New battery 14mths old tested with multimeter with engine off, reading 12.85v.
struggles to start with appearance of flat battery then suddenly bursts in to life with enough energy to start the engine.

After 5mins tick over stopped and tried to restart 'click' struggled then eventually started after third key turn.
Thought I'd throw myself to the 'how to club' before calling garage to do a 'load' test on the battery .Relay and solenoid. def not charge related had fully charged it 12 hrs ago.
Many thanks Bob

Bob, November 2017

Thanks Safea and cdc it turns out to be the starter is being retired in 2weeks time the earliest garage can deal with it.
Multimeter set at 20 DCV
Battery engine static 12.4
Battery enging running 14.35
Alternator tests fine (shows on engine running test)

Bob, November 2017

Sounds like your starter motor might be on the way out

cdc, November 2017

Many thanks safea will get a friend around to do the testing as he's more used to using a Multimeter.

Again thank you.
Bob

bob, November 2017

If you can, check battery voltage AT THE BATTERY TERMINALS when the car is cranking. It'll be a bit down on 122v but hopefully not much.

Check all the high current connection: Battery to solenoid, solenoid to starter, starter (or engine block) to chassis, chassis to battery.

If there is a poor connection somewhere, you MIGHT be able to feel it if a terminal or connection is warm IMMEDIATELY after cranking. - That did work for me once but it's a bit of a log shot.

You could also check for volt drops by measuring the voltage across each connection whilst the engine is cranking.

Battery terminal itself to the metal of the connector; Should read zero whilst cranking. Metal of the battery terminal connector to the starter terminal; Should read zero whilst cranking. Starter motor to battery negative terminal: Battery terminal itself to the metal of the connector; Should read zero whilst cranking.

One other thought is it could be starter motor brush problems.

Battery in the car with the engine running should read maybe 14.5 volts. Lower would suggest not charging. -possible alternator or regulator issue.

safea, November 2017