Volvo 2020 engine wiring

[Freda class]

The Volvo 2020 engine on my boat has been out for servicing whilst new bearers and engine mounts were fitted and now I need to reconnect the wiring.

Help!

Unfortunately the engineer who took the engine out can't remember what goes where and I took no photos for guidance - very silly I know.
I've posted two pics of the engine and the 4 connections that need to be made.

Pic 1 is the rear of the alternator. The connector at top right is B- and that at bottom right is B+
Both of these have loose nuts so there was something connected here.



Pic 2 is a side view of the engine with the alternator at left.
I'm assuming the starter solenoid is the unit at bottom right with the large hex assembly and a loose nut on it so something attaches here.







And finally, the unit at mid-centre with the shiny nut - what connects here?

Very grateful for any help.

 

[VicS]

There are wiring diagrams in (some of ) the owners manuals.

If yours does not have a wiring diagram have a look at one or two others for the MD 2010/20 etc range which can be downloaded from http://www.volvopenta.com/volvopent...lication_search/pages/publication_search.aspx

direct link to a manual with a wiring diagram which applies http://vppneuapps.volvo.com/ww/PIE/...T403&d=Owners Publication&s=476674&lang=en-GB
See page 17

You should have no problem sorting out the connections to B+ and B-. B+ is the main + output ( red wire). B- is the the negative ( two black wires).


The starter solenoid is the item on top of the starter motor and more or less part of it. ... The part with the shiny nut you refer to. That'll be the place the main (starter) battery + connection goes, along with several others. (The connection from alternator B+ and two smaller red wires.) Terminal 30 in the diagrams.

The item below the starter motor is the "earthing relay"


Engineer did you call him ??? Not what I'd call him. Wiring diagrams are all in the workshop manuals which he should have avaialble!


There are some wiring diagrams in the manuals on Bluemoment.com but they are not all copied completely ... Worth a look though if you cannot find what you want on the VP site.

See http://www.bluemoment.com/manuals/Volvo_Penta_MD2010-20-30-40.pdf

There is a diagram in there (page 80) that answers your questions I think

 

[cryan]

Engineers can have as much dificulty getting hold of manuals as anyone else. If your not an agent for a brand it can be hit and miss. Some manufacturers are great and send you everything, some are not good at all. However he should have taken a photo or drawn a sketch in his notepad.
As stated on Alternator:
B+ is the positive lead from Alt to Batteries
B- is the Negative lead
If there is a W post that will be for your tacho pickup
The other of the four might be a dc output to your volt meter.

For the starter:
The big connection on the back should be the positive power lead. This will be a heavy guage cable
There should also be a smaller connection on the solenoid which will take a 30amp (ish) positive feed from the ignition key/starter button.
The starter may return its negative power through the casing to earth or it might have a negative cable attached to either the starter motor or its hold down bolts holding to the engine.
Once you get it sorted take digital photos, label the connections on a computer then print off and laminate them so you always have a copy onboard.

 

[Plevier]

That does not look the same as my 2020D. Is it an early 2020A which is totally isolated instead of being insulated from the gearbox like later ones? I suspect the unit at the bottom right, which I don't have, might be the negative isolation relay. The starter solenoid is the one "at mid centre with the shiny nut."
If you don't have the manual you can get it from VP website.

B- on the alternator goes directly to battery -ve isolator switch on mine, suspect on yours it will go to the relay mentioned above, which will then connect to the isolator switch.
B+ goes to battery +ve isolator switch.

Edit - 2020A manual at http://vppneuapps.volvo.com/ww/PIE/...T403&d=Owners Publication&s=476674&lang=en-GB confirms it's the earthing relay.

Wiring diagram on P17 should sort you out.

 

[Freda class]

Ok, thanks for that.
The wiring diagram that the engineer has doesn't show the earthing relay hence some confusion!
I'll have a go with your information and may well come back for clarification!!!
Regards
Richard

 

[VicS]

Ok, thanks for that.
The wiring diagram that the engineer has doesn't show the earthing relay hence some confusion!
I'll have a go with your information and may well come back for clarification!!!
Regards
Richard

AsTroubadour pointed out the earthing relay was only fitted to earlier versions, just the earliest I think.

The links I have added to my earlier post / given by Troubadour should enable you to sort it out.

But download yourself a copy of the owners manual.. presumably you don't have one