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David Lacey
Experienced User
Username: dlacey

Post Number: 76
Registered: 11-2010
Posted on Wednesday, 05 April, 2023 - 18:12:   Edit PostDelete PostView Post/Check IP

Hey All,
I have been away 5 years or so but have now resurrected my '68 Shadow (SRH4452) as my daily driver here in Penang, Malaysia.
I have an issue with the start circuit: When cold (28 C here) the starter key switch on dash doesn't seem to power the solenoid.. this isn't a weak battery or dodgy starter issue, its that the solenoid isn't actuating (It starts fine if i press the solenoid button). Once warmed-up the car starts on the key, via the solenoid, every time.
i have dismantled and cleaned the starter switch in the dash centre with no effect on the problem. As far as I can see from the wiring diags, theres no starter relay between the dash start switch and the solenoid - is that correct?
I believe there is some transmission interlock to prevent starting in drive/reverse (this is a 4sp hydramatic car)...could it be that the interlock is intermittent?

Does anyone know where these interlock switches are physically located? In the steering column? or down by the gearbox?

or - could it be that my solenoid coil is open circuit when cold??

thanks for any ideas or suggestions,
dave
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 3326
Registered: 06-2009
Posted on Thursday, 06 April, 2023 - 00:42:   Edit PostDelete PostView Post/Check IP

Have you tried shifting out of and back into Park when this occurs?

I can't honestly recall whether there was an interlock in place as early as 1968, but there was later, and there is a microswitch related to same in the shifter on the steering column. If yours has this, too, it might "get sticky" when the temperature drops and might, perhaps, respond to a shift out and back to park to loosen it up.

But, to be honest, I doubt it has anything strictly to do with temperature, as 28 degrees C is still mighty warm with regard to temperature related stickiness.

Brian
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David Lacey
Experienced User
Username: dlacey

Post Number: 77
Registered: 11-2010
Posted on Thursday, 06 April, 2023 - 07:56:   Edit PostDelete PostView Post/Check IP

Hi Brian,

Yes, i have tried cycling the gear selector around but it doesnt seem to help..If i turn the ignition key to start 10-20 times then it will finally actuate the solenoid and the car starts-up nicely. agree that the temperatures I am talking about are already high... and the cabin temperature stays at this 28C or cools slightly due to AC. Only something in the engine bay or on the gearbox will see a significant temperature swing from ~30 to ~70C i guess.. It may not be temperature related...but it most definitely is first-start-of-the-day related,
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Robert J. Sprauer
Frequent User
Username: wraithman

Post Number: 825
Registered: 11-2017
Posted on Thursday, 06 April, 2023 - 11:06:   Edit PostDelete PostView Post/Check IP

I would remove the starter relay after recording the connections. Open the relay and clean the relay contacts. They may also have to be adjusted so they land square. Disconnect battery before doing so.
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Omar M. Shams
Grand Master
Username: omar

Post Number: 2203
Registered: 04-2009
Posted on Thursday, 06 April, 2023 - 18:01:   Edit PostDelete PostView Post/Check IP

My suspicions lie with the ignition switch.
Before removing the starter relay, I would simulate a direct signal to it (as if the ignition switch is activated). The car should start every time with such a signal. If that was the case then the switch itself will have worn or poor contacts.

A reply to previous messages: Yes this car will have starter inhibits given that the Clouds before them had these.
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David Lacey
Experienced User
Username: dlacey

Post Number: 78
Registered: 11-2010
Posted on Friday, 07 April, 2023 - 12:41:   Edit PostDelete PostView Post/Check IP

Hi Omar,
I pulled the 'switch barrel' out of the dash and found that the starter switch is not some plastic encapsulated lump, but fully open and serviceable...the contacts were dirty and i cleaned with a cotton bud.. afterwards the switch tested repeatedly good with an ohmmeter (it also tested good before clean..).
Next action i will test volts on the Lucas 2ST solenoid...which is, in effect, the starter relay on these early shadows (actual starter solenoid is down on the starter with the heavy gauge cable from teh battery)
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Omar M. Shams
Grand Master
Username: omar

Post Number: 2205
Registered: 04-2009
Posted on Saturday, 08 April, 2023 - 06:19:   Edit PostDelete PostView Post/Check IP

I think you are on the right track David.
Good luck.
Omar
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 2558
Registered: 09-2004
Posted on Saturday, 08 April, 2023 - 17:21:   Edit PostDelete PostView Post/Check IP

After trying to find my post on a very similar failings when this posting started and having no luck!

So I will start with the car being cold and not used for some time.
Turning the key to start all lights illuminated but car would not always start ie starter motor would not turn, check battery and a few more attempts and listening and hearing the solenoid operation it would fire up and be ok for the rest of the day.
This was a common occurrence until I found the problem ie main battery connection (corrosion) to starter solenoid.
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David Lacey
Experienced User
Username: dlacey

Post Number: 79
Registered: 11-2010
Posted on Tuesday, 11 April, 2023 - 15:38:   Edit PostDelete PostView Post/Check IP

Hey All,
Well my starting problem gets more intermittent (happens less often) as I exercise the car after its 5 year slumber.
I dug in to the electrical diagrams and this confirms that, yes, there is an interlock...it's called the "Neutral Start Switch" and it switches the earth side of the Lucas 2ST solenoid/relay.
However, even more disconcerting...I found that my car will happily start with either 'R' or '4' selected...so this Neutral Switch is either not present or not functioning.
I will keep digging...

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