[Marko]

Yes folks, my 1975 Shadow — I drive her for an hour or two; then she won’t turn over. I leave her to “cool down” for an hour or so, then she starts first go. What on earth is going on?

 

[David Watts]

Marco,
There could be a number of causes, but that's a fairly common symptom of a failing starter motor.

 

[Wraithman]

Coil or Opus, if fitted. Don't change one without doing the other.

 

[Marko]

Coil or Opus, if fitted. Don't change one without doing the other.

what do you mean by Opis?

 

[Dounraey]

Do you mean the engine will not crank on the starter motor, or it will not start.

 

[Jeff R 1]

what do you mean by Opis?

Lucus Opus ignition system inside the distributor.

 

[Marko]

when I turn the ignition key, I get nothing

 

[shadow 11]

Opus electronic ignition unit that fits in the distributor. What do you mean when you say "it won't turn over", do you mean that nothing happens when you turn the ignition key or that the starter motor turns the engine but the engine doesn't fire up. "Turn over" would appear to have different meanings depending on location

 

[shadow 11]

Sorry, missed your previous reply. OK, nothing happens when you turn the key. Sounds like a wasted battery or bad battery connections or bad starter motor connections or bad engine earth straps. If there's a battery cut-off switch that could be faulty too.

 

[AlanD]

Worn brushes?

Alan D.

 

[AlanD]

I've just remembered why I suggested worn brushes. The same thing happened to me with my ex-Silver Spirit. After I had called the AA, because they were extra busy on a holiday weekend the car sat cooling for an hour. It started Ok and I drove home. The problem was worn starter-motor brushes.

Alan D.

 

[guyslp]

I'd suspect an issue with the starter itself.

It could be worn brushes, or something else.

Without the actual chassis number it's impossible to know whether this car has the old points-type ignition versus the Lucas Opus electronic ignition, since it was introduced during the 1975 model year. The SWB cars had the Lucas Opus ignition starting with sequence number 22118 and LWB starting with sequence number 22673. But even though the Opus ignition tends to just crap out once hot, there are other symptoms, and the starter still tends to crank even if the engine will not turn over until the ignition cools down and starts working again (for a limited time). For my experience with a failing Lucas Opus ignition, see: A Christmas FTP!! . . . on the Australian forums.

 

[jake66]

When the car will not turn over on the starter motor, do all the lights work, especially headlights?
If they do then that eliminates bad connections on battery and cut off switch.

Jake

 

[eminthere]

Try checking your relays,I had the same problem and changed the starter(5hrs work) turned out it was a relay.Try crossing your solenoid with a spanner and see if it turns over?.

 

[guyslp]

Try checking your relays

And the starter relay, in particular, in this case.

 

[Marko]

The vin is LRD20890. So what ignition do I have?

 

[Wraithman]

You have a points ignition. I strongly suggest your capacitor has failed. I would replace the coil, rotor, cap, and capacitor if this has not been done in the last 5 yrs or so.
Opus ignition arrives after your chassis at 22,672

 

[Choke]

In my case, ensure wiring and connection around startemotor are clean and tight! Replace earth cable at battery to new. Often relay switches cannot get rid of their electric charge if earth cable are old. Note, electricity flowes over surface, green corroded earth cable is a sign of electrical flow handicap made worst with heat.

 

[Marko]

Many many many thanks folks for the sage advice

 

[Marko]

Ps I have looked high and low fir a capacitor for 1975 shadow but can’t find one. Am I looking it up wrong perhaps with incorrect search term? Sorry I must see completely stupid