New adventure begins in France!

[Steves_TR6]

43 minutes ago, BlairP said:

It is not; I thought the switch should show continuity as does a wire: without needing to be energised. Could I be wrong about that? (And good idea about the fuse!)

The switch works like any other switch, opening and closing continuity as you operate the key

try inserting and turning the key and you should have continuity across the two big terminals

good luck !

[RobH]

If you do fit a fuse in the battery supply as Steve suggests, use it only for static tests - don't try to start the engine.  The starter draws a very large current and will blow any fuse instantly. 

[BlueTR3A-5EKT]

Ever the cheap way for me.

We tie a single strand of wire  (taken from a multi strand cable of the old loom light circuit perhaps) one end to the battery earth  terminal and the other to the appropriate battery cable clamp.  Then if the wire strand burns out it can only touch the earth it was originally connected to.    This forms an easy blow and visible fuse if there are any unwanted short circuits.

 

[BlairP]

First of all: Sorry for not taking pictures. I was to intent on getting to the result.

I drilled out the switch and separated the two halves, and found both the inside case and internals covered with corrosion and sandblasting dust (which I thought I had successfully removed). Thirty minutes or so with various brass-wire wheels, and all was gleaming, especially the copper internals. Et voila! Continuity across the poles in the on position, and nothing in the off!

Thanks guys!

[BlairP]

Greetings all, and Happy Holidays. Just when we thought it might be safe to go back in the water, huh?

In any case, in preparation for my first start, I've been testing the electrical system, and I've come up against something that has stumped me. I've installed a 55-amp alternator from Powerlite (sold by Revington), and wired it according to the instructions (see pic below).

The issue is: It is giving me continual battery power through the brown excitation wire, which leads to terminal 21 on the Classic Technologies fuse box I've  installed (see wiring diagram). This is feeding directly through to terminal 7, meaning the fuel pump, hooked to terminal 7, runs as soon as I hook up the battery. If I unplug the alternator plug, everything works as it should. The alternator itself is giving me continuity through the winding when it's plugged in.

The alternator has three unused terminals on its back (as per the pic), including a single male plug. I had assumed these were simply alternate connections if not using the single 3-wire plug. Could that be wrong?

I've tried to call Powerlite, but they're out until Jan. 4, and I'd really like to get this sorted.

Does anyone have any insights? Ideas?

Thanks in advance,

Blair

 

Edited December 26, 2021 by BlairP

[BlueTR3A-5EKT]

Does anything on here from Brise help?     https://brise.co.uk/?v=79cba1185463
 

 

Edited December 26, 2021 by BlueTR3A-5EKT

[RobH]

This is an A127 alternator. The connector has two large spades and one small one.  

Both of the large spades are positive output - you can use either or both to connect to the battery.   (I must say the wire you have going to that connector looks rather weedy for a 55 Amp connection. Are you sure it is at least 8.5 square mm in cross-section?)

The small spade is for the dashboard warning light.

The alternator connection  shown on the Classic Technologies wiring diagram is wrong . There is no excitation input to this alternator so the brown wire from pin 21 is not needed.  if you have connected it, that is the cause of your problem.

There is no earth wire.  Connection to earth is through the alternator body.  

(Note that the bright-plated terminal on the right, marked B+ is also an output. It would be a very good idea to put an insulating cap over that because you are not using it.  An accidental short to earth could be catastrophic  ) 

 

==

Edited December 26, 2021 by RobH

[BlairP]

Genius! Thanks so much Rob! If you're ever passing through Burgundy, there's a lovely bottle of wine awaiting you!

I unhooked the excitation wire, and everything works as it should. Now to add the fluids, check for leaks, cross my fingers and...

Blair

[RobH]

Glad it's fixed  . Joyeux Noel. 

[BlairP]

Greetings all, from a frustrated garagiste in Burgundy. I’ve been systematically eliminating bugs so I can start my rebuilt ’69, but I’ve not run up against something I do not understand: My (rebuilt) starter does not seem to have enough power to start the engine.

Here’s what I’ve done:

Turned the crank by hand. It turns easily.

Bench- and load-tested the starter itself: it’s good and very strong.

Removed the spark plugs and turned the key. Turns perfectly and circulates oil.

Checked the grounds on the battery and starter.

Ensured the battery is fully charged, and even tried other batteries.

Yet when I turn the key, I get an effect that seems like the starter’s not getting/giving power. The engine turns slowly once or twice, as though the battery was low; but it’s not. I’m getting frustrated, as this bugger should be ready to start!

Any thoughts/ideas would be greatly appreciated.

Blair

[Mike C]

Do you have a good, fully charged battery? Can you check the voltage on the battery -it should hold something like 10V while the starter is cranking with the plugs in.

