Starter motor - what connections are what?

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Cataldoodledoo
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Starter motor - what connections are what?

Post by Cataldoodledoo »

Hi everyone,

Can you confirm what is what please.

Top bolt - battery/mains power supply?
Two spade connectors on right - solenoid trigger?
Bottom bolt - ?

Also looking to earth close by. Any suggestions?

Thanks.

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Early 1985 VW T25 1.9 Watercooled

davidoft1
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Re: Starter motor - what connections are what?

Post by davidoft1 »

The solenoid is a switch , it connects the live at the top to the lower connection which is the live to the motor part

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maxstu
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Re: Starter motor - what connections are what?

Post by maxstu »

Cataldoodledoo wrote: 10 Apr 2021, 19:41 Hi everyone,

Can you confirm what is what please.

Top bolt - battery/mains power supply?
Two spade connectors on right - solenoid trigger?
Bottom bolt - ?

Also looking to earth close by. Any suggestions?

Thanks.

Image

Bottom bolt serves as a connection point for the braided cable from from solenoid switch to starter. Earth is through starter body against mounting point on engine casing.
It all looks a bit cruddy. Take starter off and give it a good clean up. Including the engine casing and face of starter.
MaxStu
1989 DJ 2.1 Auto Leisuredrive rusty bucket.
"Blissfully happy in your presence".

Stesaw
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Re: Starter motor - what connections are what?

Post by Stesaw »

Earth strap from gearbox bolts at the front where it bolts to the chassis 
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

Cataldoodledoo
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Re: Starter motor - what connections are what?

Post by Cataldoodledoo »

Thanks everyone. Cleaning it up and wiring in a hard start relay so it’s extra reliable. 

I’ve drilled/screwed in a new earth and then the relay into the chassis above the starter motor. Will post a picture shortly!
Early 1985 VW T25 1.9 Watercooled

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Re: Starter motor - what connections are what?

Post by Stesaw »

Image
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

Cataldoodledoo
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Re: Starter motor - what connections are what?

Post by Cataldoodledoo »

Shiny!
Early 1985 VW T25 1.9 Watercooled

Cataldoodledoo
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Re: Starter motor - what connections are what?

Post by Cataldoodledoo »

I’ve just added this.

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Early 1985 VW T25 1.9 Watercooled

Stesaw
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Re: Starter motor - what connections are what?

Post by Stesaw »

That's not my van, just an example of the size of ground cable you need and where to generally put it.
1985 LeisureDrive 2.1DJ 5 Speed syncro conversion project.
1979 LT 2.0CH Westy project

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Robsey
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Re: Starter motor - what connections are what?

Post by Robsey »

The general rule that I use for connecting up any kind of relay is.

That the wires for terminals
86 - control wire,
And
85 - earth terminal,
Should both be large enough to safely operate the relay. This depends on the power consumption of the relay itself.

Terminal 30 - supply wire
And
Terminal 67 - output wire to the load.
Should be large enough to safely operate the load dependent upon the power consumption of the load.
Taking into account, that any coil type device (solenoid, motor etc) will have a bit of a spike or surge to get any moving parts to move.

So looking at that.
Terminal 86 - original red / black wire is 6mm.

Terminal 85 - in my mind, anything above 1mm brown wire should work.

Terminal 30 - 6mm red wire from main starter motor connector.

Terminal 87 - 6mm red (red / black) wire to solenoid connection.
1983 Tin Top with a poorly DF and 4 speed DT box.
1987 Electrics and a DJ engine.
Maybe one day I might get it finished

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Re: Starter motor - what connections are what?

Post by Cataldoodledoo »

Robsey wrote:The general rule that I use for connecting up any kind of relay is.

That the wires for terminals
86 - control wire,
And
85 - earth terminal,
Should both be large enough to safely operate the relay. This depends on the power consumption of the relay itself.

Terminal 30 - supply wire
And
Terminal 67 - output wire to the load.
Should be large enough to safely operate the load dependent upon the power consumption of the load.
Taking into account, that any coil type device (solenoid, motor etc) will have a bit of a spike or surge to get any moving parts to move.

So looking at that.
Terminal 86 - original red / black wire is 6mm.

Terminal 85 - in my mind, anything above 1mm brown wire should work.

Terminal 30 - 6mm red wire from main starter motor connector.

Terminal 87 - 6mm red (red / black) wire to solenoid connection.
That’s really helpful! Thanks so much.


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Early 1985 VW T25 1.9 Watercooled

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Robsey
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Re: Starter motor - what connections are what?

Post by Robsey »

You are most welcome.

I do find from time to time, that many manufacturers - including VW will reverse the wires compared to how I have listed them

That is
Pins 86 and 85.
I have seen either one used as the ground pin.
With the other being the "trigger" or control wire.
Back in my early days, it was considered the norm to use pin 85 for earth / ground.

As for pins 30 and 87.
These can indeed be wired either way round.
It will not make any difference.

For clarification, on pin 87, I put the red/black wire in brackets, for those who wish to have the "correct" coloured wire on the solenoid connector bolt.
In truth, any colour could be used, to differentiate it from the red direct battery feed.
1983 Tin Top with a poorly DF and 4 speed DT box.
1987 Electrics and a DJ engine.
Maybe one day I might get it finished

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bigherb
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Re: Starter motor - what connections are what?

Post by bigherb »

Cataldoodledoo wrote: 10 Apr 2021, 22:03 I’ve just added this.

Image
Don't mount the relay underneath, or you will eventually be back to square one, there is enough cable to mount the relay out of the weather in the engine bay.

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Robsey
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Re: Starter motor - what connections are what?

Post by Robsey »

Good call...

Mounting a relay underneath the van in an exposed area is simply begging for road spray etc to be thrown at it.

Ideally it could be put in a spare relay / junction box to protect it from ambient muck, moisture and changes in engine bay temperature.

It all depends how belt and braces you want to go.

A second consideration.
If the relay or fuse blows... I would rather grope around in the engine bay, than having to climb back under the van.

After having a second look at the underside photo...
that ground tag for the relay is screwed to a rusty part.
So that connection will not take long to rust too.
1983 Tin Top with a poorly DF and 4 speed DT box.
1987 Electrics and a DJ engine.
Maybe one day I might get it finished

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