Practice Starter Motor Task - Monday 19th January 2015

As a result of my absence Monday and Tuesday last week, due to "Bongo issues", I was caught a little on the back foot this week.  I arrived expecting to re-commence the wheel bearing practice task, for which I had already completed the planning part, however the pace of events were rapidly scaled up yesterday, in order to try and get all the Garston Lab jobs  (for all Group A Students), out of the way "pronto"!  Flexibility and adaptability are key components in "real life", something I do like to rise to when presented. 

My outstanding tasks in the Garston Lab were thus Starter Motor and Cylinder Head, both of which I am pleased to report have now been completed to a satisfactory standard (although it is one, along with Alternator, Rear Differential and Gear Box, that I would wish to gain a 2nd run at on my own pace prior to examination).  Due to the recent escalation of pace however, I do find myself only "physically" able to provide a current blog on the Starter Motor from yesterday (I think)?!.

Isaac had already previously done his planning, but had not yet taken any live measurements or readings on a rig or a vehicle, so he waited patiently whilst I played catch up with the planning, and accompanied me with various passable impressions of engines using a dump valve - which is good for the testing of patience and focus levels, and I passed! 

With me up to date, it was time to strip a Starter Motor, and with Isaac in prime position for the tools, and also with a Starter Motor already in his hands, it was a case of observing closely what was happening before me. This lad should be working for Marconi or such like! Outstanding natural ability!

Armature with
Pinion Gear (Top)
Removed?

Planetary Gear Set
within to multiply
Torque at Pinion on
Flywheel

For myself, this was the first time I had seen the inner workings of a Starter Motor, and (as already intimated), it happened so fast I really would wish to do it again at my own pace.  I am not the quickest, but I am thorough!

Body of Starter
Fixed Magnets
Within

With the Starter stripped and measurements taken of the carbon brushes, it was then reassembled, and then bench tested using a 12 Volt Car Battery and a set of jump leads. The Motor turned and the pinion operated satisfactorily.

It was then time to gather live readings of  a Starter Motor Current Draw, and we utilised the Vauxhall Vectra next door (Coil disabled), with an Inductive Amps Clamp.

Current Draw of Starter on Cranking
(Coil Disabled)

Measuring Insulated
Voltage Drop

We then needed to test the Voltage Drop, on both the Insulated circuit and the Earth Return, both of which should not exceed 0.5 Volts. 

We utilised a live rig for this purpose, for ease of access. Results returned 0.09 V and 0.20 V respectively, so serviceable.

We then had to provide a coloured wiring diagram of a Starter Motor for inclusion within our portfolio's, and then complete our job cards, with our report of serviceability and findings accordingly.  With all signed off as satisfactory by our tutors, it was then just a case of tidying up our tools and work areas, prior to departing for respective evening destinations.  Blur of a day but most informative and absorbing.  Isaac - you are a star in waiting indeed!