Date code confirmation

[geoberni]

The Lucas Starter motors had both a Type and a Model Number.

The Type in this example is the M35G.
M - Starter Motor
35 - 3.5" Diameter Yoke. They also made 325 (3.25"), 418 (4 & 1/8th") and 45 (4.5") Note the metrication of the measurement except for the 1/8"...
G - Die-cast commutator end bracket or frame.
(The G-1 was also a Die-cast commutator end bracket or frame, but for 4-brush machine.)

I imagine the J suffix relates to the change to the flat commutator, but the manual I got this from did not cover those later designs.

The actual part number or model number then accounted for the actual configuration, of mounting plate size, Voltage, CW or CCW rotation, bendix size/teeth etc.

My Lucas Technical Manual reference document also only takes the 2507* sequence up to 25075 which was as follows
M35G-1. 12v.; clockwise; earth return. Used on Austin 'Seven' (850) and 1/4 ton Van 1960, Morris 'Mini-minor' and 'Mini-van' 1960.
(The G-1 was a Die-cast commutator end bracket or frame, 4-brush machine.)

So returning back to Stephen's example, I did some digging elsewhere and came up with the 25079 as being fitted to the likes of MG Midget, Triumph Spitfire and Triumph Herald, it's a M35G with 9-tooth Bendix and counter-clockwise rotation.

The M35G-1 for the Minor is CW rotation.

So best not try that rusty one on your Minor.

[svenedin]

The Lucas Starter motors had both a Type and a Model Number.

The Type in this example is the M35G.
M - Starter Motor
35 - 3.5" Diameter Yoke. They also made 325 (3.25"), 418 (4 & 1/8th") and 45 (4.5") Note the metrication of the measurement except for the 1/8"...
G - Die-cast commutator end bracket or frame.
(The G-1 was also a Die-cast commutator end bracket or frame, but for 4-brush machine.)

I imagine the J suffix relates to the change to the flat commutator, but the manual I got this from did not cover those later designs.

The actual part number or model number then accounted for the actual configuration, of mounting plate size, Voltage, CW or CCW rotation, bendix size/teeth etc.

My Lucas Technical Manual reference document also only takes the 2507* sequence up to 25075 which was as follows
M35G-1. 12v.; clockwise; earth return. Used on Austin 'Seven' (850) and 1/4 ton Van 1960, Morris 'Mini-minor' and 'Mini-van' 1960.
(The G-1 was a Die-cast commutator end bracket or frame, 4-brush machine.)

So returning back to Stephen's example, I did some digging elsewhere and came up with the 25079 as being fitted to the likes of MG Midget, Triumph Spitfire and Triumph Herald, it's a M35G with 9-tooth Bendix and counter-clockwise rotation.

The M35G-1 for the Minor is CW rotation.

So best not try that rusty one on your Minor.

That's very helpful of you Berni

Well over 30 years ago I was given various parts by an old mechanic. Clearly this particular starter motor is not for a Minor! Good to know. I will now mark that starter as to be offloaded at some point.

An amazing coincidence actually. Just a few minutes ago I was watching an episode of "Bangers and Cash: Restoring Classic". They were restoring a Renault Dauphine. The car would not start and it turned out that it was the wrong starter motor which turned the wrong way!



Stephen

[geoberni]

That's very helpful of you Berni

Well over 30 years ago I was given various parts by an old mechanic. Clearly this particular starter motor is not for a Minor! Good to know. I will now mark that starter as to be offloaded at some point.

An amazing coincidence actually. Just a few minutes ago I was watching an episode of "Bangers and Cash: Restoring Classic". They were restoring a Renault Dauphine. The car would not start and it turned out that it was the wrong starter motor which turned the wrong way!



Stephen

No problem.
The questions posted got my interest as I'd never really looked in depth at the manual pdf I had downloaded a few years back.
When I found it didn't go as far as the 25079, I was even more curious....
Understanding these details is good knowledge for when I'm looking at bits at autojumbles...

