Shift Cable Adjustment and interrupter switch question

RaceCarRich

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2000 Bayliner Capri 1950, 3.0L. Starting up my second season as a boater. Went out on the lake. Boat immediately stalls going into reverse at light throttle. Going straight to high throttle reverse is okay.

I've done my forum searching and it appears that the pros/experts all say to change the lower shift cable while a few DYI'ers seem to have had luck fixing the problem with a shift cable adjustment. I want to try the adjustment as to me the lower cable seemed smooth when operated by hand and the boat has never had a shift cable bellow leak. I know the prior owner and doubt the cables have ever been touched before. Online I found several methods to adjust the cables but I went with https://www.youtube.com/watch?v=-s_tgevX2aI.

The only thing I found out of spec was the remote cable from F to R traveled 3-3/16" which is out of spec from 3" +/- 1/8". I can't believe the extra .062" (.031" in each direction) is going to have a lot of impact unless you tell me so.

The issue I had was that after all is back together (did this twice), with the engine off it wouldn't lock the prop in both F and R. I found that if I didn't include the 4 turns of preload (spinning the plastic barrel) on the remote cable, it did allow the prop to lock in both F and R when using the throttle handle. Perhaps this has something to do with the remote cable being slightly out of spec.

All adjustments I read talked about starting with the adjustable stud in the "bottom" of the slot. Comparing my setup to most of the other images, it appears that my assembly is upside down. The lower cable is on top and the remote and shift assist on bottom. Given this, can I assume that all the way up in the slot (where I found the stud btw) is actually the "bottom" of the slot and thereby the starting point?

I also wanted to see what the interrupter switch was doing so I unplugged it and put a meter on it. Granted it was approaching midnight and the rechargeable light was dying, but as I cycled through F to R and back, the switch kept reading open. I also pushed the switch plunger in with a little screwdriver and the circuit never closed. When is the switch supposed to make the circuit? Is it open in the neutral "V" and then again open on the high point of the cam (all the way in gear) and only completes the ignition grounding circuit on the ramp of the cam? What would be the symptoms of a bad switch? Boat has always seemed to sort of grind into gear a bit but I was told that was normal.

Lastly, is there any way to test all this in my driveway? I hate to tow an hour, pay a ramp fee, and then block the ramp because I can't get my boat into reverse.

Thanks
 

Bt Doctur

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the lower shift cable has the brass barrel that fits into the slot held in place by a cotter pin, the control cable is held in place by the stud and nut There is a test and adjustment procedure in the manual for the switch.Usually within a 1/8 inch of travel will cause the switch to read shorted. grinding into gear is normal, the switch is only used coming out of gear
 
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RaceCarRich

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As a reference, my set up looks like this guys, http://forums.iboats.com/filedata/fetch?id=7150828&d=1310847192 Its upside down compared to most images and the diagram in the manual. I'm sure its no big deal other than when adjustment procedures refer to the "bottom" of a slot which I think on mine is the "top" of slot.

I pushed the switch plunger in the full amount of travel and didn't seem to complete the circuit but I'll try again.

the switch is only used coming out of gear

how does a switch know what direction you are going in or is it only helpful coming out of gear but operates in both going in and out? Seems like a lot of complaints about stalling going INTO reverse attributed to the cables and switch. I want to make sure I understand how this all works.

Also, what would the symptoms be of a bad switch?

Thanks
 

Bt Doctur

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It would be almost impossable to come out of gear while in the water
 

Bt Doctur

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UntitledGR_zpsxdhzzqlv.jpg

Your ign system puts 12v into the dist to stumble the motor ,NOT A GROUND
 

Rick Stephens

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As a reference, my set up looks like this guys, http://forums.iboats.com/filedata/fetch?id=7150828&d=1310847192 Its upside down compared to most images and the diagram in the manual. I'm sure its no big deal other than when adjustment procedures refer to the "bottom" of a slot which I think on mine is the "top" of slot.

I pushed the switch plunger in the full amount of travel and didn't seem to complete the circuit but I'll try again.



how does a switch know what direction you are going in or is it only helpful coming out of gear but operates in both going in and out? Seems like a lot of complaints about stalling going INTO reverse attributed to the cables and switch. I want to make sure I understand how this all works.

Also, what would the symptoms be of a bad switch?

Thanks

First thing to do is read this post about how the shift interrupt works. Very simple really and very easy to test and set to spec once you know how it works.
http://forums.iboats.com/forum/engi...3-how-to-how-the-shift-interrupt-system-works

Next, if your shift cable is out of spec and travel is 3 3/16th, then you need to fix that. It probably comes from a worn cable housing and should be replaced. Your outdrive will be very hard to get a perfect adjustment when it is a full 1/8th inch over spec. It is possible you can set the reverse pin to make up for the difference, but maybe not.

If you have original lower shift cable then it may be the problem. The cable housing is what wears, a groove forms in the sheathing which effectively decreases inner cable travel. Has nothing to do with water intrusion. Has everything to do with a long metal cable sliding inside a curved housing. That groove will form right in the middle of a curve in the housing where the inner cable grinds away at the sheathing.

