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Neutral safety switch versus shift kill switch?

Pal

Contributing Member
Hi, New guy here. I have an 81 Searay sedan, new to me. It would usually not start (nothing, no click, just dash lights) until you wiggled the shift lever, says the PO. Then it would start normally and run fine.
So, I took out two switches, the first because I thought it was the Neut safety switch, and the second because it really was the neut. safty. sw. (according to pictures)
Now the boat starts better, but I'm wondering :
what was the first switch I took out? It was up under the shift lever on an older Morse Marine dual console (ds twin I think they're called) , and was a thin plastic tube with two wires plugged onto it. It seems to act like a plunger when the lever is moved, so it's not contacting inside unless the shifter is in neutral.
The second one I disabled looks like the online pictures of a NSS, it was on the tranny and was supposed to push in when you were in neutral.
what you think so far? Where's the switch that shuts off the engine while you're shifting? Cornfused.. :) Thanks
 
both operated while it was in neutral only ? One i would have thought was a man over board switch, with a lanyard that might be missing.

See you attach the lanyard to the man at the helm and if he fell overboard the switch would get pulled and the boat dies.

The other one would be to allow the boat to start only when the boat was in neutral.

You didn't give any info year, motor, anything else that can help us help you.

Got a pic of the control and the switch's ?
 
First question..........We are glad you have a 81 sea ray sedan...........Does not mean diddlysquat to anyone here.............what engines, drives, transmissions, DO YOU HAVE!!
Is it mercruiser??????Is it some other manufacturer?

Is this boat equipped with inboard motors with transmissions and a prop shaft going thru the boat to a prop? Or do you have outdrives?

If you have inboards then NO shift interuptor switch.

Only ALPHA series outdrive use a shift interuptor switch. Bravo's do not......Inboard's do not.
 
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Based on the Morse control box, the 'transmission', and the second switch, it's an inboard setup.

On that setup, the gear's NSS is usually the only active one. Some manufacturers will hookup the one in the control but that is a rarity. if they are both used, they should be in series. in that case, either one being open (or failing) will disable the starter circuit.

Like Kghost said, no shut-off switch is used for shifting an inboard. They usually don't have the lanyard activated kill switches either.
 
Hi, thanks for your responses. I was in the "sterndrive " section so I thought... Anyway it's a single sterndrive, like I said Mercruiser 454. It's an '81 srv255. I don't know what model outdrive- I think it's a "mercruiser" outdrive, before the Alphas etc (?) .
both operated while it was in neutral only ? One i would have thought was a man over board switch, with a lanyard that might be missing.
See you attach the lanyard to the man at the helm and if he fell overboard the switch would get pulled and the boat dies.

yes, I could see that, (good idea) but this is a completely buried tube that has no contact with the outer part of the shift box/levers. You have to disassemble the shifter and throttle and pull the thing up to even see it. It's a white plastic tube thing which connects from shift rocker-arm down to a fixed point below. It's about five inches long. Has two electrical connectors and sllides inside to make connection or cut connection. I will look at trying to get a picture of it up. Don't know how yet.
That's the curious one, cause I'm sure the other one is indeed a "neutral safety switch" according to pictures I've seen online.


 
First question..........We are glad you have a 81 sea ray sedan...........Does not mean diddlysquat to anyone here.............what engines, drives, transmissions, DO YOU HAVE!!Is it mercruiser??????Is it some other manufacturer?Is this boat equipped with inboard motors with transmissions and a prop shaft going thru the boat to a prop? Or do you have outdrives?If you have inboards then NO shift interuptor switch.
Only ALPHA series outdrive use a shift interuptor switch. Bravo's do not......Inboard's do not.

