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Pre Alpha - Adjusting the Shift Cable

T

tdf

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The manual says to move the control all the way forward and then spin the prop counter-clockwise until it stops.

My prop doesn't stop; it clicks as it continues to spin.

I have checked the "5 7/8 inch" lower cable distance from the barrel to the end hole in the cable (as specified).

Any ideas on what the problem might be?
 
Mercruiser made several drives in the "pre-alpha" window....telling us exactly what you have will yield a quality response from the get...
 
After reviewing other posts similar to my situation, the outdrive will engage the forward gear when the outdrive is trimmed UP.

I'm guessing that I have a stretched lower cable.

Is that a logical conclusion.....new lower shift cable needed?
 
who's manual are you using?

I'm seeing 6-1/4" in for the center-center distance on the remote cable, with it in full reverse...in the factory service manual...

If it used to work and you have had an overheat situation, then the remote cable likely received heat damage...
 
makomark said:
who's manual are you using?

I'm seeing 6-1/4" in for the center-center distance on the remote cable, with it in full reverse...in the factory service manual...

If it used to work and you have had an overheat situation, then the remote cable likely received heat damage...
Click to expand...
SELOC (Mercruiser) manual (Section 7, page 2)

Early Mercruiser (pre 1973) 5- 7/8 inches
 
5 7/8 is correct for early drives with the long slot in the reverse lock valve. I don't know the exact cutover but certainly early 70s.
Drive needs to be down, with lower cable disconnected from the lever, pushed gently in as someone rotates the prop until it locks.

NOTE: 5 7/8" is center of barrel to center of hole.
 
I've seen posts on this forum where the outdrive won't shift into forward gear when the unit is down, but will go into gear with the drive trimmed up
tdf said:
After reviewing other posts similar to my situation, the outdrive will engage the forward gear when the outdrive is trimmed UP.

I'm guessing that I have a stretched lower cable.

Is that a logical conclusion.....new lower shift cable needed?
Click to expand...
I have seen this condition in several other posts. But, none that I found go on to explain what was done to fix it.
Solutions like: 1) Adjusted the cables. 2) Had to replace the lower cable. 3) Replaced some other part involved in the shifting.

Solution hints anyone? (So far adjusting hasn't produced an improvement, but trimming the outdrive up makes it possible to get into forward gear)
 
The shift clutch slides freely fore & aft on the prop shaft for shifting. Since fwd gear is in the forward end of gearcase & rev gear is in the aft end, tilting the drive allows gravity to assist the clutch slide forward & assists it engage during your monkeying around.

This is why it must be adjusted with the drive down. Either you are not taking your time & pushing the slack in, not rotating the prop to verify full engagement, not measuring 5 7/8" correctly OR your lower cable is worn.
 
shift the control box in full fwd
push the shift cable plastic sleeve inward while turning the prop CCW till locked
attach cable adjust barrel to match the stud
shift into neutral ,prop should rotate freely
shift into rev, prop should lock cw , if not, raise the adjustable stud upward to get reverse lock
 
I appreciate every single reply to help me understanding what is going on. I'll try another attempt at adjusting, but I believe I'm in for a new shift cable.

One more question:
If a new cable is required. This drive being the early design where the cable threads in from the back side; Is it possible to replace the cable without removing the bell housing?
 
After more adjustment knowledge (thanks to Bt Doctur's reply) I have the drive engaging forward gear now. However, it will not engage reverse now. So maybe the cable did fail in tension.
 
Slide the anchor pin up the slot until reverse works. This will not affect fwd adjustment.

To answer your question about fwd entry old style cable. The bell housing will need to come off IF you use another fwd entry cable.

You can use a straight tap & tap the threads all the way thru from the front to rear & upgrade to rear entry new style cable. The tap is special so you don't ruin the theads. I'm not sure you can get the tap in & turned with the bell housing installed.
 
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a common issue with the older drives is the lower brass shoe or the splined shaft is worn beyond its limits and there is just enough play in them to make adjusting difficult. Both are easily tested and replaceable
 
I installed a new shift cable. I used the newer design. Much easier to install (run a tap to clear threads). I get forward gear no issue, but no matter how far run the anchor pin up the slot I still can't get reverse.
 
I think you are simply not pushing & pulling the slack out of the cables during the adjustment process. Easy to show & explain in person, not so easy in text.

Also, what brand of control do you have? I ran into a cheapo boat with a Morse Control with similar problems. Found that Morse had various mounting locations for the cable endsl studs because each engine brand had different travel ranges & Cheapo Boat Company used the incorrect holes. Boat never could have shifted correctly.
 
Droid said:
I think you are simply not pushing & pulling the slack out of the cables during the adjustment process. Easy to show & explain in person, not so easy in text.

Also, what brand of control do you have? I ran into a cheapo boat with a Morse Control with similar problems. Found that Morse had various mounting locations for the cable endsl studs because each engine brand had different travel ranges & Cheapo Boat Company used the incorrect holes. Boat never could have shifted correctly.
Click to expand...
My control box is the Bayliner original, as far as I know. I took it apart and cleaned/inspected. The cams that push the cables look good (no slop, serious wear marks or gouges). Lubed it before reassembly. Works smoothly now.

How do I access the possible Slack?
 
You need to push in or pull out on each cable as you make the adjustments.

For example, when getting the 5 7/8" on the lower cable since it pushes in, you must push in lightly when measuring & adjusting the barrel to achieve the dimension. And I should add, be sure the prop shaft is rotated CCW until it locks at the same time. This makes sure the clutch dogs are fully engaged. Best to have an assistant rotate & hold the prop.
With each subsequent adjustment, you must consider each cable travel as you push & pull respectively.

Another thing to consider is that if the cable was perfectly straight there would be zero slack but with each curve you induce slack as now the inner cable can move towards the outer radius of the bend while being pushed & towards the inner bend while being pulled. So consider your cable from remote control has a few zig zags plus 1 graceful 90 degree bend at the transom you will have slack. Old well used cables will wear & have more slack.
There may come a time when it's more than can be adjusted out & a new cable is due.
 
tdf said:
My control box is the Bayliner original, as far as I know. I took it apart and cleaned/inspected. The cams that push the cables look good (no slop, serious wear marks or gouges). Lubed it before reassembly. Works smoothly now.

How do I access the possible Slack?
Click to expand...
I don't know if Bayliner used MerControls or aftermarket. But after 56 years I'm going to assume it used to function OK.
 
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