of a Mercontrol

[Rekdivr]

Good Morning,

This is my first post, and my first boat. I recently picked up a:

1967 Penn Yan 18' Stern Drive
Mercruiser 120 Engine, inline GM 4cyl 153ci
Engine Serial # 2053740
Model 120 Stern Drive

The boat has been sitting in a garage for 8-10 years.

After tuning it up so the engine is running properly, I notice the Throttle and gear control seems "sloppy". Since this is my first boat, i am curious how this Mercontrol is supposed to work. The Mercontrol is a single lever, dual function sidemounted unit. I have the Clymer shop manual for this engine, and I think adjusting the cables will be pretty straighforward, but I am wondering how it is supposed to function. For example, when i shift forward, when does it shift gear, and when does it give throttle? And what position should it be in, andf how many gears does it have?

Also, does a rebuild kit exist?

Here is a picture of it, this picture is actually one i borrowed from another post on this site. But it is the exact controller i have.

Thank you in advance for your time.

 

[ziggy]

Re: Positioning and function of a Mercontrol

i've got the same mercontrol as ya have.

I notice the Throttle and gear control seems "sloppy

mines loose feeling too. might be the nature of the beast depending on how sloppy/loose it is. mine being loose still functions proper.

i am curious how this Mercontrol is supposed to work.

neu. is as in your pic. push the lever fwd to engage fwd gear, further forward to advance throttle. same for rev. but pull the handle aft instead of fwd. the little black button in the center of the words mercontrol is to allow you to disengage the shifting so you can advance the throttle w/o shift. push the button in (yours already looks pushed in, in your pic), then with the button pushed in, move the lever fwd to adv. throttle only.

I have the Clymer shop manual for this engine, and I think adjusting the cables will be pretty straighforward, but I am wondering how it is supposed to function.

to bad ya got a clymer manual. go get s/m #1 from (click) here. or ya can get the book from mercruiser, or try ebay. i got both my s/m's (#1 & #2) used from ebay. about the only thing i've got from ebay. like that was relevant,. as for how to adj. the cables. it isn't straight fwd. you need to get the mercruiser s/m and read the adj. procedure. follow it sentence by sentence. comply with ea. sentence.

when i shift forward, when does it shift gear, and when does it give throttle? And what position should it be in, andf how many gears does it have?

on the two mercontrols i've had, starting in the neu. condition. move the lever fwd. you'll feel a detent as the lever comes from neu to heading towards fwd. however the shift hasn't occurred yet, move it further fwd and it'll shift. make the shift snappy. there are undercut gears trying to engage, ya don't want a ratcheting sound, this would be the gears shaving ea. other off but not engaging. opposite is true for rev. also. so shift snappy. have your idle speed set to spec. lower the better. high idle damages drives. as for how many gears it has, 2, 3 if ya consider neutral. it's either in fwd, neu. or rev.
don't know if there's a rebuild kit. try here and follow to your system.

 

[Rekdivr]

Re: Positioning and function of a Mercontrol

Hi Ziggy,

your information was perfect, thank you so very much. I was able to feel everything you described, the gear location and the throttle. The mercontrol seems to be operating correctly, albeit with that little slop, but it shifts and throttles as you described.

While working it last night, and based on your response, i have two new questions.

1- When i shift into reverse, and then further throttle it in reverse, the engine shuts off. It seems to me that there is actually a cut off switch located in the transom, which shuts down the engine when it is throttled in reverse gear. That makes some safety sense. My question is, two-fold, A) is that supposed to happen and B) how quickly should it shut off. It will only allow me to be at idle speed in reverse, the second i try to throttle up, it begins to shut down. This does not happen in forward, engine runs good in forward all the way up to 4,000 RPM.

2. The ratcheting sound you mention when shifting, i know exactly what you mean, i heard it because i was shifting slow. Question is, when i shift snappy, will i hear any "metal on metal" , like the gears engaging, or should it be silent with no sound.

I have been working on this boat for two months now, and am finally ready to put it in the water tomorrow for some sea trials (back bay to be specific).

Thanks again for all your help, your post was the perfect information i needed to make sure the mercontrol was working properly, or not.