For anyone interested in the Lucas Manuals the only ones I've ever found seem to up to 1960, no sign of anything dated later.. .
This MGA site is a reliable place for them:
https://mgaguru.com/mgtech/books/lucas400e.htm

[Bill_qaz]

That's very helpful of you Berni

Well over 30 years ago I was given various parts by an old mechanic. Clearly this particular starter motor is not for a Minor! Good to know. I will now mark that starter as to be offloaded at some point.

An amazing coincidence actually. Just a few minutes ago I was watching an episode of "Bangers and Cash: Restoring Classic". They were restoring a Renault Dauphine. The car would not start and it turned out that it was the wrong starter motor which turned the wrong way!



Stephen

No problem.
The questions posted got my interest as I'd never really looked in depth at the manual pdf I had downloaded a few years back.
When I found it didn't go as far as the 25079, I was even more curious....
Understanding these details is good knowledge for when I'm looking at bits at autojumbles...

For anyone interested in the Lucas Manuals the only ones I've ever found seem to up to 1960, no sign of anything dated later.. .
This MGA site is a reliable place for them:
https://mgaguru.com/mgtech/books/lucas400e.htm

Berni, thats the same one I posted a link to the starter motor section from.
Great resource

[geoberni]

Berni, thats the same one I posted a link to the starter motor section from.
Great resource

Yeah, I realised that when I did it. I've found other sites in the past, the Series One Landy site has the same, still missing Sect 10 covering the M35G, which is annoying.
What sort of well organised company has a Technical Manual where M35J is in sect 4 but the M35G is in sect 10, for crying out loud
Oh yeah.... why am I asking that....

[Bill_qaz]

Berni, thats the same one I posted a link to the starter motor section from.
Great resource

Yeah, I realised that when I did it. I've found other sites in the past, the Series One Landy site has the same, still missing Sect 10 covering the M35G, which is annoying.
What sort of well organised company has a Technical Manual where M35J is in sect 4 but the M35G is in sect 10, for crying out loud
Oh yeah.... why am I asking that....

We were always bemused by the parts manual authors putting components in completely inappropriate sections, instead of asking the engineers what the component relates too.
EG. The voltage dropper for 12 v cab items like a radio was in chassis section, probably because thats what it bolted too and they didn't know what it was

[geoberni]

We were always bemused by the parts manual authors putting components in completely inappropriate sections, instead of asking the engineers what the component relates too.
EG. The voltage dropper for 12 v cab items like a radio was in chassis section, probably because thats what it bolted too and they didn't know what it was

Or Morris/BMC putting the 'Radiator and Fittings' in the Mechanical Service Parts, but the 'Heating and Ventilation' in the Body Service Parts....
The same water going into 2 different books and the electric fan not being in with the other electrical bits like Wiper Blades....
That really drove me nuts when I was first trying to find the heater details.....

[geoberni]

That's very helpful of you Berni

Well over 30 years ago I was given various parts by an old mechanic. Clearly this particular starter motor is not for a Minor! Good to know. I will now mark that starter as to be offloaded at some point.

An amazing coincidence actually. Just a few minutes ago I was watching an episode of "Bangers and Cash: Restoring Classic". They were restoring a Renault Dauphine. The car would not start and it turned out that it was the wrong starter motor which turned the wrong way!



Stephen

Hi Stephen

I can't edit my earlier post now...
Looks like I was a bit hasty is describing the 25079 as CCW. I think the site I looked at was incorrect.
It seems as though some retailers are listing Starter direction when viewed from the back end.
Lucas describe the rotation when looked at from the Bendix end

Delving deeper, I've found some photos of 25079 and they are marked as CW when viewed on the Bendix end.

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[svenedin]

Thank you Berni,

When I look at my photograph, it is clear that the arrow indicates clockwise rotation as viewed from the Bendix end as you say. We know that we start a Minor engine by turning the starting handle clockwise. The starter motor has to engage the pinion gear and turn the flywheel, via the ring gear, clockwise as viewed from the front of the engine. That means that the starter motor has to rotate anticlockwise as viewed from the front of the engine or clockwise as viewed from the Bendix end. So, my old mechanic friend all those years ago DID give me the right starter motor!

Stephen

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[geoberni]

It is a salutary lesson to double check supplier descriptions.
In the absence of a Lucas document, I just did a search for the tech spec of the 25079 and ignoring the AI results, clicked on a couple of retailers offering 25079, which these days is just one of several part numbers in a long list of 'compatible part numbers'.