[Waldi]

Blair,
Do you have the battery earth strap fitted to the gear box (and the body)?
If not, the current flow is restrained.

Waldi

 

[RobH]

This sounds to be an electrical fault despite the checks you have done. Can you measure the voltage at the starter motor when cranking? That might give a clue. 

Have you tried a substantial earth return connection from the vicinity of the starter direct the battery? A poor connection somewhere will drop voltage and give weak cranking.  If that doesn't help and the voltage looks OK  it could be a problem with the solenoid contacts on the starter itself or brushes/commutator. How did you bench test the starter on-load?

 

[roy53]

As both Rob and Waldi mentioned i have found this problem , same as you describe .  connect up direct from - direct to the engine. I used a jump lead.

Roy

[BlairP]

1 hour ago, Waldi said:

Blair,
Do you have the battery earth strap fitted to the gear box (and the body)?
If not, the current flow is restrained.

Waldi

 

Yes, with the paint removed at body contact point for good ground.

[Tim D.]

If you are re-using old wires from the battery that are covered by plastic covering very carefully check that they are not broken internally. I had a similar problem. The multimeter said the wires were all fine, but then it is only loading the wire up with milliamps and even a thin wire strand will work. When you load it up with the start it is pulling quite some Amps and then you need all the strands.. In my case the wire from the battery had almost completely broken where it connected to the starter and the heatshrink was covering the break!.

The only real test as mentioned already is to short circuit the line with a good set of jump leads

Cheers

tim

[Motorsport Mickey]

Roy, you have a couple of Personal messages.

Mick Richards

[PodOne]

The earth battery clamp and connector might look ok externally but the interface between the two could be badly oxidised after 50 years. I'd be tempted to change out the battery leads anyway.

Interested to hear what the issue turns out to be.

All the best Blaire I'm sure she will run.

Andy 

[BlairP]

23 hours ago, RobH said:

This sounds to be an electrical fault despite the checks you have done. Can you measure the voltage at the starter motor when cranking? That might give a clue. 

Have you tried a substantial earth return connection from the vicinity of the starter direct the battery? A poor connection somewhere will drop voltage and give weak cranking.  If that doesn't help and the voltage looks OK  it could be a problem with the solenoid contacts on the starter itself or brushes/commutator. How did you bench test the starter on-load?

 

I will measure the voltage today at the points suggested, and try a direct earth from the battery. The starter was tested under load by an auto-electric shop here that has a test rig where more and more resistance can be applied to the running starter to try and stop it. They were unable to.

One other thing I forgot to mention in my original description is that the starter itself (not the solenoid) gets hot when trying to start the engine.

[BlairP]

12 hours ago, PodOne said:

The earth battery clamp and connector might look ok externally but the interface between the two could be badly oxidised after 50 years. I'd be tempted to change out the battery leads anyway.

Interested to hear what the issue turns out to be.

All the best Blaire I'm sure she will run.

Andy 

Already done. Both battery leads are new.

[RobH]

It's perfectly normal for a starter to get hot  if you are cranking, or trying to crank,  for more than a few seconds. That power has to go somewhere.  (200A x 10v = 2kW). 

It sounds as though there cannot be a problem with the actual starter motor and the engine is free mechanically with the plugs out.  That just leaves a poor electrical connection or somehow excessive compression ratio...........?    

[John L]

Could it possible that the starter drive gear is too tight onto the flywheel gear, have you tried to loosen the starter bolts a little and then try and start?

John

[Mike C]

8 hours ago, John L said:

Could it possible that the starter drive gear is too tight onto the flywheel gear, have you tried to loosen the starter bolts a little and then try and start?

John

If it was a ring gear or starter mounting alignment  problem the starter wouldn't spin with the plugs out. I'd be looking at the starter power supply electrics.

[BlairP]

Thanks for all the ideas; the engine is now turning over correctly, and I'm going to try to start it this weekend.

What I did, and found:

I removed the starter again, cleaned up all the contact points, took it apart and blew it out, polished the brushes and commutator, and reinstalled it. THIS time, however, I followed the Brown Book installation steps, and added two buffed-up star washers between the starter and the heads of the bolts that retain it - for a better ground, according to the BB.

Before hooking up the battery, I put on the voltmeter. Battery showed 12.7V.

Hooked it up, unhooked the coil, and turned the key. Voltage dropped to 9.4, but the engine turned over correctly, and I got oil pressure.

I've got a friend coming this weekend to lend a hand and see if we finally can start her. Fuel pressure is correct to the MU, timing has been set statically, so fingers crossed!

Thanks again!

Blair

Edited April 9, 2022 by BlairP

[John Morrison]

Hope it fires into life Blair.

John.