 

[ziggy]

Re: Positioning and function of a Mercontrol

1- When i shift into reverse, and then further throttle it in reverse, the engine shuts off. It seems to me that there is actually a cut off switch located in the transom, which shuts down the engine when it is throttled in reverse gear. That makes some safety sense. My question is, two-fold, A) is that supposed to happen)

assuming it's a 67 ya should have the mc-1 drive, same as mine, different gear ratio probably. good thing it's not a 66, that would have been a 1B EZ drive. not many of them discussed about around here. anyways. it shouldn't do that.

B) how quickly should it shut off.

it shouldn't.

It will only allow me to be at idle speed in reverse, the second i try to throttle up, it begins to shut down.

have you replaced the shift cable recently. if not, this to me sounds like the start of a failed shift cable. cutting out and dieing when your shifting from r or f back to n or throttling up.

that's a pic of what i think ya likely have for a shift interrupt set up. ya can see the lever of the switch in the upper right corner. the roller of the lever sits in a v shaped block with a big spring on it. the v shaped block moves when shifting from r or f back to n, tripping the switch and cutting off the engine for just a split second allowing you to shift the undercut gears back to neu. read this.

Question is, when i shift snappy, will i hear any "metal on metal" , like the gears engaging, or should it be silent with no sound.

when i shift, depending on how snappy i am, i'll either hear or feel gear teeth ratcheting for one or two teeth. then thunk into gear. if i do the shift better all i hear and feel is clunk into gear be it f or r.

I have been working on this boat for two months now, and am finally ready to put it in the water tomorrow for some sea trials (back bay to be specific).

have a great time with your sea trial. hope all goes real well for you. i'm hoping to get out today too. 71* lite east winds w/ low humidity.. it should be a great day i hope.

 

[Fishermark]

Re: Positioning and function of a Mercontrol

You're right about there being a cut off switch - but not about its purpose. Look at the stickeys on the top of the page under the "adults only section. There is a post there about the function of the "shift interrupt switch." If your engine is dying when you advance the throttle in reverse, your lower shift cable either needs to be adjusted, or the shift cable replaced. (My money would be on the need for replacement.

When you shift you will hear a definite "clunk" going into gear. That is perfectly normal. You want a clunk, not a grinding. Make sure your idle speed is set correctly as well.

Good luck!


EDIT: Looks like Ziggy beat me to it!

 

[Rekdivr]

Re: Positioning and function of a Mercontrol

Ziggy, Fishermark,

Thanks for all the advice, here is what we learned on sea trials:

1. shifter cable is definitely in need of adjustment or replacement, as we stalled out many many times while in the water, and only during shifting gears, and it was not limited to reverse.
2. I am taking on water somewhere.
3. the bilge pump was not working, which led to an entertaining manual bilge by myself and father in law.:facepalm:
4. Low tide for a rookie captain is not the best time to take an unproven vessel ( and unproven captain) into the water, as i ran her slightly aground and my first mate (father in law) had to push us off. :redface: ( it wasnt low tide when i started, but it definitely was by the time our trials were over
5. Rear tilt for stern drive, while working on land, did not function correctly in the water.

So we are back to the shipyard for some more work.

Here is the good news,

1. I launched with relative ease
2. we made several trips around the bay
3. The entire family got a short ride
4. We did not sink, although without manual bilging from myself and father in law, that could have turned out differently.
5. we returned safely to the dock
6. we loaded the boat onto the trailer.

All in all a succesful day, but back to the shipyard (driveway) for more work. I will probably need a little more guidance on the shifter cable, but i have ordered the service manuals like Ziggy mentioned, it will be several weeks before we can get parts and back in the water.

Thanks for all your guidance, hopefully when i get into the shifter change project, you guys might be around to guide me on some questions if i have them.

Ziggy, hope you had a nice day on the water.

Although we didnt have a flawless day, we did enjoy ourselves!

 

[Fishermark]

Re: Positioning and function of a Mercontrol

5. we returned safely to the dock

That's always good news!

First thing I would suggest doing is finding the source of the water intrusion. First suggestion would be to remove the outdrive. Look and see if there is any water in the bellows. It is also a good time to inspect everything in there - gimbal bearing, drive bellows, etc. If it were my boat, I would simply replace all of the rubber parts without even wondering if they were good. The drive and shift bellows, shift cable and water hose. If there is water in the bellows area, then go ahead and replace the gimbal bearing as well. If no water is present, then simply see how the bearing turns by hand. Nice and smooth? Probably okay.

Good luck - you have some reading and work to do! Be sure to read through the sticky posts at the top of the page with good Mercruiser info.