318iS starting problem

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MrWhite
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Post Fri Sep 25, 2009 9:16 pm

I hope somebody can help me, the car won't turn over.

Battery is good (fixed that problem last week)
I turn the key and the starter solenoid goes clunk but the motor won't turn. I did a search for other threads:
I've tried the pin 11 & 14 test - exactly the same thing happens.

I tried rocking the car in gear incase the pinion wasn't engaging, still no joy.

It was running fine half an hour ago, I switched it off went indoors for 2 minutes, came out and it won't start.

Is my starter motor buggered or is it something else?

engine is M42 and the car has an alarm system (old dealer fitted) although the alarm is currently disarmed, if that helps

TIA
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MrWhite
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Post Fri Sep 25, 2009 9:30 pm

Having another try and I do notice that when I turn the ignition on I no longer hear the fuel pump charging.
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Brianmoooore
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Post Sat Sep 26, 2009 12:53 am

First, check the voltage across the battery, then check for a voltage between the battery negative terminal and the engine block/cylinder head when trying to start the engine.
MrWhite
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Post Sat Sep 26, 2009 11:01 am

Brian,

Voltage across battery is 12.35V

Voltage from battery neg to block/head (tried a few places) when trying to start is 0.028V
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Brianmoooore
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Post Sat Sep 26, 2009 11:09 am

Sounds like you may be in need of a new starter motor then!(Or more accurately, the solenoid on it.)
One last thing you can check is that there isn't a poor connection at one of the 13mm nuts on the solenoid - turned out to be all that was wrong with one I was about to change a couple of months ago.
E30Mark
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Post Sat Sep 26, 2009 11:16 am

If it's not electrical, then try taking the spark plugs and checking the cylinders aren't full of coolant :(
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MrWhite
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Post Sat Sep 26, 2009 11:36 am

Well, I loosened both the 13mm nuts and gave the connections a clean, bolted it back up and it starts again!
The car got a good wash yesterday and water always finds its way into the engine bay, could this have caused the problem? Damp connections? They were a little corroded.

I also noticed that the cable coming from the uppermost 10mm nut on the starter has been joined and taped up at some point. Would a poor connection here cause the problem I was having?
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Brianmoooore
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Post Sat Sep 26, 2009 11:55 am

No power is fed from the solenoid to the fusebox on facelift E30s, willnz - fusebox power is from one of the smaller leads attached to the battery + clamp!
There is a wire that goes on from the outer 13mm nut to the alternator; the 10mm nut should be the black/yellow start signal from the ignition switch, and the 8mm nut should be the connection for the unloader relays.
The problem you've found is as a result of long term corrosion, rather than recent damp, plus the terminal probably wasn't tightened properly. Mine wasn't!
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Post Sat Sep 26, 2009 12:08 pm

It seems to have done the trick for now anyway.

Thanks for your simple, methodical fault finding tips Brian. Without them I'd still be running around in a panic and probably have taken half the engine bay out in preparation for changing a fully functional starter motor.

:D
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Brianmoooore
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Post Sat Sep 26, 2009 9:18 pm

willnz wrote:Ha! I didnt read the post properly, I half read it ....... Pays to read the whole post properly !! :o: :o: :o:
Something I'm often guilty of as well! (Such as the the alarm wires question from a couple of days ago!)