You cannot easily test interrupt system in the driveway just by shifting into and out of gear. It requires a load on the prop, which presses the gear dogs into engagement. Those dogs can't come out of engagement while under load. The above link describes it better than I.

Rick
 

RaceCarRich

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That's a great read. Am I correct in summarizing:

- system is designed to work with resistance in the cable which should only be present when shifting out of gear. The resistance overcomes the spring pressure and moves what I'm calling the plastic cam to engage the switch.
- the reason it effects boats going into gear is because of too much internal resistance of the cable creating the same effect?


Next question, am I correct to assume that the switch should always remain between the V of the switch activating cam when not under load (e.g. engine off) no matter what gear its in?
 

Bt Doctur

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No, it only moves when coming out of gear, in the water. No other time.
 

RaceCarRich

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I want to make sure we are on the same page because it sounds like you are saying yes to my question. The switch plunger should always be in the cleavage except when coming out of gear in the water. If its on a cam when shifting on the trailer, its a problem, correct?
 

Bt Doctur

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The switch plunger should always be in the cleavage except when coming out of gear in the water.
Correct

If its on a cam when shifting on the trailer, its a problem, correct?

Maybe, if the clutch dogs are not perfectly aligned shifting into gear it will trip the switch, if this happened rotating the prop should allow it to reset to the valley. Should this happen shifing out of gear on land , the cable is bad or there is corrosion at work
 
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RaceCarRich

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[SUP]I rechecked and my switch does work when the plunger is depressed.

I spent some time looking at things and with what you provided I think I get it. The lower cable barrel is mounted below (on mine) the fulcrum (big shiny bolt) for the plastic actuating cams so the push/pull resistance of the cable when coming out of gear causes the cam plate to slightly pivot around the fulcrum and move the cams to depress the switch. In reality, the entire mechanism is a balancing act between the force required to push/pull the cable and the force to move the cams which is dictated by the spring behind the cam plate.

While not possible to truly test, wouldn't the goal on the trailer be to be able to shift into both F and R and lock the prop into gear each way while never tripping the switch? At least is it safe to say that if you don't have that, you don't stand a chance of having it work?[/SUP]
 
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Bt Doctur

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While not possible to truly test, wouldn't the goal on the trailer be to be able to shift into both F and R and lock the prop into gear each way while never tripping the switch?

Yes, doing it on land the switch must not move. If depressing the switch makes the engine stumble then everything should be fine on the water
 

RaceCarRich

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I put a backyard McGyver fix in place that would probably get me thrown out of the forum but it accomplished the goal of being able to lock the prop into both gears while keeping the interrupter switch relatively centered and not tripping. I think that the force of pulling out of gear under load will still trip the switch but I won't be able to test in water for at least a week.

It seems that the experts are correct and its lower shift cable resistance that is the issue. While it moves smoothly by hand, it takes a fair amount of force towards the end of travel range and is enough to upset the works. I'd love to get through the season and if I'm keeping the boat, next winter I'd need to learn to do all 3 bellows, the trim limit switch (just got it working by cleaning inner contacts but the insulation is falling off wires), and the lower cable. Seems like a big spend as a percentage of the boat's value but would be a learning experience.

In any case, since I now realize that switch engagement is based upon lower cable resistance overcoming the resistance of the spring that sits behind the plastic cam plate (Y plate) and I can't decrease the cable resistance, the only way to get the system back in balance is to increase the spring tension. (Wouldn't it be great if they had a spring tension adjustment to compensate for cable resistance increasing with wear??). So my McGyver rig..... both spring arms provide tension when pushed against stops on the metal shift bracket.... so to increase spring tension, I RTV'ed a short piece of thick wall trans cooler hose over both stops so the spring would hit the stop sooner and have more spring tension. I know, I know, you can stop shaking your head now.

I will definitely report back if it works. Any guesses?
 

Rick Stephens

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I think you have to look at a boat, especially an older one, as a constant ongoing project to fix and repair these things to spec. While sure, you can up things like spring rate to compensate for a cable problem, you will find that change creates more wear and tear on the cable from the control handle and on the control itself. Plus no one can work on it, except you. If you start changing the spec you will start having weird cascading problems and no one any where will be able to help you fix them.
 

RaceCarRich

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I hear ya. I only wish the previous owner had done some maintenance so that everything wasn't due at the same time. I guess that comes with the territory and price point. If I'm keeping this boat, next winter everything will be apart & put back to spec. This winter I wasn't sure if I was going to keep it or upgrade so I only did the impeller. The previous owner never changed it (or even knew what it was) so it was 15 years old.
 
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RaceCarRich

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I promised to report back on how my improvised repair went. Was out on the Hudson River near NYC today and the boat shifted flawlessly. The interrupt switch only interrupted when it was supposed to (coming out of gear). When I do a transom service I will replace the cable but for now, it's fixed. Thanks to everyone for helping me understand how the mechanism works.
 

NHGuy

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Ol grouchy guy here. I understand what you did and the theory holds well.

I only hope your workaround doesn't grind up the gears in your drive .OE drives cost over $3k and the common aftermarket ones are $1200.
Please be smart and carry good anchors along with a full complement of safety gear since you are boating on a river.
I hope your rig holds out til you can fix it to spec.
 
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