Hi, Have a 454/330, but don't know the model tranny or outdrive. They are both Mercruiser tho. (This was the Mercruiser sterndrive forum?)
I have to find out what model of outdrive/tranny. So, no interruptor switch on some of them? good. Thanks, Pal
 
Based on the Morse control box, the 'transmission', and the second switch, it's an inboard setup.On that setup, the gear's NSS is usually the only active one. Some manufacturers will hookup the one in the control but that is a rarity. if they are both used, they should be in series. in that case, either one being open (or failing) will disable the starter circuit.Like Kghost said, no shut-off switch is used for shifting an inboard. They usually don't have the lanyard activated kill switches either.

Some manufacturers will hookup the one in the control but that is a rarity. if they are both used, they should be in series. in that case, either one being open (or failing) will disable the starter circuit.

Interesting. Maybe that's why when I took only one of the two out the boat still wouldn't start...I'll keep you posted if I ever figure out what it was, but if it's possible that there are two safety switches then maybe that's it.. I'll try to figure how to add pictures to this site, thanks! Tim
 
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In your first post you did not say it was a inboard / outboard. There is no transmission. All the shifting is done in the lower unit of the leg.

In the lower you have a forward and reverse gear. The upper is where the power of the motor gets reduced 2 different size gears understand. There is no shifting up and down as in a auto,

There is a shift interuptor switch. When you place the throttle in forward the switch does not activate it activates when you come out of gear. The gears are backcut in your drive, and it has a clutch dog system. Follow the shift cable to the motor see it connect to the shift converter, there will be a micro switch that sits in a v notch. That is the switch. Have someone else move the throttle and you watch the motor the carb will move and the arms will move. The arms are the converter.

Concerning the throttle on a 81'. Without a pic i can't be sure the one on your boat is original to your setup.
 
I'll try to figure how to add pictures to this site, thanks! Tim
If you use the "quick reply" button at the bottom of the page it will let you upload a picture with your message. Along the top are some icons. The seventh from the left, next to the globe with the little chain link icon is the "insert image" icon. Click on it and it will open a box that is titled "add an image from your computer". Just find the pic(s) you want to load and add it. Close the box when you are finished and they will appear in your message on the forum.

You can also use the more advanced "+Reply to Thread" button. The same load picture icon will appear on this new page and you do the same procedure to upload pics.
 
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Sounds like you need a new shifter if it's an '81 and original to the boat. These things don't last forever! It's probably a Morse or Uflex rebranded as Mercruiser. They can get finicky as they age as they have the neutral switch as well as the trim switch built in. It's probably not cost effective to repair as they often need parts that are NLA, and even when repaired are still 30 years old and doing you no favors at this point.
Best bet is to replace with a new Teleflex. This one is a CH1700:

114690F-f.jpg


It will retrofit perfectly and give you no hassles. There are a number of side mount models which are available from our hosts, and many other on line retailers. While you're at it, put in new cables. the Teleflex 3300 extreme cables are smooth and very high quality.
I tend to stay away from Uflex not because they are Italian, but they seem to be harder to find parts for.
Kobelt controls are the gold standard if you want top of the line. Buttery feel and built to outlive the owner...by several generations.
 
this sounds like a tr/ trs setup. used an inboard transmission coupled to an outdrive. the switch at the trans. would be the nuet. safety. the other you described doesn't sound familiar. post a pic when you can. there was no shift interupt on these.
 
Hi, Thanks for the responses. It is a SRV255, which is 25.5 feet at the waterline and 27 feet overall. I'm pretty sure it is the TR, It does seem to have a "transmission". It is not just a motor and outdrive. The trans looks sort of like a bell housing or short stubby car transmission, on the end of the block, between the outdrive and block.

There is a shift interuptor switch. When you place the throttle in forward the switch does not activate it activates when you come out of gear. The gears are backcut in your drive, and it has a clutch dog system. Follow the shift cable to the motor see it connect to the shift converter, there will be a micro switch that sits in a v notch. That is the switch. Have someone else move the throttle and you watch the motor the carb will move and the arms will move. The arms are the converter.
I'll look for it this weekend. Engineers amaze me.
 
this sounds like a tr/ trs setup. used an inboard transmission coupled to an outdrive. the switch at the trans. would be the nuet. safety. the other you described doesn't sound familiar. post a pic when you can. there was no shift interupt on these.

