Ignition light / control box

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Andyhereford
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Ignition light / control box

Post by Andyhereford »

My car is not yet on the road but every few weeks I am in the habit of starting the engine and letting it run for a while.The last couple of times that I have done this when I turn the key the ignition / oil pressure lights come on as normal and the pump starts clicking but before the key has been fully turned to start the engine both lights have gone off and on turning the key further nothing happens, as if the battery is flat. The battery is not flat. Today, having had the same problem, and for no particular reason , I took the cover off the control box and gently tapped it with a bit of wood. Turned the key and it started first time. Was this luck or does it indicate a fault in the control box. The car has always previously started very well. The only thing that I have recently done is to fit a new petrol pump. This appears to be working well and when the car starts it runs quite smoothly.
The control box appears to be original ( 68 four door) so I would imagine that it is time perhaps to fit a new one.
Any advice please.
myoldjalopy
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Re: Ignition light / control box

Post by myoldjalopy »

If the battery is fully charged then I can't see how a fault in the control box would prevent the starter motor turning over when you try. More likely a poor connection/fault at the ignition switch or associated wiring, or even at the battery terminals/solenoid. I wouldn't rush to get a new control box until you have found the fault, as the new ones are not good quality compared to the old ones.
pgp001
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Re: Ignition light / control box

Post by pgp001 »

It does have all the hallmarks of a poor connection to the battery, or a bad earth connection.

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Mark Wilson
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Re: Ignition light / control box

Post by Mark Wilson »

I mentioned a couple of days ago that my solenoid had failed. When the new replacement (which I already had) "failed" as well I investigated a bit further and found that the earthing of the solenoid body was the problem. Scraping a bit of paint from the bulkhead behind the solenoid, cleaning the fixing screws and applying a blob of dielectric grease has resulted in both solenoids working fine. (I've gone back to the old red button one for convenience). Quite surprising how critical this earth connection is - before cleaning it I could get the solenoid to clunk quite loudly without making the starter motor circuit connection. It does sound very much as though this could be your problem.
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geoberni
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Re: Ignition light / control box

Post by geoberni »

Control Box is certainly nothing to do with whether the engine turns over or not.
The Control Box is all about controlling the charging circuit, nothing to do with the actual turning the engine over on the starter.
Sounds like a poor earth or loose connection.

I would just ask that you confirm its a standard engine and starter arrangement, and not some hybrid affair someone has installed....?
Basil the 1955 series II

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Andyhereford
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Re: Ignition light / control box

Post by Andyhereford »

Thanks for all your help / advice as always. It is a completely standard engine. The only thing that I have changed is to replace the original fuel pump. In doing this I had to reposition one of the earth wires. My intention is to start here and make sure that this is a good connection. I will then work my way through the various suggestions above. It was all working fine until I replaced the pump...the old one aim was leaking fuel....so I expect that it is something to do with that. I have not done anything else to the engine apart from change the plugs and the oil. Anyway. Thanks again for everybody’s help and advice.
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