Starter motor plastic cover removal

[Charles Farran]

Hi Michael,
Thanks for the clarification. I agree that it is a way of resolving the issue if Dave doesn't want to have the hassle of accessing the solenoid again beneath the car & the rubber boot.
Dave you need to insulate the original W/ LG coming back from the solenoid if it is still attached at that end to prevent a possible sbort when cranking the engine if you follow Michael's suggested solution.
Cheers,
Charles

[Dave Wheatley]

Finally got the car up and running on 12v coil. After another dud condenser and poor earthing of the battery negative.
Just now I am taking the 12v to the coil from the w1 terminal on the ignition relay, and the car runs fine.
I am wanting to include Michael Barclay's 5 pin relay.
Michael's relay shows a pin 87b. All the 5 pin relays that I have found have the extra pin as 87a. Is this significant?

[Paul Scott]

87a is different Dave.

That relay switches the circuit from one output 87a to the output 87

Unpowered power passes from 30 to 87a
But when energised 30 to 87

Mikes is a double throw

Umpowere 30 goes no where
Powered 30 goes to both 87 & 87B

Regards
Paul

[Paul Scott]

Https://www.12voltplanet.co.uk/relay-guide.html

Paul

[Dave Wheatley]

Thanks for that Paul. Very interesting link which I have bookmarked.
My car electrics knowledge is NIL.
I've found a double throw relay with 87b terminal, but, I can't see the point of the double throw for the application under discussion. Why can't a simple piggyback connector on to 87 on the original starter relay work just as well?
But look, even if you explain it, I won't understand it, so let's leave it that the double throw is what I need otherwise I will be going round in circles.

[Charles Farran]

Dave,
If you think of a wire being a pipe , water can flow in either direction depending on which end you pour water in (ignoring gravity)!
As you end up with 2 feeds piggy backed at the + LT side of the coil, when the engine is running, a current (in my analogy water) will flow from the ignition relay feed to the coil & then out again down the feed to the starter relay where ,if you have a piggyback connector on 87 that in turn will send a current to the starter solenoid on the back of the starter motor. (You need a "dam" to stop the water flow in either direction)! Hence Michael's suggested solution!
Hope I've helped rather than hindered. (Incidentally a diode is in reality a one directional dam, that allows current to flow only one way provided the pressure isn't too great the other way........................)!
Cheers,
Charles

[Paul Scott]

Dave,

The extra feed for the relay is really only required if you are using a ballasted system. This is because it needs 12V to improve the spark when cranking.

If you are no longer using the ballast in the loom you need to make sure it is disconnected at both ends. Isolated so it cannot touch the body work or engine or it will cause a short especially when cranking if the 12v coil lead from the starter is still connected to the coil.

I have on my 75 disconnected both ends of the ballast from inside the loom and added a separate ballast resistor. But I have left the original so I can reconnect if required or I can bypass and fit a 12v coil if I had to. I don't believe I had a problem with the original ballast, but as I was trying to fix an intermittent fault I left as it was after everything became good. I believe the main issue was my condenser - after trialling a few diagnostic warning lights to locate the issue. Replaced points with powerspark electronic module.

StaySafe

Paul

[Dave Wheatley]

This is what I have done so far.
Piggy backed 12v to coil wire onto ignition relay terminal W1 (85).
Split and insulated the 2 conjoined old green/white wires that were originally connected to the +coil.
Everything is working.
I've ordered the special relay with 87b terminal, but not sure if I will use it.

[Michael Barclay]

Hi Dave
Hear is a link to the relay you need if you wish to go with my suggestion.
https://www.autoelectricsupplies.co.uk/ ... ategory/36
To fit, simply replace this relay with the current ignition relay using the picture/pin Nos on top of the relay as a guide.
Pin 85 – Black
Pin 86 White/Red
Pin 30 Brown
Pin 87 White /Brown

Then remove the White/ LG wire from the starter motor and insulate as per Paul’s suggestion.
You have already separated the 2 White/LG wires on the coil. Identify which one goes to the starter solenoid and insulate. The other White /LG wire is from the Ballast resistor. Reconnect this to the coil.
With the ignition turned on check you have between 6 and 9 volts between the coil and ground. If OK turn off the ignition.
Now run a new wire (Preferably White /LG to keep everything correct)) from the coil to terminal 87 B on the new relay.
Your car should then start as per the original factory set up with full battery voltage to the coil under cranking.
If you were closer to me I would offer to assist but Scotland is a bit of a trek from Abingdon.
Hop this helps.
Mike Barclay

[Michael Barclay]

Just for reference
Attached is a picture of the pink ballast resistor wire where it terminates and goes back to the coil as a White/LG wire.
For orientation picture is taken facing the engine compartment . The wire is down on the right hand side of the radiator.
Best regards
Mike Barclay