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Does this sound like a healthy battery?
AndyW - 4/10/13 at 10:24 AM

I Guys,

Still trying to get to the bottom of the hot start issue.

Battery as it stands is 12.4v across the terminals.

On cranking 9.9v to 10.0v

Engine ticking over 13.4v

Engine revving at around 2000rpm is 13.5v steady.

On cold start, car been sitting for a day or so, starts first time. Go for drive (short distance about 5 miles) or leave car ticking over whilst checking hoses etc, gets up to temp, fan kicks in and out all ok.

Stop the engine, then try and re-start and it barely turns over, as if trying to start with a flat battery.

Let everything cool down and it starts fine.

I don't want to start replacing things here there and everywhere, would rather a methodical way of checking things out to see what is happening. Another member had similar issues and replaced starter (along with other things), but just wanted to see if anything else is worth checking first, as I can't understand how a dodgy starter would create these symptoms.

I will check earths, etc but could do with where to start really. At the moment I don't want to go out too far, as if I need petrol the thing wont start again.

Any help as always appreciated.

Ta

Andy

coozer - 4/10/13 at 10:43 AM

Sounds like the engine heat is causing a short somewhere. Maybe the windings in the starter, or relay if fitted, or a break somewhere in the wiring insulation allowing the volts to escape.

I had a similar experience (but all the time) where the battery measured fine but applying the starter the load caused a short inside the battery.

steve m - 4/10/13 at 10:57 AM

Ive had similar problems on my 7, and it got so bad I was petrified of driving it, in case it stalled, as hot it would barely turn over
and it was not a timing issue (crossflow)

I changed the starter motor, no difference
checked the wiring loom, no difference
installed a cut off switch, no difference

changed the battery, to one that would jump start the Titanic, works every time, and spins the engine so fast it registers on the rev counter !!

the old battery is 2 years old, and never worked properly but I can not find the receipt, so lost about £50

Steve

steve m - 4/10/13 at 11:00 AM

The only other thing, that I did do, was to connect the - from battery to chassis and engine, so two separate wires
and ive installed another alternator to chassis wire as well, "belt and braces"
only as I had them in stock
ALL the other main feed battery wiring is less than a year old,

Steve

britishtrident - 4/10/13 at 11:04 AM

Root cause is too much ignition advance at cranking speeds, the engine is trying to start backwards fighting against the starter.

stevebubs - 4/10/13 at 11:04 AM

I had similar with my zetec; had to back off the timing when cranking. When I did that, the problem went away.

AndyW - 4/10/13 at 11:48 AM

quote:
Originally posted by britishtrident
Root cause is too much ignition advance at cranking speeds, the engine is trying to start backwards fighting against the starter.


I'm using a standard ecu so no ability to change , all pre-set parameters.

AndyW - 4/10/13 at 11:50 AM

quote:
Originally posted by steve m
The only other thing, that I did do, was to connect the - from battery to chassis and engine, so two separate wires
and ive installed another alternator to chassis wire as well, "belt and braces"
only as I had them in stock
ALL the other main feed battery wiring is less than a year old,

Steve


I have the battery - to chassis, and an engine - to chassis, 2 separate cables, so will also check those out.

steve m - 4/10/13 at 11:53 AM

Mine was also not timing, as even with the coil disconnected, it would not turn over fast enough

Peteff - 4/10/13 at 12:20 PM

12.4v is not a healthy battery it wants to be over 12.6v with the engine off.

stevebubs - 4/10/13 at 12:23 PM

quote:
Originally posted by AndyW
quote:
Originally posted by britishtrident
Root cause is too much ignition advance at cranking speeds, the engine is trying to start backwards fighting against the starter.


I'm using a standard ecu so no ability to change , all pre-set parameters.


In which case, does adding extra current using jump leads to the tintop help?

AndyW - 4/10/13 at 12:43 PM

quote:
Originally posted by stevebubs
quote:
Originally posted by AndyW
quote:
Originally posted by britishtrident
Root cause is too much ignition advance at cranking speeds, the engine is trying to start backwards fighting against the starter.


I'm using a standard ecu so no ability to change , all pre-set parameters.


In which case, does adding extra current using jump leads to the tintop help?


Yes, as soon as I add either jumper cables or a starter pack, fires right up.

AndyW - 4/10/13 at 12:44 PM

Could it be that due to the amount of testing the car had recently, and not actually driving, the battery could just need a dam good charge???

stevebubs - 4/10/13 at 12:48 PM

then I would definitely point the finger at the battery not being able to provide enough starting current.

You could try giving it a good charge / using an Accumate but I would suspect you're original thoughts are right and it's on the way out....

[Edited on 4/10/13 by stevebubs]

[Edited on 4/10/13 by stevebubs]

Davegtst - 4/10/13 at 01:34 PM

Drive it down to halfrauds. They should test foc for you.

stevebubs - 4/10/13 at 03:51 PM

quote:
Originally posted by Davegtst
Drive it down to halfrauds. They should test foc for you.


Their reputation for getting it right isn't great....

Davegtst - 4/10/13 at 03:57 PM

Maybe not but they do have battery testing tools. Have you got a heat shield around the starter?

britishtrident - 4/10/13 at 05:11 PM

quote:
Originally posted by AndyW
quote:
Originally posted by britishtrident
Root cause is too much ignition advance at cranking speeds, the engine is trying to start backwards fighting against the starter.


I'm using a standard ecu so no ability to change , all pre-set parameters.


You have the full Zetec system then, usually excessive ignition advance occurs on Zetecs that have been fitted using the CVH ESC ignition module.
The CVH ESC module gives excessive ignition advance when fitted to a Zetec because CVH engine has combustion chamber shape with very slow combustion to more modern engines like the Zetec.