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Discussion Starter · #1 ·
I've been trying to sort out why my 2.5 has been hard to start, it seems like a flat battery but on the third attempt it usually spins ok.
Except when it's hot when it just keeps up it's flat battery impression.

I read about somebody in South Africa who said his starter played up when it got hot so I've been checking that out. Not an easy job moving the exhaust out of the way.

Before I started all this I had the battery load tested, they said it was putting out 900CCA but it still had to be jump started.

The cables only show a .6 volt drop but the battery drops to 9 volts when it does start and 7 to 6 volts when it won't start.

Can someone enlighten me why it can show 900 CCA but also drop to 9 or 6 volts?
 

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Splash out on a new battery ????

You have just described all the symptoms of a bad battery ????

And for peace of mind, while you're in the battery box, check all the connectors and the main battery wiring
 

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It could also be a starter motor issue dragging more than the 900 Amps, my V6 had a similar issue, that was resolved by replacing the starter with an upgraded one.
 

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Discussion Starter · #4 ·
Splash out on a new battery ????

You have just described all the symptoms of a bad battery ????

And for peace of mind, while you're in the battery box, check all the connectors and the main battery wiring
Yeah, I suspect the load test wasn't any good.
Also thinking of getting a super capacitor starting battery to add to the battery.
The super caps do the starting and the battery does the rest of the battery stuff.
 

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Discussion Starter · #5 ·
It could also be a starter motor issue dragging more than the 900 Amps, my V6 had a similar issue, that was resolved by replacing the starter with an upgraded one.
I did think of that, starter is so hard to get to but it's exposed now.

Thing is, it starts ok from a jump.
I suspect that the load test wasn't any good.
 

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Discussion Starter · #6 ·
Update:
Got a new battery, 800 CCA, same thing exactly.
When it's cold it starts right up, when it's hot it acts like a flat battery.
After 3 or 4 goes it will start then start ok every time after that that until next time.
New battery tested perfect.
Old 900 CCA battery tested at 560CCA which should have been enough.
Both tests at 28 degrees C.
Cable connections are good, voltage drop on cables max .6 volts while cranking.
 

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Update:
Got a new battery, 800 CCA, same thing exactly.
When it's cold it starts right up, when it's hot it acts like a flat battery.
After 3 or 4 goes it will start then start ok every time after that that until next time.
New battery tested perfect.
Old 900 CCA battery tested at 560CCA which should have been enough.
Both tests at 28 degrees C.
Cable connections are good, voltage drop on cables max .6 volts while cranking.
I'd go with the starter motor failing when the engines hot due to some expansion effects on it from the heat
 

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Discussion Starter · #8 ·
I'd go with the starter motor failing when the engines hot due to some expansion effects on it from the heat
That's where I'm at now.
The starter is a dick to get to.

With the new battery it starts most times but not always.
 

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Probably the solenoid if the motor itself spins freely when it works. Probably sticking when hot and not closing the heavy duty contactor correctly
 

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Thanks for posting up the cause
.... it always helps others to see the end result.

Did you have your starter refurbed or replace it with a new one ?
 
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