Hi, yeah all pictures of a NSS on the net look just like what I wired with the button in "closed" (and so disabled- makes the ignition think it is always in neutral so it will start) at the transmission (NSS). I'll try to upload a pic of the other one, because I did take one last week.
My Shift / throttle is a Morse Marine dual shifter, one of those nice old looking chrome ones. Model looks like an "SR Twin" in the pictures. I think it's original and yes, maybe needs repalcing. Glad to know you can retrofit a newer one on. Thanks everybody, Pal
 
They can get finicky as they age as they have the neutral switch as well as the trim switch built in.

yes, seems finicky. Stiff, balky. Mushy detentes. I would love to at least replace cables. Is that a big job? I have outdrive-trim separate on those black round buttons, and also trim-tabs on separate rocker switches.

Kobelt controls are the gold standard if you want top of the line. Buttery feel and built to outlive the owner...by several generations. Damn that sounds nice!
 
Thanks that works well except the picture is too big apparently. I get the red X saying so. Hmm wonder how to make the picture less big of a file..
 
According to the info available and also from what the folks on the Searay forum told you, it is apparent that you have the TRS drive. This uses a Borg Warner Velvet Drive transmission connected to a non shifting drive leg. Your shift levers are Morse SR. Nothing wrong with those as shifters go but they tend to get sloppy as they age and rebuilding them is just as much trouble as replacing. It would seem that you have twin shifters one for FNR and the other for throttle. Or you have twin engines? Can't tell from my chair.
There are almost too many choices if you decide to update the shifters. You can install push pull like you have now, electronic "fly by wire", or hydraulic. All have their pluses and minuses. You can't go too wrong with just new cables and a direct replacement of what's there now. Ballpark on the cables is about 60 each and the shifters are about 270 for the top mount SL-3 from teleflex:
63341F-p.jpg

Or from Kobelt the 2091 at about $900

116744F-p.gif

This one needs the neutral safety switch at an additional $90 and the cable connector kit for 30

If you go hydraulic prepare to spend in the 2-3000 range for single station single engine. Electronic controls will be slightly more at about 3500.

If you have two steering stations add another control and two more cables and if you have twin engines multiply by two
 
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It would seem that you have twin shifters one for FNR and the other for throttle. Or you have twin engines? Can't tell from my chair.
ha ha sorry, yes one engine with two helms (inside and flybridge) and the shifters are both "twin SR" = two levers, with a black knob shifter fnr, and a red knob throttle.
Welp I'm going out this weekend and will know more soon. I'm thinking maybe cables wouldn't be too much, and try keeping the existing shift sets.
I am having difficulty figuring the difference between the TR and TRS models, altho they are supposed to look different. Wonder what the "history" is of the difference.
Thanks for the help and pictures, Pal
 
TR= "transmission" model
TRS="transmission sport" model

Yes a TR can swing up to a 20" dia.
prop ( kind of like the Bravo II lower)

here's something...
 
[SIZE=+2]TRS / TR Drives[/SIZE]
[SIZE=+1]L[/SIZE]ots of TRS drives are still operating out there!
They are very large and very tough. The main draw-back of the TRS drive was that it needed a transmission as no shifting occured in the drive itself.
[SIZE=+1]N[/SIZE]ewer and faster boats needed less weight and more room so the TRS has been discontinued by Mercury Marine and it's market replacement is the Bravo series.
[SIZE=+1]T[/SIZE]he TRS initially was mated to Mercury Marines TRS transmission. This was Mercury's own design which used some Ford inner parts. The tranny had an internal oil cooler and an aluminum housing.
Mercury then changed to the Borg Warner Transmission which required that the TRS Drive input shaft be a splined male shaft instead of the older, hollow female splined shaft.
When ordering TRS stuff, make sure you specify what tranny set-up you have.
[SIZE=+1]T[/SIZE]he TR drive used the same upper driveshaft housing as the TRS but it's lower housing and propshaft were much larger for larger props. here's some more...
 
