1988 Mercury 150 Black Max Temp Horn

[spocter72]

Hello All, I have a couple of questions on this motor. I am new to this and need some help. I bought a boat with this motor,but alll the wiring was gone to the motor.I put a new wire(harness) to the motor,and have everything working except the temp horn. I think I really need that. Could someone please tell me how to wire the temp horn from scratch? ALSO,the controller to put it in gear and accelerate seems to start to rev it up before it goes in gear too much.I need to make it engage before it revs up. Could you please tell me how to do that. Engine to best of my ability is a 1988 Mercury Black Max 150 Serial OB251602 on a 1988 Bayliner center console.Any help is deeply appreciated. Thank You ALL so very much....Len

 

[gss036]

Re: 1988 Mercury 150 Black Max Temp Horn

I think the best bet would be for you to buy/find a Mercury OEM manual for that engine. Sometimes you can find them on E-BAY/ Craigslist, etc.
The shifting/reveving problem can most likely be solved with what is called LINK&SYNC and you really should have a manual to follow to do it. The Temp sensor wiring is realitive simple and if you bought a wireing harness the wires are already there, you just have to follow the wire schematic for the tan/brn wires. One side of the head should have an overheat alarm, the other a temp sensor for a guage. You should also install a water pressure guage, that way you know you have water running through the engine.

 

[spocter72]

Re: 1988 Mercury 150 Black Max Temp Horn

Thank You Commander for the reply. I think I got the reving issue under control.I really didnt get a wiring harness,but a length of cable with the right colored wires in it. I dont have a wiring schematic which is why I asked here.Do you have or know where there is a schematic that I colld use to wire it.You are right though, I do need a manual.I just discovered my batteries are not charging either.Thanx Again...Len

 

[spocter72]

Re: 1988 Mercury 150 Black Max Temp Horn

On the temp horn, I am going to guess and say Tan wire from sending unit to one side of horn (for neg) and the other side of horn to keyed positive. Would this be right, or even close? Thanx Again

 

[j_martin]

Re: 1988 Mercury 150 Black Max Temp Horn

On the temp horn, I am going to guess and say Tan wire from sending unit to one side of horn (for neg) and the other side of horn to keyed positive. Would this be right, or even close? Thanx Again

Ya got that one right. If it has an oil alert module on it, it wires to the same horn. They come together at a terminal strip high on the starboard side.

hope it helps
John