This morning I've done some more investigating, tenacious (stubborn) as I am, and have followed the trail of retailers to this American supplier ...
https://www.rareelectrical.com/i-268782 ... 5079d.html

Even this company are not the manufacturer, just a wholesaler/distributor, but the retailers I had looked at all lead back to here.
The complexities of parts distribution and how a listing error can spread out.

caveat emptor....

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[Bill_qaz]

Looked at RB106 no numbers stamped in casing like Stephen just a stick on label, so guessing not OE?

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[svenedin]

RB106 model number and date is on the base part on the left hand side as mounted in the car. Sticky label if present is on the lid. What you have there Bill is a later genuine Lucas replacement as that silver label was not used in the 1960’s. I remember the silver label from a unit I installed in 1989. It fell off decades ago!

Stephen

[Bill_qaz]

Ah I looked on top I'll look on side when back at the car.
The label was on the cover but peeling, so took it off to photo then stuck it back on.
Thanks Stephen

[geoberni]

I'm not sure about Stephens info on the sticky label.
I don't know when the NCB101 number started being used.

Back when it was OE, there were numerous different versions for different applications.
The Workshop Manual makes it look like there were only 2 Control Boxes on Minors, the one that had the fuse box integral to it, and later the RB106/2.

If you look at the published Lucas fitment data there were some 10 part numbers across 3 model numbers just up to 1960, when the data I have was published.
Starting with the RF95/2, then the RB106/1 and the RB106/2.
Visually the difference between the 2 RB106 models is screw terminals became Lucar push on.

As a general rule, the different part numbers denote internal design differences, the suffix change denotes minor inconsequential differences.

As with Stephen's photo, my two spares are both RB102/2, pt no 37290F, one dated 1-68, the other 33-80.
I guess after '68, they were done altering the design of Dynamo Control Boxes.
Underneath, the '68 shows signs of the foam strip possible getting hot as it's gone hard and crisp, while the '80 one the foam is still pliable but at some time the car it was on had a problem, because the link between A/A1 had melted like a fuse and then been repaired.
I've tested them both on my car and both work, controlling a steady voltage.
The white 9 under the '80 one is from the trader wanting £9 for it at the autojumble. I can't remember what the other one was, but it must've been a similar price.

I've just noticed, as well as not have LUCAS on the side, the Steering wheel symbol is the opposite way up on the '68??

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[svenedin]

I'm not giving a precise date, just saying that the silver sticky label wasn't used in the 1960's as far as I know. When Bill finds the numbers on the base, all will become clear. Although having said that, these were sold as reconditioned units as well and those will have the original date on the base but a later sticky label.

Stephen

[POMMReg]

Have Lucas parts books if you want item(s) looked up

[geoberni]

I'm not giving a precise date, just saying that the silver sticky label wasn't used in the 1960's as far as I know. When Bill finds the numbers on the base, all will become clear. Although having said that, these were sold as reconditioned units as well and those will have the original date on the base but a later sticky label.

Stephen

Yes, it'll be interesting to see what he comes back with. The sticky label seems more of a 'modern' thing
A bit like bearings being packed in waxed paper and grease inside their box... and then suddenly they're being heat sealed in a plastic bag inside the box instead.

[Bill_qaz]

Will know more when I check the body in the right place
I suppose its also possible the cover could of been replaced.

Will the date code be on cover of the flasher/ stoplamp relay on the face towards the engine where it's stamped Lucas? I need to give it a clean up to read it.

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[geoberni]

Date on the DB10 Relay just above the numbers for Terminals 6 & 7....

I have a modern replica in my car, which is useful in a way as the modern relays take much less current than the originals. But I've brought a couple of old originals at jumbles to see what I can do with them.
This one, as best as I can tell, is likely 2 55...
When the cover is really pitted, you can sometimes still read it from the inside.

I did a feature for Minor Matters on the DB10, which was in the Nov/Dec 2024 edition.

.

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[Bill_qaz]

DB10 Info on housing, so I believe 9 62 so matches wiper motor period Sept 1962.

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