I was confusing the Morse SR with the Twin S, my bad. They are great shifters. My own choice of shifter is the Morse SR. It has a smooth feel like the Kobelt but uses far cheaper pot metal castings that are coated to protect them from corrosion. The pivots slide on nylon bushings, which are easily replaced. (Mcmaster Carr has them) The detent is a ball and spring arrangement and it is a good idea to replace them. They also need to be greased. Ongaro makes replacement arms in stainless steel (Defender, $112) with a set of anodized aluminum knobs, a very robust and attractive mechanism. I have these installed on both steering stations. They are connected in series, that is, the flybridge controls are connected to the lower station controls which are connected to the engine. I have 3300 series cables between all. I used nylon ball joint ends from Mcmaster Carr. Item #1064K711.
There is only one kind of neutral safety switch available for these, so whatever is going on with your shift levers is likely related to the switch being out of adjustment. I have had a similar experience using the older red jacket cables which are far stiffer than the 3300 ones. The old cables had to bend rather sharply right at the bottom of the shifter, and the pressure from this bend was not allowing the safety switch to disengage. Replacing the cables with the newer type that have a better bend radius took the pressure off the end of the cable and the switch was free to operate properly.
The neutral safety switch that you get from Teleflex that fits on the shifter has three spade connector fittings. One is start power, the other goes to the start solenoid and the third is a warning lamp feed.
Apparently there is not a NSS on your transmission, or it was not used if it is there. In any case the safety interlock that keeps you from being a doofus needs a bit of tweaking but that's probably all there is to your problem.

Read this:
http://www.teleflexmarine.com/wp-content/uploads/2010/05/SR_neutral_safety_switch.pdf

And this:
http://teleflexmarine.com/wp-content/uploads/2010/04/SRControl-usa-data.pdf

These are the cables you want:
http://www.teleflexmarine.com/produ...ntrol-cables-and-accessories/tfxtreme-cables/

All of these parts are available from our host.
 
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Pal, try using the "reply with quote" feature when you are quoting a member's previous comments.
Much easier this way, and you can edit out non-relative comments, and we will know who said what!

The neutral safety switch will interrupt the starter motor solenoid circuit only!
My question is, since you say 81 Searay sedan....... Is this a dual station boat? My guess would be YES!
 
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Pal, try using the "reply with quote" feature when you are quoting a member's previous comments.
Much easier this way, and you can edit out non-relative comments, and we will know who said what!

The neutral safety switch will interrupt the starter motor solenoid circuit only!
My question is, since you say 81 Searay sedan....... Is this a dual station boat? My guess would be YES!
Ok, thanks, I'll do that. Yes It;s a dual station (see above) inside and flybridge helms. Thanks!
 
I was confusing the Morse SR with the Twin S, my bad. They are great shifters. My own choice of shifter is the Morse SR. It has a smooth feel like the Kobelt but uses far cheaper pot metal castings that are coated to protect them from corrosion. The pivots slide on nylon bushings, which are easily replaced. (Mcmaster Carr has them) The detent is a ball and spring arrangement and it is a good idea to replace them. They also need to be greased. Ongaro makes replacement arms in stainless steel (Defender, $112) with a set of anodized aluminum knobs, a very robust and attractive mechanism. I have these installed on both steering stations. They are connected in series, that is, the flybridge controls are connected to the lower station controls which are connected to the engine. I have 3300 series cables between all. I used nylon ball joint ends from Mcmaster Carr. Item #1064K711.
There is only one kind of neutral safety switch available for these, so whatever is going on with your shift levers is likely related to the switch being out of adjustment. I have had a similar experience using the older red jacket cables which are far stiffer than the 3300 ones. The old cables had to bend rather sharply right at the bottom of the shifter, and the pressure from this bend was not allowing the safety switch to disengage. Replacing the cables with the newer type that have a better bend radius took the pressure off the end of the cable and the switch was free to operate properly.
The neutral safety switch that you get from Teleflex that fits on the shifter has three spade connector fittings. One is start power, the other goes to the start solenoid and the third is a warning lamp feed.
Apparently there is not a NSS on your transmission, or it was not used if it is there. In any case the safety interlock that keeps you from being a doofus needs a bit of tweaking but that's probably all there is to your problem.

