temp sender help on 150hp v6

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
hey guys,

you were all so helpful and knowledgeable with my last question i thought i would ask again.

I have a 1990 ish mariner 150hp v6 carb.

P310710_19380001.jpg


wrong side, but may help a bit!

P310710_19580001.jpg


its all up and running and boy does it run! :cool:

i have been reading up and this is what i think it correct.

tan/blue wire which runs through the main harness and up through the tacho harness is for the auxiliary warning lamp.

the control has a built in buzzer, although i can't see one. its a quicksilver commander type think. but it must be in there somewhere.

the tan wire is for the sender to the water temp gauge. this is on the engine somewhere and not on the harness. any idea where on earth it would be? i run a seperate wire fo this to the gauge.

so. am i right in thinking once i find the tan wire i connect that to the gauge. the tan/blue i should wire into a lamp (my gauge has no warning lamp built in). when the lamp lights it means the engine is overheating.

I appreciate your time and help.

Regards, Steve
 

j_martin

Admiral
Joined
Sep 22, 2006
Messages
7,474
Re: temp sender help on 150hp v6

Yer on it, poor boy:D

The tan/blue wire goes to ground when alarm sounds, either oil alert or overtemp. You can wire it to a loud sonalert, or a lamp or led. It is the negative lead. Positive from the lamp or sonalert goes to battery switched (purple) through an appropriate fuse, probably 5 amp.

The tan wire comes from the temp gauge sender on the engine, on the other head than the OT sensor, at about the same position. It should thread around the starboard side of the engine and connect to a bullet connector that goes into the boat harness on the boat side of the cannon connector. The next time it surfaces is coming out of the back of the forward controls on the instrument harness. It should still be tan.

Sure, that gauge will work. Just duct tape it to the dashboard. :D

hope it helps
John
 

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
Re: temp sender help on 150hp v6

cheers mate. very helpful. i had a real good hunt for the tan wire and i think i fond it, but the wires all fairly old now so brown and tan look similair! as does tan/blue :redface:.

i will take a look next time i'm at the yard and will take a photo as i don't want to get this wrong! boats are so different to cars :)

also while i am at it....should i fuse my gauges? i guess 5amp off the main purple harness wire coming up to the dash?

just need to find some cheap place to buy duct tape now. :D
 

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
Re: temp sender help on 150hp v6

not mine ut mine is almost identical. is it the heighest screw about the yellow wire? do i simply add a wire from that screw back to the gauge?

thanks again.

motor1.jpg
 

j_martin

Admiral
Joined
Sep 22, 2006
Messages
7,474
Re: temp sender help on 150hp v6

Normally that is the overtemp alarm wire. If you ground it, the alarm should sound.

Follow it to the sender, then go to the identical postion on the other head and find the temp gauge sender. Follow wiring back toward the boat. Maybe the sender is totally missing.

On my 88 XR4, the OT switch is on the starboard head. From there a black wire goes to the screw terminal above the switchboxes, along with a tan wire from the oil alert, and a tan/blue wire from the harness. That's the buzzer circuit.

On the port head is a similar device, with a tan wire that routes across the top of the engine, and along with the other wires aft the switchboxe, and thence to a bullet connector under the switchboxes and into the boat harness on the boat side of the cannon plug. That's the temp gauge circuit.

hope it helps
John
 

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
Re: temp sender help on 150hp v6

Normally that is the overtemp alarm wire. If you ground it, the alarm should sound.

ok, that makes sense as it follows through the main harness and ends up as the blue/tan poking out of my control box.

On the port head is a similar device

looking at my first picture it appears to be missing. i'll have a good look when i o to the boat next.

thanks for our help
 

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
Re: temp sender help on 150hp v6

again, not my photos or engine, but...

below top spark plug is the sender for the buzzer? i have this on mine and goes to the tan wires we were discussing earlier

merc2.jpg


below top spark plug is temp gauge sender?

merc1.jpg


if so then looking at my picture and from memory i think it is missing from my engine. sqint!

P310710_19580001-1.jpg


if it is missing what can be done to make a new one work somehow?

cheers again, steve
 

j_martin

Admiral
Joined
Sep 22, 2006
Messages
7,474
Re: temp sender help on 150hp v6

Yep, Missing.

If you look at the harness near the cannon plug, you should find a female bullet connector on a tan wire dangling.

Sender is a commodity part. Either stock or aftermarket.
 

Attachments

  • Port Side.jpg
    Port Side.jpg
    37 KB · Views: 2

steve bain

Cadet
Joined
Jun 3, 2010
Messages
9
Re: temp sender help on 150hp v6

now i know where it should be i can sort this out now. thank you very much for all your help. you are a wealth of knowledge. steve
 
Top