Bacon Slicer Starter

[Tony Griffiths]

Does anyone have experience of a bacon-slicer stater motor spinning freely when not attached to the engine - yet with insufficient power to turn the engine over when attached? Battery good; commutator brushes not worn out; foot-operated switch sound; Bendix works; unit bolted down tightly.

[Dennis Nicholas]

Presumably you have checked resistance between each adjacent commutator segment?  Maybe one or more windings shorting/dry joint at coil to segment joint.  Enough magnetism produced to spin motor when free but not enough under load.
Measuring each would show up any fault, but not need to know what reading should be.....just that there is a difference.  Then knowing there is a fault this narrows where to look.

[Tony Betts]

hi tony.

silly question, is it actually motoring. or is it that the bendix is moving forward wilst driving. and touching the flywheel.

if the latter, then the little ball and spring that holds the bendix back is missing.

also check what movement there is in the button before it connects. the spring does break over the years.

ive had both these problems.

then check for brolen bendix spring.

tony

[Tony Griffiths]

Thank you both for your valuable help.

[Nick Turley]

One of the issues I have experienced with a chum's bacon slicer motor being very slow.
Is.
Somebody who had been there before me had cut the mica out between the com segments as you would do with a dynamo.
This done on a starter is a disaster.
The groves between the segments fill with a mixture of copper and carbon and the starter gets slower and slower until it does not work anymore.
The only solution for this is to turn the com down until there is mica at the top once again.
Or if done too deeply - find another
Starters turn slow and have big loads.
No centrifugal cleaning here.

Dynamos on the other hand are different and must have the mica on the com undercut.
The difference being that they spin very fast and their brushes are largely carbon (no copper) so are kept clean due to centrifugal force.
This is of course providing the charge rate is kept to a low level. The big dynamo killer is having the charge rate set too high.

[Tony Griffiths]

Hi Nick - I never knew that! And you are correct - the segments are filled with a mixture of copper and carbon.

[Mike Costigan]

If the grooves in the commutator have been cut back, can they not be rescued with a dribble of Araldite or similar?

[Dave Wortley]

Tony, got a spare motor which appears to work OK. Yours free of charge. ( Should have put it with the other spare bits that went with the chummy) Are you going to Hathersage tomorrow because I can bring it to the treasure hunt.

[Tony Griffiths]

Tony, got a spare motor which appears to work OK. Yours free of charge. ( Should have put it with the other spare bits that went with the chummy) Are you going to Hathersage tomorrow because I can bring it to the treasure hunt.

Thank you, David. Yes, I'll be there.