Disconnected wiring

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MDP
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Disconnected wiring

Postby MDP » Thu Dec 31, 2020 2:09 pm

I am trying to get my recently purchased Traveller running and there are 3 wires hanging down in the engine bay (low down left hand corner of the picture circled - blue connector and 2 uncovered connectors to the right, above the steering column) that look like they were connected to something. I'm not sure what or whether this would have anything to do with it not starting. It looks like there was an alarm system at some point as there is an alarm trigger switch on the bonnet, but 2 of these wires look to be part of the original loom. Having looked at pictures of other engine bays I can't see anything fitted in this area. Does anyone know what they could be for?
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les
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Re: Disconnected wiring

Postby les » Thu Dec 31, 2020 2:25 pm

I think it would be an impossible task, to identify without being there, considering the amount of wiring circulating around and there seems to be a lot of gadgets there too. I’d be inclined to disconnect all the ‘extras’ and with the help of the wiring diagram start fresh under the bonnet. If you have a meter, it might come in handy.


Sleeper
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Re: Disconnected wiring

Postby Sleeper » Thu Dec 31, 2020 3:05 pm

Hard to tell , " 2 of these wires look to be part of the original loom. " but they all look like they're not part of the loom?

John ;-)

geoberni
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Re: Disconnected wiring

Postby geoberni » Thu Dec 31, 2020 3:24 pm

:o
Quite honestly....
A) I don't think they are anything to do with 'original' wiring, Spade Connections are pretty rare beast on standard wiring and there's nothing to connect them to that I can see. In fact most if not all of the cats cradle that I've ringed RED looks like additional wiring. It's not going into the main loom.
B) Why is there a Horn where it can rub on the bonnet rod?
It already looks as though there's a siren for the Alarm system?
C) What on earth is that I've ringed in Yellow? it looks like a Starter Cable connection to a solenoid or something....Perhaps a battery isolator switch fitted through the bulkhead?
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MDP wrote:
Thu Dec 31, 2020 2:09 pm
I'm not sure what or whether this would have anything to do with it not starting.
The starting circuit is quite small and there's been ample chat about Starting problems recently.
When you say 'not starting' what do you mean?
No turning over at all?
No signs of it sparking and trying to fire up?

Quite frankly, with that mess under the bonnet I wouldn't even be connecting the battery for fear of something catching fire!
Like Les said, get a multimeter so you can do some continuity checks on tracing wiring. Don't listen to anyone suggesting using a 'test lamp' because you don't know if it's safe to actually connect the battery. :roll:

Edit: I've just noticed the Pull Start, so its an early model, and that must be an isolator switch added to it.... :roll:
Basil the 1955 series II

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JOWETTJAVELIN
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Re: Disconnected wiring

Postby JOWETTJAVELIN » Thu Dec 31, 2020 6:06 pm

Oh dear. You just won't let things go.

MDP, isolating the bare terminals you circled with some insulating tape around them would be a priority. Then in the long run a new wiring loom, as this one looks past it. It is certainly an interesting vehicle with these modifications, and all that angle-iron is pretty heavy duty.
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kevin s
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Re: Disconnected wiring

Postby kevin s » Thu Dec 31, 2020 10:41 pm

I usually rip all the non standard wiring out get the standard set up correct and working then make any changes I require.

If you just want to get it running you could disconnect all the original wiring it only needs a live feed to the coil and fuel pump to run.

oliver90owner
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Re: Disconnected wiring

Postby oliver90owner » Thu Dec 31, 2020 10:52 pm

It would appear that these wires may well have some connection to the security bits added by a previous owner - I note the switch and bracket, which presumably gave warning if the bonnet was raised - for either setting off an alarm or warning the driver if the bonnet catch comes adrift (I expect the former is more likely. Are there other security switches/wiring elsewhere?

Likely nowt particularly awry with the wiring harness once the ‘extras’ have been isolated and/or removed.

If the person who added the wiring was competent, the spade connectors will be safe - male will be on earth side and female ones will be live ones for the circuit.

MDP
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Re: Disconnected wiring

Postby MDP » Fri Jan 01, 2021 12:40 am

Thanks all for your comments. It sounds that there doesn't appear to be anything missing and the wires are probably not part of the original loom, so it's likely the wiring is something to do with an old alarm that seems to been partially removed. There is a siren still there but I can't find an alarm unit, or any other alarm components, other than the bonnet switch. I will try and trace the wires and remove any that aren't needed.

The car is a 1960 model and does have the pull start. The starter cable in the picture goes to a battery isolator switch, fitted through the bulkhead.

The starting problem, the car has been off the road for 13 years, I've changed the oil and filter and the engine turns over. There is spark at the points but nothing at the plugs, and having tested the coil today, the readings suggest it is faulty.

oliver90owner
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Re: Disconnected wirin

Postby oliver90owner » Fri Jan 01, 2021 7:36 am

What test readings/results suggested a faulty coil?

An easy way to test for basic operation by connecting one side of the coil to a 12V supply and, while holding the king lead about 6mm from an earthed metal surface (usually the engine), make and break the earthed side of the coil connection. A strong spark should occur between the king lead and engine(?). If there is clearly current through the points (when closed) an insulated screwdriver, or similar could be used to open the points for the test.

The lack of spark at the plugs could have a number of causes. Condenser, rotor arm, distributor cap, plug leads - and even plugs (but not usually all of them).

