Slow morning cranking

[Garymallissa]

Hi,

We have just purchased a 2003 multi space 2.0 HDI 
In the mornings it turns over very slowly but does start, just! Once started it will start just fine all day, until the next morning.
The battery is 540 amp which I tested and got a reading of 12.1v 
It was put on charge and was soon up to 12.5
And 15.4 when running
Still very slow turning in the mornings!

I was wondering if it could be the battery as someone suggested to me that it should have at least a 650amp

I did also read that it could be the starter but surely if it was the starter it would be slow all of the time?

Thank you

[Sol]

It should read 14.4V when running, 15.4V is too high. (unless that was a typo) - the simplest thing is try another battery. It takes no time at all to rule out, unlike the starter which is a way bigger job to change and much harder to verify.

When it is warm, is it not the case that it starts so quickly that you never notice the cranking speed and it just "seems" to start ok? (since the oil is now warm and thin). Overnight cold means it takes a fair lump of current to swing that diesel engine over. Once it's warm, it needs way less power to crank it.

I don't know if you can get a battery from someplace like Halfords and return it if that isn't the issue, or just take the hit and buy a new battery - it will never ever be a bad move to have a new one.

And I agree with the statement that a bad starter is always bad. It usually wouldn't improve after being used. There are places which can actually load-test the battery, like kwik-fit or a garage nearby. That could be a starting point.

I have this bad-boy, so never need to guess if I have a potential battery issue: (hook up, connect with Bluetooth from the phone and crank away, full battery testing in your hand at any time.)

https://www.amazon.co.uk/Battery-Crankin...B0BHQYS6WZ

[Garymallissa]

It should read 14.4V when running, 15.4V is too high. (unless that was a typo) - the simplest thing is try another battery. It takes no time at all to rule out, unlike the starter which is a way bigger job to change and much harder to verify.

When it is warm, is it not the case that it starts so quickly that you never notice the cranking speed and it just "seems" to start ok? (since the oil is now warm and thin). Overnight cold means it takes a fair lump of current to swing that diesel engine over. Once it's warm, it needs way less power to crank it.

I don't know if you can get a battery from someplace like Halfords and return it if that isn't the issue, or just take the hit and buy a new battery - it will never ever be a bad move to have a new one.

And I agree with the statement that a bad starter is always bad. It usually wouldn't improve after being used. There are places which can actually load-test the battery, like kwik-fit or a garage nearby. That could be a starting point.

I have this bad-boy, so never need to guess if I have a potential battery issue: (hook up, connect with Bluetooth from the phone and crank away, full battery testing in your hand at any time.)

https://www.amazon.co.uk/Battery-Crankin...B0BHQYS6WZ

Thank you for the info, yes it was a typo ??‍♂️ 
I will get a battery sorted I think. Can you recommend a battery size?

[Sol]

Looks like a 096 is the big CCA choice at 640A cold cranking, or the poverty spec 027 at 480A CCA, I would go for the 096 but check with a tape measure that the dimensions fit. Under £90 from ECP.

This is based on a 2007 M59 1.6 HDi so should be the one(s) you need.

Have a search in Google, the dimensions will be in there somewhere on ECP or Halfrauds etc

[saskak]

It should read 14.4V when running, 15.4V is too high. (unless that was a typo) - the simplest thing is try another battery. It takes no time at all to rule out, unlike the starter which is a way bigger job to change and much harder to verify.

When it is warm, is it not the case that it starts so quickly that you never notice the cranking speed and it just "seems" to start ok? (since the oil is now warm and thin). Overnight cold means it takes a fair lump of current to swing that diesel engine over. Once it's warm, it needs way less power to crank it.

I don't know if you can get a battery from someplace like Halfords and return it if that isn't the issue, or just take the hit and buy a new battery - it will never ever be a bad move to have a new one.

And I agree with the statement that a bad starter is always bad. It usually wouldn't improve after being used. There are places which can actually load-test the battery, like kwik-fit or a garage nearby. That could be a starting point.

I have this bad-boy, so never need to guess if I have a potential battery issue: (hook up, connect with Bluetooth from the phone and crank away, full battery testing in your hand at any time.)

https://www.amazon.co.uk/Battery-Crankin...B0BHQYS6WZ

Apologies for hijacking the thread, @Zion do you know if the topdon is actually doing a load test with actual resistance or is it from calculations?

[cancunia]

Slow cranking may well be due to the starter motor brushes. Exactly the same thing happened with my '05 2.0 HDi. There are a few threads on this & opinion varies around getting a new high duty starter or replacing the brushes on the old one.

[Guanock]

Worth checking the battery and starter cable connections. Also check, with a multimeter, the earth bonding from battery to body and engine.

Geoff

[Sol]

It should read 14.4V when running, 15.4V is too high. (unless that was a typo) - the simplest thing is try another battery. It takes no time at all to rule out, unlike the starter which is a way bigger job to change and much harder to verify.

When it is warm, is it not the case that it starts so quickly that you never notice the cranking speed and it just "seems" to start ok? (since the oil is now warm and thin). Overnight cold means it takes a fair lump of current to swing that diesel engine over. Once it's warm, it needs way less power to crank it.

I don't know if you can get a battery from someplace like Halfords and return it if that isn't the issue, or just take the hit and buy a new battery - it will never ever be a bad move to have a new one.

And I agree with the statement that a bad starter is always bad. It usually wouldn't improve after being used. There are places which can actually load-test the battery, like kwik-fit or a garage nearby. That could be a starting point.

I have this bad-boy, so never need to guess if I have a potential battery issue: (hook up, connect with Bluetooth from the phone and crank away, full battery testing in your hand at any time.)

https://www.amazon.co.uk/Battery-Crankin...B0BHQYS6WZ

Apologies for hijacking the thread, @Zion do you know if the topdon is actually doing a load test with actual resistance or is it from calculations?

It uses a shunt coil mate, from what I can tell in the video blurb. It can measure volt drop and that is directly convertible to current capacity. I also expect it can measure the battery internal resistance and again if you have two terms of Ohms law, then you can calculate the third and by calculation is still correct.

Ohms law is absolute.

The shunt will be in a Wheatstone bridge, you measure the unknown resistance by using a known voltage and the current in the bridge is used to calculate the unknown impedance. The battery supplies the voltage, the bridge measures the internal impedance. From that you can calculate the maximum current which can flow.

Basically you put an impedance across the battery. A current flows which is the product of the load impedance and the battery internal impedance in series. Added together, they define the total circuit resistance R, and we get current from V/R=I

R = R1 + R2 (battery impedance + shunt impedance)

The current in the resistor R2 (in the tester) can be measured and used to calculate the internal resistance of the battery. Once it has the load resistor current and the battery voltage, the rest is calculated: since it knows the load resistor value, it measures the voltage and current, then the calculation shows another resistance exists in the circuit. This is the battery internal resistance. V/I=R.

From that you can calculate the battery output capacity in amps.

Hope this makes sense. It's late and I'm tired lol.

[Garymallissa]

Slow cranking may well be due to the starter motor brushes. Exactly the same thing happened with my '05 2.0 HDi. There are a few threads on this & opinion varies around getting a new high duty starter or replacing the brushes on the old one.

I wasn’t sure where to go first, may try battery then if no good go for a starter. Thanks

[Garymallissa]

Worth checking the battery and starter cable connections. Also check, with a multimeter, the earth bonding from battery to body and engine.

Geoff

Thank you, will check this