4.3L Mercruiser 1998-Unknown Wire

[fd232]

I have a 1998 4.3L Mercruiser with a Alpha 1 drive unit. The engine has the Thunderbolt ignition. I changed the distributor cap/rotor and when I was finished, I noticed a black wire that was hanging (unconnected). I am almost certain the wire was not attached before I changed the cap, and the connector appears to never have been attached because it has no signs of being tightened and has a slight whitish corrosion.

My question is does this wire need attached to one of the distributor cap mounting screws, it looks like it should be, but I'm not sure. Hopefully someone can look at this picture and has a 4.3L just like mine and can look at their distributor cap to see if this ground wire (I assume a ground wire!!??) is attached. I cannot follow the black wire because it enters a wire wad that is wrapped.

You can see the hanging wire very close to the distributor cap (on the left).

Thanks for the help!!

 

[HT32BSX115]

Re: 4.3L Mercruiser 1998-Unknown Wire

Howdy,

Black is usually always ground.

Are you absolutely sure it's black?


You might want to refer to a Mercury service manual.

 

[JustJason]

Re: 4.3L Mercruiser 1998-Unknown Wire

probably a ground wire for the ignition module under the cap.....
the reason why its running is coz the module is pulling ground through the distributor.....
i'd hook the wire back up though

 

[neilmw]

Re: 4.3L Mercruiser 1998-Unknown Wire

i have 2 blacks coming from the dist' both grounded at the ex'elbow

 

[Don S]

Re: 4.3L Mercruiser 1998-Unknown Wire

Best thing to do is check it with an ohm meter. One lead on the wire the other to a good ground. IF you have continuity, the other end is already hooked up to a ground and the wire is a ground wire already in the harness for use with an item your engine doesn't have.

 

[mike456]

Re: 4.3L Mercruiser 1998-Unknown Wire

my 1992 5.7L has the same wire. I believe it is there to be used during a tune up. Somehow you use it to ground the ignition when setting the timing. If it was not connected previously and the engines runs fine without it then don't worry about it. I'm sure Don S could give you the full details on it.

 

[J JACKSON]

Re: 4.3L Mercruiser 1998-Unknown Wire

my 1996 4.3 has the same wire beside the distributor i was wondering what it was for