Volvo MD11c What do these wire do

thesaintlyone

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OKi bit of a tricky one here need to replace the positive and negative cables that run to my Volvo MD11c. I am going to go with 35mm2 Cables from the battery switch to both positive and negative. Today I undid a screw where the Negative cable is connected to the engine and there were three other cables attached to the same screw they were not connected at the other end and am wondering if anyone knows what they might be in relation to I am currently redoing the electrics. I will have someone who knows this stuff Connect up the engine correctly as whilst I understand my house and start Battery connections the ignition is beyond me. And I'm really just asking to know whether I need to purchase new versions of these cables beforehand.
 
OKi bit of a tricky one here need to replace the positive and negative cables that run to my Volvo MD11c. I am going to go with 35mm2 Cables from the battery switch to both positive and negative. Today I undid a screw where the Negative cable is connected to the engine and there were three other cables attached to the same screw they were not connected at the other end and am wondering if anyone knows what they might be in relation to I am currently redoing the electrics. I will have someone who knows this stuff Connect up the engine correctly as whilst I understand my house and start Battery connections the ignition is beyond me. And I'm really just asking to know whether I need to purchase new versions of these cables beforehand.

It is difficult to say if they are not connected to anything. Where about do they lead. Do the positions of the other ends give any clue. Where do they go, how thick are they?

Bonding wires for anodes or the earth of an old shorepower system?. Connections for equipment removed?

The wiring diagram is in the owners manual but gives no clues.
It shows 35mm² cables for the main positive and negative.

MD11C wiring.JPG

BTW diesel engines do not have ignition stystems.
 
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By ignition system, you presumably mean the switch panel? Unless you know electrics these can be a bit of a mystery, but the rule of thumb with Volvo is to conect like with like.I.e red to red, yellow to yellow etc. As VicS says, your spare wires are probably part of a former anode earthing system. However if they are not connected to anything and everything works it can be ignored. Just make sure they have not disconnected themselves from something nearby, usually above, or haven't dropped down from where they should be connected. It should be fairly obvious if they have broken or come unscrewed
 
Thinking about it. Could be the wires for the Sacrificial Annode how are they usually wired in.

Sacrificial anodes must be reasonably close to , "able to see" what they are protecting and wired, with a good low resistance connection, to it,

It is common for a hull anode fitted to protect a shaft driven prop to be connected to the engine block although any flexible shaft coupling must be bridged to complete the circuit.
 
I am going to go with 35mm2 Cables from the battery switch to both positive and negative.

there were three other cables attached to the same screw they were not connected at the other end and am wondering if anyone knows what they might be

Might be misreading the first bit, but you are not taking battery negative to the battery switch, are you?

Regarding the three cables on the engine block, one might possibly be a direct connection to the alternator negative post, if fairly beefy...
 
Might be misreading the first bit, but you are not taking battery negative to the battery switch, are you?

Regarding the three cables on the engine block, one might possibly be a direct connection to the alternator negative post, if fairly beefy...

You could be right. If it is then it should be 4mm² and blue. I forget where it is connected to the block.
 
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