2015 D40 slow crank start

[Rich_sp]

Hi there. Wonder if anyone can help?

Over the weekend, my Navara (last of D40s, 2015 model, 2.5TD, 116k on clock) has developed a slow cranking issue when starting up.

As yet, it's not failed to start, and runs fine once engine starts. Had battery replaced which a mechanic friend thought would fix it, but it's not really much, if any, better. Could it be a starter motor issue or something else?

Battery and alternator tested and all good

Any advice appreciated!

 

[Old.Tony]

I've had the slow start issue and it's been battery every time, but that doesn't mean it can't be a damaged solenoid (high current arcing on the contacts will ruin them) or the starter motor itself isn't coping.

Age (of the vehicle) will tend to loosen things up - lower compression (worn rings/bores) and make it easier to start, so if the battery is good it shouldn't have any trouble starting it. A test isn't always perfect, I had a bad battery test good and even made the testing gear start smoking! I replaced that battery and everything worked properly again.

Don't try jump-starting it off a petrol car, even V8s don't use more than around 300amps to turn over. These little 4-bangers pull between 500 and 550 amps to turn over.

If a really good (as in it starts another diesel really easily) battery doesn't get yours going in a similar fashion, then you'd start examining the starter and solenoid.

 

[Rich_sp]

Thanks. Will explore both of these options with a garage. Mechanic friend was convinced it was the battery (though only two years old) as it was reading 'poor health' on the tester. So surprised it wasn't that. He seemed to rule out a starter issue initially, as he didn't think a faulty starter would behave like that.