Engine shifts into gear, hard to shift out of gear

greg82255

Senior Chief Petty Officer
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Hello,

I have a 1986 Merc 260/Alpha One. It shifts from neutral into forward or neutral into reverse without any problem, but getting it to shift from either forward or reverse into neutral is really hard. I have to pull on the shifter very hard, and one time I even jumped from forward right into reverse because I had to pull so hard. Also, this problem does not exist when the boat is running on the trailer- it only happens when it is in the water. The upper shift cable is brand new - recently posted a thread because I thought there was something wrong with that, but I replaced it and mounted it and the problem still exists. Not sure when the lower shift cable was last replaced. Any idea what may be going on here? Thanks in advance.
 

wire2

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Re: Engine shifts into gear, hard to shift out of gear

Your idle speed is too high. If you have an ESA, it's not working.
 

fishrdan

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Re: Engine shifts into gear, hard to shift out of gear

The shift interrupt switch is not working, it should stumble the engine coming out of gear, allowing the gears to un-mesh.
 

greg82255

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Re: Engine shifts into gear, hard to shift out of gear

The Idle speed is about 700 (I think 650-850 is normal?). I don't know if i have an ESA, how would I go about finding that out? I just installed a new electronic ignition system from Michigan Motorz and they told me to hook up the shift interrupt to the black wire coming from the distributor. Maybe that wasn't correct and the shift interrupt is disabled? Also don't know when the shift cable was last done but I have moved the shifter in and out of gear with my hand and using the shifter while off the trailer, engine both on and off, all with no problems. Only in the water is there a problem. The shift interrupt not working makes a lot of sense. How can I test if its working or not?
 

Bondo

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Re: Engine shifts into gear, hard to shift out of gear

The shift interrupt not working makes a lot of sense. How can I test if its working or not?

Ayuh,... Push the button, 'n the motor should Quit...
 

greg82255

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Re: Engine shifts into gear, hard to shift out of gear

Where is the button? All I know about the shift interrupt is that there's a green and white wire you need to connect to the distributor.
 

Bondo

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Re: Engine shifts into gear, hard to shift out of gear

Where is the button? All I know about the shift interrupt is that there's a green and white wire you need to connect to the distributor.

Ayuh,... At the Shift Plate, where the upper, 'n lower shift cables come together is the switch that stumbles the motor so the drive will come outa gear...
If you push the switch with yer finger, the motor should Stall...

If Not, you've got it wired Wrong..
 

greg82255

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Re: Engine shifts into gear, hard to shift out of gear

Alright, once the rain stops I'll go out to the boat check it out. There wasn't a wiring diagram provided with the manual, or even instructions to connect the shift interrupt on a Mercruiser - instructions were only provided for OMC motors. I had to call them and they just told me to connect the green/white wire as I posted above. Am I doing any damage by forcing this motor in and out of gear without the shift interrupt working..?
 

dubs283

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Re: Engine shifts into gear, hard to shift out of gear

Am I doing any damage by forcing this motor in and out of gear without the shift interrupt working..?

damage will occur if you shift out of say reverse and it passes neutral and flys into forward gear, that type of rapid shift could cause damage to the clutch dog teeth/ramped gear teeth in the lower half

there is undue stress on the shift cables/linkage/contoller/shift plate assy that may cause damage over time, but you will fix this and have no issues once you figure out the wiring or find the switch to be faulty
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

If you activate the shift interrupt switch by hand, does the engine run rough?
If it doesn't, and I bet it doesn't, I would bet your shift interrupt switch is wired wrong. Can you post a picture of your shift plate with the shift interrupt switch, terminal block and Y plate for the switch?
 

greg82255

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Re: Engine shifts into gear, hard to shift out of gear

I haven't been able to get out to the boat yet, as it is still raining here and it's docked about 20 minutes away from the house. As soon as I get over there (probably tomorrow) I will take pictures of the shift plate.

