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Slow Cranking

It sounds fine at that voltage to me ..

Try checking it under a load to be sure so lights on main beam on heated seats and anything else you have and then see what the voltage is at the battery .. needs to be 13v or higher .

I would normally check at the alternator and then at the battery to see what the difference is .. this will give you an idea of any resistance in the power line .. 0.6 volts and higher is a problem.

Checking at the alternator isnt easy though so just try my first check .

Earth lead in the picture .. o/s/r ( Off Side Rear or right side of the car at the back ).
 
Is the slow cranking only when hot?
 
No slow cranking is all the time.

I've done some more investigation.

I don't believe it's the battery as it's been replaced for new one.

I don't believe it's the Alternator as still did it with a brand new fully charged battery and the alternator is charging the battery.

It's not a corroded earth strap as I've checked and no corrosion but cleaned anyway.

It's not the power pin as I've checked and no corrosion plus cleaned anyway.

It's not the +'ve cable joint under the car, on the side of the gearbox as again checked and cleaned anyway.

Ran out of time to check the cabling up by the starter but that's my next place to check.

I'm starting to think possibly starter motor is on its way out, but strange as it's done this for at least 8 months and if it was failing surely it would have failed by now.

Does anyone know can a starter motor loose performance if the battery and cabling are all checked good ?

Any other suggestions?
 
Slow cranking

I didn't realise I had slow cranking until I replaced the alternator-starter-battery cable earlier this year. I had the slow cranking problem when hot but since replacing the cable the cold cranking speed has also increased dramatically.

Cable replacement is a DIY job but fiddly. I did post a few notes on here when I did it.

Darren.
 
Slow crank

Sorry, just re-read, you've already replaced it.
 
As with all problems we eliminate what we can and what we are left with is the fault .. either that or there is no fault .

Everyone here has listed what to check .. you tick it off and then move on .

I would like to confirm you have actually replaced the lead from the starter / alternator to the gearbox connection as your first and last post seems to make that a little unclear .. and this is the normal cause of slow cranking .

Soo what do we have .. not battery , leads , alternator , earth straps ..

As long as these have all been checked then you are left with a startermotor or there isnt a fault .

A starter has a solinoid .. its basically 2 bolts with a copper bar that jams against them to pass the current to the motor it self .. this can end up with burning and cause a resistance .. hence a slow crank as not enough current gets past the burnt contacts to give a faster crank ... high resistance.

If thats all we are left with after the checks then thats the fault .. but once again .. thats if there is a fault (i cant see the car ) and if everything else has been checked .

Logical .. and now im praying that it IS the startermotor :)
 
No 22 but thats a wierd picture .. lead from the starter to the alternaor and to the connection on the gearbox basically.

manual can be done in situe .. Tip and its engine out .
 
Thanks,

I have slow cranking and have done the power pin mod converting to a threaded stud which helped a little.

Going to replace the cable next,

2 part no's listed:

22

99760703200

wiring harness starter generator

I249

£116.57


1
22

99760703100

wiring harness starter generator

I480

£109.84
 
Thanks I've already done that with no improvement unfortunatelt but thanks for the suggestion.

How long would you say the delay is if any, from turning the key to engine running?

My wife's BMW is instant, my 997.1 is about 1 to 2 seconds delay.
 
deMort said:
As with all problems we eliminate what we can and what we are left with is the fault .. either that or there is no fault .

Everyone here has listed what to check .. you tick it off and then move on .

I would like to confirm you have actually replaced the lead from the starter / alternator to the gearbox connection as your first and last post seems to make that a little unclear .. and this is the normal cause of slow cranking .

Soo what do we have .. not battery , leads , alternator , earth straps ..

As long as these have all been checked then you are left with a startermotor or there isnt a fault .

A starter has a solinoid .. its basically 2 bolts with a copper bar that jams against them to pass the current to the motor it self .. this can end up with burning and cause a resistance .. hence a slow crank as not enough current gets past the burnt contacts to give a faster crank ... high resistance.

If thats all we are left with after the checks then thats the fault .. but once again .. thats if there is a fault (i cant see the car ) and if everything else has been checked .

Logical .. and now im praying that it IS the startermotor :)

Sorry for the confusion. It was replaced 8 months ago by a dealer. I was going to check nothing has changed or it suffered corrosion in the I months its been on.

Some very helpful advice which is appreciated. Thanks
 
Steve997 said:
Thanks I've already done that with no improvement unfortunatelt but thanks for the suggestion.

How long would you say the delay is if any, from turning the key to engine running?

My wife's BMW is instant, my 997.1 is about 1 to 2 seconds delay.

On the 997.2 it's a short delay whilst it turns over a couple of times, then fires.
 
Thanks Magic

I'm starting to think it might be typical and normal after you posting that.

What put the thought in my mind was an OPC dealer who did a Health Check said it was lazy starting and compared to my wife's 3 series diesel it is.

It's always took a second or 2 to fire so maybe that's just how the 997 engine is.
 

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