remind me how to test a battery

[rapidyellow]

the mrs pug 308 hdi was a slow starter, as it was easy to do we bought a new battery for it, and on taking the old one out it was too small and the wrong type for the car, an 027. we bought the correct 096 from Tayna. The new battery didnt make a great deal of difference to be honest.

that was at the end of oct this year [2021], however yesterday it failed to start.

jump leads onto another battery didnt help it so I took the battery back out and put the 027 back in and it started.

the new 096 [now discharged as taken off the car] I tested with a multimeter and it was at 11.5 volts

I have got it on a 6ah charge now, will leave it until tomorrow afternoon.

car is charging ok, leads and connections are all ok, no corrosion.


are there any other tests I can do with my multimeter to check the battery is ok after a charge?


going back to original fault of it being a slow starter, by that I mean its slow to turn over, and how I understand it is for a diesel it needs to spin a little faster to build better compression to get it started, with the new battery it wasnt much better so we will replace the starter motor for a new one over the xmas holiday.

[welshpug]

its not the compression that needs building up, its the fuel rail pressure, without a certain pressure threshold reached the ecu will not fire the injectors.

still a slow starter will not help, have you cleaned the earth connections?

not much you can do with a meter other than simple voltage tests, make sure you don't over charge and buckle the plates though

[rapidyellow]

connections I can access are all good, we have ordered a new starter anyway and a friend of mine will fit it for me who is a mechanic, he will make sure connections down there are good.

I have a 207hdi same engine, it starts perhaps with half a turn of the flywheel and therefore instantly, this 308 is just slow. Its runs perfectly normal though when started.

[ferny]

Not uncommon for s brush to seize in the starter to cause what you describe. Probably about £12 to fix and very little time needed to check.

[winchman]

Had this my self once I fitted a high capacity starter it was like a new car, I suspect the old starter damaged my battery.
I use a proper digital battery tester

[truckdoctor]

Carry out a voltage drop test when cranking to test for poor connections. That's battery pos to started solenoid connection expect less than one volt. Do the same with battery neg and starter body. If all is well then expect starter or battery defects.

[rapidyellow]

after a charge overnight the new battery was put back in and was ok, in the meantime a new starter was bought and a mechanic friend fitted it for us, car starts instantly now just like it should.