Don - I installed the Delco Ignition system from Michigan Motorz that you suggested - the same one I emailed you the instructions for about 10 days ago.

http://www.michiganmotorz.com/delco-voyager-marine-electronic-distributor-p-119.html

I mentioned that there were not directions for how to connect the shift interrupt for a mercruiser, only OMC, and I had to call them to ask how to connect it correctly. They told me to just take the plug with a single black wire coming from it, plug it into the distributor, and connect the black wire to the shift interrupt. I bet I either didn't do it right, or they gave me the wrong instructions. Could you tell me how to wire it correctly so I can attempt to fix the problem when I get to the boat? The boat is not at my house so I would like to go there armed with a few possible solutions.
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

I remember that now, I think what happened is their instructions a flawed. The Merc shift interrupt switch is set to ground, for the EST to work, it has to have 12V applied to it. I will get a picture and post what I mean here in a few minutes.
 

greg82255

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Re: Engine shifts into gear, hard to shift out of gear

Awesome, I'll be here. Thank you
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

I think what happened is this. With your Thunderbolt ignition, one side of the shift interrupt switch went to ground as in this picture.

attachment.php


You need to change that black wire from a ground to a hot wire. Wire it with a purple wire so it doesn't get hooked up wrong in the future and hook it up like this.

attachment.php
 

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greg82255

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Oct 26, 2009
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781
Re: Engine shifts into gear, hard to shift out of gear

That makes a lot of sense. I actually took another look at the instructions and they provide a wiring diagram for carbureted merc engines (exactly what I have) and it shows the black wire from the distributor connected to the green/white wire, and it says connect the other end (the black wire in your first diagram) to a 12V source, exactly what you just described. I'll pick up some purple wire and go over to the boat tomorrow. I'll re-post whether this fixes the problem, and I bet that it will. Thanks Don
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

I have an article on the easy shift

You do realize that the EZ Shift series drives were only used in 1965 and 66 don't you? That was 46 years ago. Things have changed since then.
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

I am new to this forum and seldom take my time on the internet,

Welcome to iboats 470 fan, you might want to take some time and look around this site. Might be surprised what you find. Especially in the stickies. Nothing wrong with trying to help, that's a good thing. Problem is, if you don't use the correct terminology for items or systems, how do you know the information you are repeating is correct? I have seen a lot of wrong information in magazine articles over the years, on many different subject.
 

dubs283

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Re: Engine shifts into gear, hard to shift out of gear

I have the article from December 1995 issue of trailer boats mag. OK to post here or do I need OK from the publisher? I saw on this forum other posts about the switch adjustment, so sorry if I offered information that is already here.

seeing as how there are two very detailed schematics already posted on this thread, and all the proper nomenclature and schematics for the specific switch/issue are readily available in the OEM manual, i don't see the need to post an article from an outside source about a system that may or may not pertain to the op's problem
 

greg82255

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781
Re: Engine shifts into gear, hard to shift out of gear

I finally got out to the boat today. I re-wired the shift interrupter switch exactly as the diagram above shows. Problem not quite solved.

Before I did any re-wiring, I started the boat and pushed the shift interrupter switch manually to see if it would kill the motor. Nothing happened, so obviously it was wired wrong, and this was causing my shifting problem.

After I re-wired the switch, I started the motor and went to the back of the boat and manually pressed the switch to see if the motor would stall. It did stall, but when I went to start it back up, it wouldn't turn over. Turns out when I pushed the switch, it blew the fuse going to the ignition switch. This leads me to think that the switch is not actually grounding the ignition as it should be doing, but rather just shorting something out and therefore stalling the motor. I put a new fuse and did the same thing just to see if the fuse was bad. Turned on the motor, pushed the switch, blew the fuse again. Did it one last time and blew it again. The fuses are 20 amps. Do I need a larger fuse now because the switch is drawing additional current? Or is something else going on here that is shorting the circuit and causing the fuse to blow?
 

Don S

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Re: Engine shifts into gear, hard to shift out of gear

This leads me to think that the switch is not actually grounding the ignition as it should be doing,

It better not ground.

You need to set yours up like the second diagram shows. The one with the purple wire filled in. That is how it needs to be. NOTHING GOES TO GROUND.

The first diagram shows you how the OEM system was set up. it will not work with the EST.
 
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