I suggest removing the plugs and turning over the engine, until oil pressure is achieved, before progressing further. Dry bearings need wetting with oil at the earliest opportunity!. Plug removal reduces loads on bearings and reduces the electrical load on battery and starter motor.

The electric fuel pump (and whole fuel supply) may need attention in readiness for starting, too.

MDP
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Re: Disconnected wiring

Postby MDP » Sat Jan 02, 2021 2:06 pm

Thanks oliver90owner, the test results for the coil are 3.2 ohms between the positive and negative, and 5.9 ohms between the HT terminal and either positive or negative.

I've tried a 12v supply to the positive side of the coil, when holding the king lead near the engine and making and breaking the negative side of the coil, there is a very weak spark from the king lead, so weak I could barely see it.

I've bypassed the fuel tank and fuel pump for now with a separate fuel supply hooked up.

myoldjalopy
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Re: Disconnected wiring

Postby myoldjalopy » Sat Jan 02, 2021 3:48 pm

"I've tried a 12v supply to the positive side of the coil, when holding the king lead near the engine and making and breaking the negative side of the coil....."
So we assume your car is negative earth? But even if the coil is wired the wrong way round, I would not expect the spark to be so weak you could barely see it...

oliver90owner
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Re: Disconnected wiring

Postby oliver90owner » Sat Jan 02, 2021 7:55 pm

Coil is dead. Primary is OK but secondary should not be 5.9 Ohms!

Edited to add: as long as the secondary resistance is not in kOhms .

MDP
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Re: Disconnected wiring

Postby MDP » Sun Jan 10, 2021 3:36 pm

myoldjalopy wrote:
Sat Jan 02, 2021 3:48 pm
"I've tried a 12v supply to the positive side of the coil, when holding the king lead near the engine and making and breaking the negative side of the coil....."
So we assume your car is negative earth? But even if the coil is wired the wrong way round, I would not expect the spark to be so weak you could barely see it...
I assumed the car was negative earth as the battery it came with was connected with negative to ground, however having just gone to fit a new coil I found that the positive terminal on the coil was connected to the distributor, where I would have expected to have seen the negative side connected, and the negative side of the coil goes to the ignition. So now I can't tell whether the car is meant to be positive or negative earth?

myoldjalopy
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Re: Disconnected wiring

Postby myoldjalopy » Sun Jan 10, 2021 3:53 pm

Most likely that is negative earth, if the battery is connected up as you describe, with the coil wired up the wrong way round. A clue would be - has it an alternator as opposed to dynamo? An alternator would strongly suggest negative earth. Wire your new coil up with the -ive terminal going to the dizzy and see what happens then.

MDP
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Re: Disconnected wiring

Postby MDP » Sun Jan 10, 2021 5:05 pm

Thanks myoldjalopy, I have just tried connecting the new coil up with negative to the distributor and the car started! It has a dynamo, not an alternator though.

myoldjalopy
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Re: Disconnected wiring

Postby myoldjalopy » Sun Jan 10, 2021 5:30 pm

Great news that she has fired up! :D It is entirely possible that the dynamo has previously been polarised to a negative earth state, and the battery connections suggest this to have been the case.

oliver90owner
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Re: Disconnected wiring

Postby oliver90owner » Sun Jan 10, 2021 5:37 pm

So you meant the secondary resistance was kΩ, not Ω.🙂

That would be a sensible and acceptable value.

geoberni
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Re: Disconnected wiring

Postby geoberni » Sun Jan 10, 2021 6:21 pm

Having the Coil connections reversed makes no significant difference to whether you get a spark.
It just means the spark is jumping from outer to inner on the plug. This can result in a moderately weaker spark and the plugs might wear out sooner apparently, but that's all really.

The change from Positive to Negative Earth is all about the Dynamo polarity and whether the battery charging works.

I'd had my Negative Earth car for over 18 months before I noticed the Distributor connections were still the same as the Manual diagram!

viewtopic.php?f=12&t=70183&hilit=distributor
Basil the 1955 series II

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MDP
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Re: Disconnected wiring

Postby MDP » Mon Jan 11, 2021 10:37 pm

oliver90owner wrote:
Sun Jan 10, 2021 5:37 pm
So you meant the secondary resistance was kΩ, not Ω.🙂

That would be a sensible and acceptable value.
The low tension reading was set to 200 and read 3.2, and the high tension reading set to 20K and read 5.9, not sure if this is kΩ or Ω as I've not worked with ohms before.

The new coil readings are 2.9 on the low tension and 8.9 on the high tension. From what I've read I was expecting this to be higher, but the car started so hopefully the new coil is ok.

oliver90owner
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Re: Disconnected wiring

Postby oliver90owner » Tue Jan 12, 2021 6:52 am

MDP wrote:
Mon Jan 11, 2021 10:37 pm
oliver90owner wrote:
Sun Jan 10, 2021 5:37 pm
So you meant the secondary resistance was kΩ, not Ω.🙂

That would be a sensible and acceptable value.
The low tension reading was set to 200 and read 3.2, and the high tension reading set to 20K and read 5.9, not sure if this is kΩ or Ω as I've not worked with ohms before.

The new coil readings are 2.9 on the low tension and 8.9 on the high tension. From what I've read I was expecting this to be higher, but the car started so hopefully the new coil is ok.
They work just the same as working in the voltage scale! Please don’t mistake a voltage reading of 2 on the 2000V range as meaning 2V - or we might be one member less on the forum!


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