what is this part? and what does it do?

[heyitswebb]

i have a 1985 merc 115hp outboard. I have noticed a wire that looks like it is burnt up and i am concered what could happen. It is a red wire that is connect to what i am calling one of the two power packs. on the bottom panel this red wire goes to a black square box that is mounted on teh back of the plate in front of the carbs. It has two other wires coming out of it. the 3 colors are white with a stripe, red , black. The red wire is the bad one. The motr is not running good and i hope this has something to do with it. I want to order the part online but i dont know what it is called. My local mercury dealer will not work on anything over 15 years old. I know I need to get a manual to identify parts and I will get one but for now I need an answer. If you know of a web site that has diagrams of componets I'd love to know about it. Thanks for the help I know you will give me on this. It starts and idles great but will not take off, I thought maybe a power pack problem but saw this burnt wire. thanks tim

 

[WillyBWright]

Re: what is this part? and what does it do?

That sounds like the rectifier. But I'm not so sure. There should be two yellow wires and a red to it. If the connection to the red was corroded, that could definately melt the insulation on the red. White with a black stripe should be the bias circuit on the switchbox or a trigger wire. Should have absolutely nothing to do with the rectifier! I have the feeling somebody that knew absolutely nothing about Merc wiring got in there and played with the connections. My sympathies! I wish I was closer to you! I live for such challenges.

 

[achris]

Re: what is this part? and what does it do?

Sounds like the idle stabilizer. The red wire is for the sensing of the engine speed (for the stator originally), the black is ground and the white with black stripe is the bias wire. The stabilizer alters the voltage on this wire (conected to the power packs) to increase the engine speed if it falls below about 550rpm. If the red wire is 'grounding' then it will cause one power pack to misfire.<br /><br />Chris.............

 

[heyitswebb]

Re: what is this part? and what does it do?

the idle stabilizer, what you said sounds right. sounds like the cause of my problem. the part has no part number or anything on it. How do I know what the part number is to order a new one? Thanks, I think we are on the right track. tim

 

[achris]

Re: what is this part? and what does it do?

Tim,<br /><br />Part number for the stabilizer is 87076A4. It's not cheap, $129, so I'd run with it disconnected (that's won't harm the engine) and see if the problems go away. Just disconnect the red and white wires where they attach to the power pack.<br /><br />Chris............

 

[heyitswebb]

Re: what is this part? and what does it do?

If it will run without the stabilizer then it may not be my problem. My motor will start and idle but when you give it gas it bogs down and will die. The carbs were rebuilt last year so i dont think that is the problem. someone said it may be a power pack? I found this stabilizer wire all corroded and broken. How well will it run without the stabilizer?

 

[Barnacle_Bill]

Re: what is this part? and what does it do?

Someone help here?? If you remove the stabilizer, don't your have to compensate by changing the timing?

 

[emckelvy]

Re: what is this part? and what does it do?

Remove the stabilizer, it can malfunction and advance the timing while underway, and this is a VERY bad thing to have happen on an inline! It was a 'band-aid' fix to the Inlines idling characteristics that Merc tried and it didn't work out too well. Your motor will have no ill effects from removing the stabilizer, you may have to readust your idle speed, that's all.<br /><br />You may want to check your timing anyway, it should be no more than 21 deg BTDC at cranking speeds.<br /><br />It should also be noted that ADI models further retard the timing at full throttle and it'll end up being somewhere around 18 deg BTDC.<br /><br />Re; the bogging problem, if you can't fix it by richening up the carbs' idle mixture, be sure to check the resistance of your stator. Very common on these motors to see the hi-speed windings in the stator burn out. Then the motor'll start and run on the low-speed windings, but have no power.<br /><br />HTH.....ed