Lucas Bendix Starter

[Z320]

Hi,

who knows the reason for the solid spring on the Lucas Bendix starter?

Is it only there to hold the unit together?

Reason: I want to make it shorter for my MX-5 gearbox project, therefore the spring has to go.

Ciao, Marco

[peejay4A]

I think it’s there to act as a buffer when the engine starts and the pinion is thrown out of engagement. 

[Z320]

H Pete,

I also always thought that, but yesterday evening in my workshop i realized:

- the ring gear on the flywheel Bendix starter pinion are spure-toothed, this causes no forces in or out

- the starter pinion probable is only thrown out by this tiny soft spring inftront the Bendix pinion

This reminded me to one of my older videos on Youtube.

bendix starter working

There must be another reason for this solid spring, perpaps only a simple nut on the end can not hold the ecceleration?ny other ideas from other members?

Ciao, Marco

[RAHTR4]

Hi Marco,

This appears to be the explanation from one of the Lucas Training Manuals.

Regards, Richard

[Z320]

Hi Richard,

thank you very much for your effort!

Indeed this is the explanation - but what I realize is different:

as told above only this tiny spring visible on your illustration "throws" the Bendix pinion out as soon as the forces and friction on the teeth are zero (same speed).....

I have to take a closer look and make a desicion:

buy a new high torque starter - this are more costs and not what I want with my "low cost" gear box project (and I don't like the noise of it)

or modify one of my original starters and see what happens.

Thanks again, Marco

 

Edited August 15, 2020 by Z320

[peejay4A]

Would a pre-engaged starter from a 6 cylinder engine fit?  

[Z320]

Fit - perhaps, work - no, because a TR4A needs a10 teeth starter, a TR6 needs 9 teeth.