faulty solenoid?

[mckellen]

I have a 65 4A with -ve earth, electronic ignition and ...no signs of life. There is 12.4V across the battery terminals, the ignition light lights up ...and dims when I turn the key, otherwise nothing. I suspect the starter solenoid (or the ignition switch?) or connections thereto. Where do I go from here? Is it possible to test the solenoid on the car?

 

Any help or suggestions greatly appreciated.

 

Regards,

 

Phil

[TR 2100]

I have a 65 4A with -ve earth, electronic ignition and ...no signs of life.

There is 12.4V across the battery terminals, the ignition light lights up ...

and dims when I turn the key, otherwise nothing. I suspect the starter

solenoid (or the ignition switch?) or connections thereto.

Where do I go from here? Is it possible to test the solenoid on the car?

 

Hi Phil,

 

Lots of things it could be - I'm sure you'll get lots of suggestions.

Maybe you'll end up taking so many things to bits that you'll end

up with a restoration on your hands!

 

Something you should check is that you have a good earth - not just

the battery earth but the earth strap fitted from engine to chassis.

This is a bit difficult to get at, but it's on the nearside front suspension

by the engine mounting. Remove, wire brush and refit.

 

I assume the battery is well charged.

 

AlanR

[Smokey]

You can check the solenoid by running a wire from the positive terminal of the battery to the terminal on your solenoid connected to your ignition switch. You can confirm that via the wiring diagram, but it would be a thin wire - not the main power wires to the battery and starter. I don't have a wiring diagram in front of me, but others may be able to help on that. I have long wires with insulated alligator clips for these experiments - very handy.

[Richard V]

Hi,

 

First think I notice with your problem is that 12.4 volts seems a bit low. A normal healthy battery should give about 14v across the terminaly with no load and down to 12v under full starting load.

 

Get a helper to switch on the lights or try the starter whilst you hold the tester across the battery, I bet you it drops to about 9v.

 

Do a comparison check on a mates car or your "every day" car. If confirmed change the battery. If this is the case, either the cold weather has killed of an aging battery or your charging system is shot...then the fun starts!

 

As Alan said, this is only one of many solutions, as Im sure you will get many.

 

Oh, and welcome to the forum

 

Cheers,

 

Richard.

Edited April 14, 2009 by Richard V

[Steve Brabazon]

The wire should be the white/red one.

 

Steve

 

TR4 LHD to RHD

[BrianC]

There are lots of posts already on this subject, including one of mine (search all forums for 'solenoid').

However, assuming all connections are clean and tight, unless it's fairly new, I would consider the battery as number 1 suspect (it was in my case).

If you don't have a spare, good battery handy, try using jump leads or a battery jump-start pack. If it starts, then you need a new battery - an old battery may not have enough energy to turn the motor (especially the original type) and still supply enough power to the coil to generate a spark.

Edited April 14, 2009 by BrianC

[paul gardner]

For a lead acid battery to be fully charged, it should show 12.7 volts at normal average uk temps. If it shows 12.4 volts, it is only 75 per cent charged. I suspect this may be the root of your starting problem.

Yours

Paul

[Smokey]

When in doubt, I always charge the battery .

[BrianC]

In my experience, you can't always rely on the battery voltage, as when subjected to a heavy load, if there is any internal fault such as collapsing plates, then a short circuit can occur and you don't get the full whack.

[mckellen]

Guys,

 

Apologies for not coming back sooner, swamped with work this week! Lots of great advice, I 'll try and have a go at it over the weekend, and let you know how I get on.

 

Many thanks,

 

Phil

[Tony Millward]

Thought this may be of some help as it contains a lot of useful battery info....

 

regards all

 

Tony

Battery_FAQ.pdf

Battery_FAQ.pdf

[Richard V]

Hi,

 

A normal healthy battery should give about 14v across the terminaly with no load and down to 12v under full starting load.

 

Sorry for my obvious error..... Should read "14v across the terminals with the engine running", and yes down to no lower than 12v whilst starting.

 

Will try to pay more attention

 

Cheers,

 

Richard.

[mckellen]

Where to start? The car has finally started, so thank you all for your ideas and assistance.

 

You were all sooo close, but the cigar ultimately goes to my father for this gem "it [the solenoid] is probably stuck, have you tried a hammer?". A couple of gentle prods and a sharp whack with the wooden handle of an old hammer and ...she turned over.

 

OK, so I had to jump start her off the Volvo, and yes, I need a new battery, but you all knew that already...

 

I have learned a lot this week...

 

... there is apparently something called "ghost voltage" or why a 12V battery can have 14V in it, and why it's "flat" even with 12.4V

 

... not to trace electrical circuits with a finger placed on each component whilst you ponder it's function, at least not while the wife is sitting in the car. To be fair, she "thought it might start that time".

 

... and that dad's brain has not yet turned entirely to mush, so the care home and my plans for a cruise will have to go on hold for a while

 

Thanks again.

 

Phil

[BrianC]

You were all sooo close, but the cigar ultimately goes to my father for this gem "it [the solenoid] is probably stuck, have you tried a hammer?". A couple of gentle prods and a sharp whack with the wooden handle of an old hammer and ...she turned over.

Doh! Should have thought of this - I had the same thing happen on one of my first cars (probably the Standard 10) long, long ago. Glad you've got it sorted and interesting to see how just solving a simple problem can reveal a number of other minor issues.