1985 Merc 50 tiller suddenly no electric start

[AZDave]

Hi All;

Searched for an answer here, but couldn't find. Unit was starting like a champ. Turned engine off at boat ramp, and suddenly nothing happens when i turn the key. It is like the engine is not in neutral, when in fact it is.

removed lower unit and made sure gears were matching, put together in neutral, and still nothing. The choke will respond, the battery is fine.

behind the switch, all wires are sound and firm.

Any ideas are greatly appreciated. Thank you.

Dave

 

[AZDave]

Re: 1985 Merc 50 tiller suddenly no electric start

Maybe specifically: the throttle has a switch to detect neutral > where is it? and how do I go directly to starter and try with jumpers: which leads?

 

[oldman570]

Re: 1985 Merc 50 tiller suddenly no electric start

The following link is a wiring diagram for the motor,
http://boatinfo.no/lib/mercury/manuals/40-50-55-60.html#/102
being that the choke solenoid works then the fuse that is on most of the primary 12 Volt + cable should be good. The neutral safety switch should be in the shift linkage area and it has the one wire that is wired to the block - battery, and another that is wire to the - small post of the starter solenoid. If you jump the starter solenoid with a jumper from the large + battery post to the small solenoid post with the red wires on it, the motor should start when the key is turned to the on position. If it will not turn the motor over then jumper the other small post to the - battery cable and see if it will spin over. The neutral safety switch supplies battery - to the solenoid so the motor will spin over and start. Chances are that the neutral safety wire to the block or the one to the starter solenoid are corroded and not making a good connection. Clean all the wire connections shiny and coat with dielectric grease or liquid rubber to keep the connections from corroding.
JMO
Oldman570

 

[AZDave]

Re: 1985 Merc 50 tiller suddenly no electric start

The following link is a wiring diagram for the motor,
Boatinfo - Mercury Service Manual for 40-50-60 hp
being that the choke solenoid works then the fuse that is on most of the primary 12 Volt + cable should be good. The neutral safety switch should be in the shift linkage area and it has the one wire that is wired to the block - battery, and another that is wire to the - small post of the starter solenoid. If you jump the starter solenoid with a jumper from the large + battery post to the small solenoid post with the red wires on it, the motor should start when the key is turned to the on position. If it will not turn the motor over then jumper the other small post to the - battery cable and see if it will spin over. The neutral safety switch supplies battery - to the solenoid so the motor will spin over and start. Chances are that the neutral safety wire to the block or the one to the starter solenoid are corroded and not making a good connection. Clean all the wire connections shiny and coat with dielectric grease or liquid rubber to keep the connections from corroding.
JMO
Oldman570

Thank you Sr 570. Much appreciate. Will get into looking further this weekend. This dry climate can make wires quite brittle and erode. makes sense.

 

[AZDave]

Re: 1985 Merc 50 tiller suddenly no electric start

Found the switch! cable running from bottom shift linkage is supposed to pull down on neutral to make connection - it does not move at all in any shift movement. appears to not be connected, broke fell off, not sure and cant see it. To get to the connection, seems I need to pull off the carburetor...? Do you have a parts diagram for the switch/cable linkage.

It does turn over when I make the connection.

 

[oldman570]

Re: 1985 Merc 50 tiller suddenly no electric start

See your PM's at the top of the page.
Oldman570

 

[AZDave]

Re: 1985 Merc 50 tiller suddenly no electric start

See your PM's at the top of the page.
Oldman570

Thank you. Still can't locate actual cable part/connection. There is a cable that runs from the shift lever along the side of the motor housing, up to the switch. When in neutral is is supposed to pull a roller down to make contact with the switch, then when put in forward it forces the roller up. The cable does not move at all, so where it is connected must me broke, fell apart. But to get to that area of connection looks very difficult, lots of stuff in the way.

Question: Do you think it would be OK to relocate the switch, outside the housing so I can get at it and manually engage it? Or, instead of relocating, do you think I could bypass the switch so it is always ready to start, whether in forward, neutral or reverse?

Much appreciated your help on this.

 

[oldman570]

Re: 1985 Merc 50 tiller suddenly no electric start

It is best to fix the cable or replace any broken parts needed. The switch can be bypassed, but this can cause a lot more problems and accidents that is very hazardous in the long run, and NOT RCOMMENDED. The starter or the carb might have to be removed to get to the lower shifting controls and gain access to the bad parts, so the cable can be repaired or replaced. Here is a link that you can find just how the switch and the shifting linkage goes and works. http://boatinfo.no/lib/mercury/manuals/40-45-50-BIGFOOT.html#/590JMO
Oldman570

 

[AZDave]

Re: 1985 Merc 50 tiller suddenly no electric start

It is best to fix the cable or replace any broken parts needed. The switch can be bypassed, but this can cause a lot more problems and accidents that is very hazardous in the long run, and NOT RCOMMENDED. The starter or the carb might have to be removed to get to the lower shifting controls and gain access to the bad parts, so the cable can be repaired or replaced. Here is a link that you can find just how the switch and the shifting linkage goes and works. Boatinfo - Mercury Service Manual for 40-45-50-bigfoot
Oldman570

Thank you, thank you, thank you! Much appreciate and hope get er done.
Dave