Read this:
http://www.teleflexmarine.com/wp-content/uploads/2010/05/SR_neutral_safety_switch.pdf

And this:
http://teleflexmarine.com/wp-content/uploads/2010/04/SRControl-usa-data.pdf

These are the cables you want:
http://www.teleflexmarine.com/produ...ntrol-cables-and-accessories/tfxtreme-cables/

All of these parts are available from our host.

fantastic info, I'll get back to you on some of this..
 
I was confusing the Morse SR with the Twin S, my bad. They are great shifters. My own choice of shifter is the Morse SR. It has a smooth feel like the Kobelt but uses far cheaper pot metal castings that are coated to protect them from corrosion. The pivots slide on nylon bushings, which are easily replaced. (Mcmaster Carr has them) The detent is a ball and spring arrangement and it is a good idea to replace them. They also need to be greased. Ongaro makes replacement arms in stainless steel (Defender, $112) with a set of anodized aluminum knobs, a very robust and attractive mechanism. I have these installed on both steering stations. They are connected in series, that is, the flybridge controls are connected to the lower station controls which are connected to the engine. I have 3300 series cables between all. I used nylon ball joint ends from Mcmaster Carr. Item #1064K711.
There is only one kind of neutral safety switch available for these, so whatever is going on with your shift levers is likely related to the switch being out of adjustment. I have had a similar experience using the older red jacket cables which are far stiffer than the 3300 ones. The old cables had to bend rather sharply right at the bottom of the shifter, and the pressure from this bend was not allowing the safety switch to disengage. Replacing the cables with the newer type that have a better bend radius took the pressure off the end of the cable and the switch was free to operate properly.
The neutral safety switch that you get from Teleflex that fits on the shifter has three spade connector fittings. One is start power, the other goes to the start solenoid and the third is a warning lamp feed.
Apparently there is not a NSS on your transmission, or it was not used if it is there. In any case the safety interlock that keeps you from being a doofus needs a bit of tweaking but that's probably all there is to your problem.

Read this:
http://www.teleflexmarine.com/wp-content/uploads/2010/05/SR_neutral_safety_switch.pdf

And this:
http://teleflexmarine.com/wp-content/uploads/2010/04/SRControl-usa-data.pdf

These are the cables you want:
http://www.teleflexmarine.com/produ...ntrol-cables-and-accessories/tfxtreme-cables/

All of these parts are available from our host.


I would love to see a PDF like you sent here for the Twin S! I haven't been able to get there yet!
Mine did NOT have the additional small black box/miniswitch/neutral safety switch like they show here. Either someone had already taken it off or...? It ONLY had the tube you see in the diagram. White plastic tube. But that tube had two electrical contacts (spades and wires) coming right out of it.
 
fantastic info, I'll get back to you on some of this..

have had a similar experience using the older red jacket cables which are far stiffer than the 3300 ones. The old cables had to bend rather sharply right at the bottom of the shifter, and the pressure from this bend was not allowing the safety switch to disengage. Replacing the cables with the newer type that have a better bend radius took the pressure off the end of the cable and the switch was free to operate properly.
yes I have "Red Jacketed" cables, maybe they're the stiff ones.
I'm going to look harder at what is supposed to be the detent stiffness screw. See if I can figure how it could work. It's high up on the lever..? Can't figure how it would work I guess without looking at it.
 
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