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Throttle cable linkage

justin339

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"i have a 1979 mercruiser 140

"i have a 1979 mercruiser 140 hp with a alpha one, and i dont know how to properly adjust and connect the cables. when we took it out we only had reverse..
PLEASE HELP!!!"
 
"I have never read the "ma

"I have never read the "manual" but I can tell you how I go about this.
First, did you only have reverse -- that is not even neutral? Did it shift into reverse and out only to neutral? At different times, I have had both upper and lower shift cable problems.

If there is no shift action at all, it could be a loose connection or a broken cable. Check cables first. Does moving the shift lever actually move the shift mechanism in the engine compartment? If not the upper shift cable is loose or broken.
If the upper cable is intact, disconnect the lower shift cable from the mechanism in the engine compartment. Manually move the lower cable fore and aft to determine if anything is happening at the drive unit. A helper is handy to slowly turn the propeller as you move this cable. It should engage at each end of travel, with a neutral obtained between these positions.

If you can detect all three gear positions and cables seem to be intact, put shift lever in neutral position, manipulate the cable back and forth until confident you are in neutral, spin the adjuster in the engine compartment until the mount is aligned with its keeper and lock it down again. Hook up flush water and try it with engine running.

If you cannot detect forward, neutral, and reverse gear engagement, the lower shift cable could be disconnected at either end, or broken and require replacement. Or the shift slide bar could somehow be broken or disengaged. If cable is broken you may find it pulling out into your hand. At this point you are probably going to have to pull the lower unit to replace the lower shift cable, or reconnect something. Worst case scenario is that the mechanical shift mechanism is broken or a gear stripped.

Someone may have a printable reference."
 
"IT CHANGED FROM NEUTRAL TO RE

"IT CHANGED FROM NEUTRAL TO REVERSE AND BACK INTO REVERSE, BUT I JUST DISCONNECTED THE LOWER SHIFT CABLE, AND THE PROP DOES NOT ENGAGE OR ANYTHING IN THE THREE DIFFERENT POSITIONS. I DONT KNOW EXACTLY HOW THAT IS SUPPOSED TO WORK BUT I WOULD THINK THAT THE PROP WOULD ONLY ROTATE THE ONE WAY DEPENDING ON WHICH POSITION THE CABLE IS PLACED IN."
 
Is this boat still in the wate

Is this boat still in the water or out such as on a trailer?Were the drives pulled since last run?If so...was the shifter put in the forward position for instalation?I would make sure your shift arm is not bent...Todd
 
"the boat is on the trailer. i

"the boat is on the trailer. i changed the water impellor before the last run and i did have it in forward when i took the lower stern drive off, how do i check to see if the shift arm is bent?"
 
"If your drive went back on ea

"If your drive went back on easily then you are ok...If you used the 6 bolts to draw the drive in to the gasket,which would mean the shifter was not totally in forward and this would bend the shift arm.I know...did it myself once.
Lay down under the drive and look up from the bottom with a flashlight.On the drive side you should see that the tongue of the shift arm, so to speak,went into the slotted piece on the boat.Have someone shift slowly while you watch and see what is moving.Best I describe it basicly and then we can go from there...Todd"
 
"the shift arm is stationary o

"the shift arm is stationary on one side, i moved the shift cable as well as the prop in between movements and the shifter arm did not move, it looked like it was trying to move but didnt, and also when i rotate the prop there is a knocking sound"
 
"OK...now we are getting somew

"OK...now we are getting somewhere with more info.The clicking sound is the fact that you are not totally in a gear and will stop making a noise when you are in positve gear we will say.Do not worry about that yet.Will get to that later.So what you are telling me is that your shifter is able to go from complete forward position to neutral to complete reverse.And you are also telling me that the little shift arm is in the slotted item we wrote about before.So that I understand you correctly....when you shift....neither of thes pieces turn, but a little bit like its trying.....or does one side pull out of the other leaving the one still?Are we on the same page so far?...Todd"
 
"yea, thats pretty much it, as

"yea, thats pretty much it, assuming that for say when in reverse the piece would be pointed to the left and when in forward it would be pointed to the right..not sure on direction wise but thats how it changes gears right?"
 
