Alpha One Trim/Limit wire Polarity?

[Grumman59]

I've just replaced the trim sender and trim limit switches on my 1986 3.0L Alpha One but I have a problem when it comes to connecting the leads at the engine side because the new leads are not color coded as the old ones were.

I bought a Mercury Quicksilver sender kit #805320A03. The instruction leaflets omit any information regarding engine wiring connections.

The new sender (stbd.) has a male and a female plug but includes the option to add screw lug adapter extensions, which is what my engine uses. The original wires had a brown and a black sleeve but the new wires are unmarked so I don't know which way they go.

The new limit switch (port) just has two male plugs, also not color coded. The original engine loom has a blue and a purple sleeve.

So before I try this and smoke all the wiring, can someone please point me in the right direction regarding these connections. Maybe the limit doesn't matter but I imagine the sender would, being a potentiometer.

 

[boat127]

Re: Alpha One Trim/Limit wire Polarity?

it doesnt matter which one goes where its just continity. but you could look at your old sender and see which wire end is and corospond it to your new sender. theres not power to the switches

 

[JustJason]

Re: Alpha One Trim/Limit wire Polarity?

theres not power to the switches

That's not true at all, sure there's power that runs through it, how else does a variable resistor work???

Grumman- It's low voltage, so you don't have to worry about shorting anything out. Just hook up the wires and look at the gauge, if you have the wires backwards then the gauge will move in the opposite direction than it's supposed to.

 

[smokeonthewater]

Re: Alpha One Trim/Limit wire Polarity?

well actually that isn't true either...... the reason polarity isn't marked is because it makes no difference how you hook it up reversing the wires will NOT reverse the guage.... resistance is resistance..... what you DO need to watch is getting the limit switch and sender hooked to the right connections but polarity does not matter here

Also low voltage or high voltage makes no difference as to risk of damage from "shorting out" or reversing polarity on electrical connections..... This was a perfectly valid concern and it is always a good idea to verify before making a connection you are unsure of reguardless of the voltage

 

[Grumman59]

Re: Alpha One Trim/Limit wire Polarity?

Thanks, smokeonthewater , you confirmed what I suspected.

Ha, I got that dreadful top screw tightened back up in the transom where the leads go through after a lot of difficulty. Then later I was at the Mercury dealer for something else and the tech there was doing the exact same job on another Mercruiser.

When I mentioned that top screw, he said they just leave them out. So much for my $0.50c/hour labor against their $100/hour+tax.