URGENT HELP PLEASE- BMW 840 WILL NOT START UP
URGENT HELP PLEASE- BMW 840 WILL NOT START UP
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Discussion

Vvroom

Original Poster:

1,170 posts

220 months

Sunday 7th June 2009
quotequote all
I'm a man on the edge,

6 months ago I bought an 840ci to tart up a bit and take to Le Mans (I set off on Wed 10th June). It's not my daily driver. Last night I turned the engine over and it fired up first time. It was running for 2 mins or so and then I cut the power while I applied some le mans decals. About 30mins later, I tried to fire it up again and nothing. All the electrics work- new batteries were fitted about 2 months ago. When the key it turned fully there is a 'click' under the bonnet but nothing else- doesn't even try to turn over.

I waited an hour or so, fearing I may have somehow flooded it, but still nothing.

Any ideas/suggestions would be greatly appreciated.

Wacky Racer

41,363 posts

277 months

Sunday 7th June 2009
quotequote all
Try giving the starter motor a few gentle taps with the wooden shaft of a hammer, it may have stuck.......

Also ensure all battery connections are tight and not corroded.......and there is a good earth connection.

Can't be anything too serious can it?

Nigel Worc's

8,121 posts

218 months

Sunday 7th June 2009
quotequote all
I am a beemer man, but I don't know the 840.

The click you can here will probably be the solanoid coming in, when this happenes do all the lights go dim (dash lights etc) or does everything stay the same, just the engine doesn't turn over ?

If the later, depending on your type of starter motor, I'd be looking to check two things.

Is there any voltage on the big "power" lead at the solanoid ... if not, why not (check any links/fuses/connectors etc) ?

If there is power to the solanoid, when the click happens, does power come out of the solanoid, on the lead/link going to the starter motor ?

If it does, you may have an open circuit starter motor (brushes, windings, etc)

If it doesn't, you may have a faulty solanoid.

I don't know how much knowledge you have of electrical items, but there is an awful lot of "current" available at this point on a car, so unless you are reasonably happy with electrical circuits, leave it alone, and call the RAC/AA or whoever.

koenig d

127 posts

210 months

Sunday 7th June 2009
quotequote all
recharge the baterys.I don't know very much about the 840's but my 850 had simular probs the v12 has two baterys in the boot. there is a low voltage protection program on these cars.the obc can give you the voltage. i think it's 100+10 at the same time then 19. best of look

Chester Drawers

402 posts

228 months

Sunday 7th June 2009
quotequote all
koenig d said:
recharge the baterys.I don't know very much about the 840's but my 850 had simular probs the v12 has two baterys in the boot. there is a low voltage protection program on these cars.the obc can give you the voltage. i think it's 100+10 at the same time then 19. best of look
+1

Even if the batteries are quite new, they lose quite a lot of power with the car just standing around. If you started it once that may have used the last gasp of power reserve left in the batteries. I'd check the voltage reading from the plus pole in the engine bay (under the little black cap marked with a red "+") - if the reading is less than 14V wou'll probably have trouble starting the car. I had the same trouble with my M73 850, charging the batteries for a few hours fixed the problem.
If the batteries are fine then it could be a stuck solenoid - try tapping the side of it with something - carefully! don't belt ten kinds of $hit out it.

blaineuk

2,615 posts

277 months

Sunday 7th June 2009
quotequote all
sounds like flat batteries to me

EightFortySeeEye

52 posts

213 months

Sunday 7th June 2009
quotequote all
these cars take alot of power when being started up and if you had the car not being run on a regular basis for 2 months and then did that it is most likely that you took out enough charge from the battery to prevent it from starting up, but theres enough left to have the electrics working

that was a problem with these cars they just draw too much power from the batteries

all you need to do is to charge up your battery and try and run it on a fairly regular basis otherwise eventually after a few charge ups your just gonna have to buy new batteries

ive had this issue a few times before

it can be annoying but you get used to it and expect it when you stop driving the car regularly



Edited by EightFortySeeEye on Sunday 7th June 20:46

Nigel Worc's

8,121 posts

218 months

Monday 8th June 2009
quotequote all
Would one of those "solar charger thingies" help in these situations ?

Vvroom

Original Poster:

1,170 posts

220 months

Monday 8th June 2009
quotequote all
Panic over- 8 series back on top form following a jump start and a hundred mile blast along the motorway.

Got some interesting looks as well as it's all stickered up for le mans.

Thanks to everyone who responded.


Vvroom

Original Poster:

1,170 posts

220 months

Monday 8th June 2009
quotequote all
Panic over- 8 series back on top form following a jump start and a hundred mile blast along the motorway.

Got some interesting looks as well as it's all stickered up for le mans.

Thanks to everyone who responded.


Eggle

3,609 posts

266 months

Tuesday 9th June 2009
quotequote all
Great news.

Eggle

3,609 posts

266 months

Tuesday 9th June 2009
quotequote all
Great news.