Lucas M35A Starter Motor

[cwchrisp]

Hello All,

I have a Lucas M35A starter motor as opposed to the CAV S-35-1 shown in Woodrow, fitted to my RM 1931.
Was the Lucas ever fitted to the Austin 7?
I have a spare CAV which tends to shower sparks when in operation, whereas the Lucas runs without much arcing.
Are brushes available for the Lucas, our cherished suppliers seem to sell the CAV ones, without copper tails.
Thanks for any replies.

[Jeff Taylor]

The Lucas M35A starter motor was fitted with a pair of NON copper tailed brushes Lucas part number 250055. I've checked eBay and there doesn't appear to be any on offer at the moment. Vintage Car Parts (formally Paul Beck) have them listed under part no. CB126 but appear to be out of stock - these same brushes fit both the 1932 - 37 Ford 8 & 10 and early 1930's Morris 8 cars with the M35A starter motor as opposed to the later M35G.

https://www.vintagecarparts.co.uk/search?query=brushes

[cwchrisp]

The Lucas M35A starter motor was fitted with a pair of NON copper tailed brushes Lucas part number 250055. I've checked eBay and there doesn't appear to be any on offer at the moment. Vintage Car Parts (formally Paul Beck) have them listed under part no. CB126 but appear to be out of stock - these same brushes fit both the 1932 - 37 Ford 8 & 10 and early 1930's Morris 8 cars with the M35A starter motor as opposed to the later M35G.

https://www.vintagecarparts.co.uk/search?query=brushes

Many thanks, Jeff.
Not sure whether non-copper tailed brushes would fit the carrier i have on the M35A, as the field connection is made directly to the brush via the tails with no independant way to connect the brush carrier or to connect with a screw through the brush, as in the CAV case.

Chris

[Jeff Taylor]

Chris,

I've just got round to checking the starter motor belonging to my late 1934 AVH Van (essentially the same as a late RP saloon but with a van body). The 6v starter is a Lucas M35A BN 11 (the BN signifies it's an Austin part) Part No. 250021 10 6 (this shows it was manufactured in October 1936 so not original to the engine crankcase). Mine definitely has the NON copper tailed bushes part number 250055. If you have a copy of John Platts 1983 The Austin Seven Centre Catalogue, there's an exploded diagram of the Lucas starter on page 153 showing the NON copper tailed brushes attached to the two pivoting carriers by a machine screw through the bush - each of the copper connection cable ends have soldered open eyelets which are held against the brushes by the machine screw / spring washer. Platts shows these Lucas starters were fitted between 1932 and 1939. I suppose it's possible someone in the past has fitted a different end plate to your starter. The M35G starter fitted to the Morris 8 Series E used copper tailed brushes - Lucas Part No. 255659 perhaps these might fit your end plate?

[cwchrisp]

Chris,

I've just got round to checking the starter motor belonging to my late 1934 AVH Van (essentially the same as a late RP saloon but with a van body). The 6v starter is a Lucas M35A  BN 11 (the BN signifies it's an Austin part) Part No. 250021  10  6 (this shows it was manufactured in October 1936 so not original to the engine crankcase). Mine definitely has the NON copper tailed bushes part number 250055. If you have a copy of John Platts 1983 The Austin Seven Centre Catalogue, there's an exploded diagram of the Lucas starter on page 153 showing the NON copper tailed brushes attached to the two pivoting carriers by a machine screw through the bush - each of the copper connection cable ends have soldered open eyelets which are held against the brushes by the machine screw / spring washer. Platts shows these Lucas starters were fitted between 1932 and 1939. I suppose it's possible someone in the past has fitted a different end plate to your starter. The M35G starter fitted to the Morris 8 Series E used copper tailed brushes - Lucas Part No. 255659 perhaps these might fit your end plate?

Hi Jeff,
Thanks for checking and the infomation, very useful.
The Lucas fitted to my RM is M35A BN11 Part 250021 12 0. (Guess that is December 1930, correct for the car)
I looked at John Platt 1983 and it looks like the CAV arrangement, apart from a front bush rather than the roller bearing in the CAV?
I have found a set of NOS brushes on e-Bay https://www.ebay.co.uk/itm/LUCAS-M35G-ST...2749.l2649.
I would need to modify the double brush to make it a single and solder it onto to the field winding. The other one with the earth connection is fine.
I never knew car detective work was so interesting!!
The M35G end plate complete would fit, I think, but would need the through bolt holes drilled to suit my starter.
I hope I am on the right track!

[Jeff Taylor]

Hi Chris,

Unfortunately I'm not familiar at all with the earlier CAV unit having never had one. The Lucas 251108 set you've linked to on eBay fitted a wide variety of post war cars including Austin's between 1949 and 1955, Morris 1948 to 55 and Ford Anglia and Prefect 1953 and 54 among others. All these vehicles used an M35G / 1 or L3 / 1 starter motor.

[Bob Culver]

Without fully pondering this post, note that if substituting a 4 brush end plate and using as 2 brush the live and earth brushes will and should remain  at right angle as the 4 brush. The brushes must be in exactly same position wrt the field poles.

[cwchrisp]

Without fully pondering this post, note that if substituting a 4 brush end plate and using as 2 brush the live and earth brushes will and should remain  at right angle as the 4 brush. The brushes must be in exactly same position wrt the field poles.

Bob,
Thanks for that. I will make sure the brush orientation is exactly in the same position as on the original end plate.