Where do these wires go?

[lfunk11]

4.3 Mercruiser on 2005 Crownline. I think these are ground wires and I think one of them is to my Tach since it isn't working. Does the middle wire go to where the arrow is pointing? The other wire will not reach that spot so I am not sure what it is for.

 

[alldodge]

Re: Where do these wires go?

The wire that goes to your tach comes from the negative side of the coil and it is Gray. The far left one looks black and cannot let what color the other is. The item on the right is you slave relay and your boat is starting so I don't see it going there. How far back can you trace the wires?

 

[lfunk11]

Re: Where do these wires go?

The wire that goes to your tach comes from the negative side of the coil and it is Gray. The far left one looks black and cannot let what color the other is. The item on the right is you slave relay and your boat is starting so I don't see it going there. How far back can you trace the wires?

they are both black and both go into a wire bundle so not far

 

[alldodge]

Re: Where do these wires go?

they are both black and both go into a wire bundle so not far

Black wires on Mercruisers are grounds unless they come from sensors and senders at which case will not have ring terminals, they will have bullet connectors. Does it ;look like something has been removed and reinstalled (chipped paint on screw heads)?

 

[lfunk11]

Re: Where do these wires go?

Black wires on Mercruisers are grounds unless they come from sensors and senders at which case will not have ring terminals, they will have bullet connectors. Does it ;look like something has been removed and reinstalled (chipped paint on screw heads)?

not that I can tell - I thought for sure the middle one goes where the arrow is pointing. Are there any wiring diagrams? I have the original manual that came with the boat, but its not much help. I am the third owner.

 

[alldodge]

Re: Where do these wires go?

Here is the service manual for your engine
Boatinfo - Mercruiser Service Manual nr. 25 - 1998-Up - GM V6 Engines

 

[lfunk11]

Re: Where do these wires go?

Here is the service manual for your engine
Boatinfo - Mercruiser Service Manual nr. 25 - 1998-Up - GM V6 Engines

thanks for the help - i have some reading to do

 

[Bondo]

Re: Where do these wires go?

4.3 Mercruiser on 2005 Crownline. I think these are ground wires and I think one of them is to my Tach since it isn't working. Does the middle wire go to where the arrow is pointing? The other wire will not reach that spot so I am not sure what it is for.

View attachment 216527

Ayuh,.... Mercruiser builds wirin' looms for their motors, that fit Various configurations,...

Not ALL the wires are used in ALL configurations,...

Those wires have Nothin' to do with yer tach,...
Most tach problems, are Bad Tachs,...

 

[lfunk11]

Re: Where do these wires go?

Ayuh,.... Mercruiser builds wirin' looms for their motors, that fit Various configurations,...

Not ALL the wires are used in ALL configurations,...

Those wires have Nothin' to do with yer tach,...
Most tach problems, are Bad Tachs,...

thought it was odd that two wires were just left hanging there. I will investigate more to be sure. I have not explored the tach issue much yet. When I winterized the boat I was messing around back there figuring out what was what and saw those wires.

 

[achris]

Re: Where do these wires go?

thought it was odd that two wires were just left hanging there. I will investigate more to be sure. I have not explored the tach issue much yet. When I winterized the boat I was messing around back there figuring out what was what and saw those wires.

Not unusual... Have a look at most cars these days. The same wiring harness goes into all models of that vehicle, but not all the options are installed, so there are plenty of empty plugs just laying around....

Chris....

 

[Fun Times]

Re: Where do these wires go?

One of the black wires would have gone to your Mercathode anti-corrosion system (blue box) had your engine model come with one from new.

The other one is not used and just sits idle like it is. Neither one will affect your tachometer in any way by not being hooked up.

For a basic check of your tachometer, you may want to locate the black 10 pin cannon plug wire harness on the engine and try wiggling it around with the engine running to see if you get your tachometer working once again.

Also try tapping on the gauge itself.

On the back of the tachometer gauge, there may be a switch with some numbers and maybe an arrow pointing to the numbers. Try turning the switch back and forth a few times and landing on the number needed for your engine size.

Also if the mounting nuts to the gauge are to tight, that could make the gauge get stuck as well but that is rare.

Let us know what you find, good luck.

 

[lfunk11]

Re: Where do these wires go?

One of the black wires would have gone to your Mercathode anti-corrosion system (blue box) had your engine model come with one from new.

The other one is not used and just sits idle like it is. Neither one will affect your tachometer in any way by not being hooked up.

For a basic check of your tachometer, you may want to locate the black 10 pin cannon plug wire harness on the engine and try wiggling it around with the engine running to see if you get your tachometer working once again.

Also try tapping on the gauge itself.

On the back of the tachometer gauge, there may be a switch with some numbers and maybe an arrow pointing to the numbers. Try turning the switch back and forth a few times and landing on the number needed for your engine size.

Also if the mounting nuts to the gauge are to tight, that could make the gauge get stuck as well but that is rare.

Let us know what you find, good luck.

thanks! I am busy getting the boat clean since the PO wasn't all that clean. Then I will start knocking things off on the checklist, but this will be a good starting point once I have a night to look at the tach.