"Yes that is how it changes di

"Yes that is how it changes direction.You did not answer the one question though.When shifting...do both parts turn together and then go the other way together?If they do then proceed,...when kneeling at the back of the boat...have someone go to forward position and try turning the prop counter clockwise...it should not......also...have them shift to reverse and try turning clockwise....it should not...Todd"
 
when shifting neither of the p

when shifting neither of the parts turn. it stays still..i also turned the prop when shifing and nothing happened...it is called the lower shift shaft that were talking about right?
 
"Justin,
That is correct.


"Justin,
That is correct.At this point I must then ask if you ever changed any of the settings of the cables up near the carb?If not proceed.What I would do at this point is remove the drive from the boat and see which is working and which side is not.Did you ever take a drive off before?If so....after removing, stand the drive up and see if the shift shaft turns and if so the prop(or the shaft the prop is on)will lock as we wrote about above.I will bet on the cable as your problem,but first try shifting the boat and see if the shifter is able to make the cable move freely.....Todd"
 
"i took the lower stern off on

"i took the lower stern off once before and im thinking thats how the problem started..i have the cable disconnected from from up above by the carb, so what i have been moving to test it out is the cable directly out of the drive itself. which way is forward, the cable at the longer length or the shorter length(extended or contracted)"
 
Got me there...Not 100 percent

Got me there...Not 100 percent sure which way the cable must go to do which direction....So the answer is yes that you have changed some of the settings by the carb and the barrel lock position on the cables.Is this true and you are also saying that you can not pull the cable that goes from the carb to the drive as it will not move...Then the drive must come off as said above....Todd
 
"i have changed settings, yes,

"i have changed settings, yes, but the cable does move in and out, when the shaft does not move at all, so does this mean that the shaft is broken or?"
 
"If you have the lower cable w

"If you have the lower cable with the carb end off and the cable moves, but does not turn the shift shaft....then its time to pull the drive....Todd"
 
"I have the opposite problem:

"I have the opposite problem: 1979 Mercruiser 470, 170 hp in a Bayliner; Throttle cable broke; installed a new one, connected to the carb exactly like the old one only now I have fwd and neutral but no reverse. Any suggestions? Thanks. JW in Dixie"
 
"justin;

Not sure if this w


"justin;

Not sure if this will help, but the lower shift cable where it attaches to the shift interrupt switch bracket; moves stern to engage forward (go figure) and forward to engage reverse.

Meanwhile the lower shift shaft turns CW to straight ahead in forward, and CCW to about 9 o'clock (viewed from above) to engage reverse.
Hope that makes some sense.

If you are moving the lower shift cable from stern and forward, and the lower shift shaft is not moving, this could mean the cable is separated (not likely), or the upper shift shaft swivel arm roller is not engaged with the slider. The upper shift shaft could be sheared, but this is not likely either.

If you had the drive off I am betting you did not quite get the arm on the upper shift shaft properly engaged with the shift slider. Very easy to mess this up. Just needs to be refitted.

In any case your drive must come off to diagnose it further.

Rod"
 
"just fixed it..at the other e

"just fixed it..at the other end of the lower shift cable, inside of the outdrive, where it connects to a slider, there was a hex bolt that held the cable in place, and just my luck the bolt fell out. but was a simple fix with some lock-tight. (problem solved)"
 
Lets see:
did you have a manu


Lets see:
did you have a manual when you dropped the lower
did you read the manual before you dropped the lower.
Was the lower unit IN FWD GEAR when you reassembled it along with the control box.
Did you remember to install the SS washer on the shift shaft in the lower unit.
 
"That so called hex nut cannot

"That so called hex nut cannot be tightened on the core, the slider must be able to rotate.Once set the safety wire holds the set screw in place."
 
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