Late 80s mercury Blueband 75

warwicksail

warwicksail

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Carmarthen West Wales UK
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A friend has a old 75 hp mercury blueband which runs like a dream, Except when it stops all together lol... this only happens if the prop comes out of the water then seems to cut out the electrics and wont restart.

I have heard mentioned that there is a cut out device which can be removed.

Anybody have anymore info on this ...

Paul
 
If you tell us the year (or provide a pic) we can comment in more detial but most of them had a mercury switch that would earth the ignition LT (like a killcord) if the engine tlted up. It had to tilt quite high to activate this switch.

It sounds like the blob of mercury isn't flowing right in yours, or the switch has some other fault. The switches were fairly relaible although some people did just override them. I vaguely remember one failing on me and I bought another, eons ago.

Anyway, if you know what you're doing, it's ok to override the switch. It's easy to find becuase it looks just like you'd expect a mercury switch to look , mercury chamber about an inch long, and mounted with one set screw at an angle, iirc at the top of the plate with all the ignition coils and stuff, though I'm working from memory 20ys ago. It will have 2 low tension wires, and to bypass the switch you just ensure the wires are not connected.

Firefly625 might be able to chip in more on this too
 
thanks jfm.... /forums/images/graemlins/confused.gif

...as you say, I should be able to help, but all I can think of is the same as you, but really not sure why it would not re-start after engine (and boat!) settle back in the water.... here are couple of pics. I must say have never had any issue with the anti-tilt switch & I have never had to worry about what or where it is, but firstly see pic of my 80hp Blue Band merc, mercury switch I believe tucked to the left of the CDI pack, quite low down and practically hidden. But I believe may be clearer to view on my 50hp brown band where its top right of starter....

Certainly sounds sensible to bypass / change that. If that does not work I would suggest wiring to kill switch on control may be suspect, I have heard of that before..... also would suggest why doesn't re-start.... although I assume it does at some point!

n518639107_2529426_7489405.jpg


n518639107_2529411_2892880.jpg
 
Yup. The first picture is a 1970s engine, before they went to separate ignition coils and stuff around 1980. That engine has quite a lot of "non original" wiring btw, I mean some of Mercury's original loom has been replaced.

The second pic must be your brownband, mid 1980s ish. That engine has the 4 separate coils and no mechanical distributor device for the ignition. And yes the mercury tilt switch is the black tubular thing mounted top right of the starter motor in your picture, at about 45deg, held on by one philips panhead screw
 
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That engine has quite a lot of "non original" wiring btw, I mean some of Mercury's original loom has been replaced.

[/ QUOTE ]

...not wrong there! but it is 30 years old...its really had its time, just idiots like me who keep them going! /forums/images/graemlins/smile.gif
 
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