Alternator shot but what else ?
Alternator shot but what else ?
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richo_i

Original Poster:

361 posts

244 months

Monday 13th November 2006
quotequote all
Took MOH out for a short blast yesterday after she had stood for 2 weeks she started without a problem let her warm up for 10 mins and set off, As is the norm she was missing at about 4000 rpm but by 4500 going like a Boeing arrived at our destination switched her of while the other half went to get the Sunday veg . Went to restart and she would hardly turn over called a mate for a jump start and she fired straight off set off home with voltage meter reading 10 and missing from 3500 rpm up after 5 miles voltage gauge showing 8 and missing from 2000 up by the time I got home voltage gauge showing next to nothing MOH running like a pig missing all the time and almost dieing on gear changes pulled up at home she cut out and was completely dead .
I take it that my alternator is shot but would that cause the ruff running? Or do I have other problems as well?

NHyde

1,427 posts

277 months

Monday 13th November 2006
quotequote all
May not be the alternator.

Do you get an ignition light when you switch on ? If you don't the exciter circuit is not live, and you are running on the battery .

Just a thought .

dickymint

29,078 posts

287 months

Monday 13th November 2006
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Sorry to hear M0H is a tad poorly. Had similar once before. Turned out to my embarrasment that it was just the fan belt loose (seemed ok to me at the time but needed to be tighter than i thought). Also try a new battery as this could now be knackered. PS yes i know - i still haven't posted you the alarm blipper

dickymint

29,078 posts

287 months

Monday 13th November 2006
quotequote all
NHyde said:
May not be the alternator.

Do you get an ignition light when you switch on ? If you don't the exciter circuit is not live, and you are running on the battery .

Just a thought .


Hiya Neil, quite right there. Also is the ignition light on without the key in the ignition? this would tell you that the resistor pack in the alternator is duff.

NHyde

1,427 posts

277 months

Monday 13th November 2006
quotequote all
Hiya Dicky , is there much Wedge representation on the 26th ?

adam quantrill

11,679 posts

271 months

Monday 13th November 2006
quotequote all
I had a wire snap just next to the alternator - similar symptoms and caused one of only 3 recoveries I needed to have in a wedge in 15 years of wedging.

If the alternator itself has packed in, 2nd hand SDi ones work fine, or else a recon one won't be too much. I tend to try fixing mine first though, quite often just cleaning off the commutator with some sandpaper sorts it out.

jchase

572 posts

288 months

Tuesday 14th November 2006
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If the alternator is old, the rotor will usually have become magnetised to some extent, and won't need the exciter circuit.

The flapper ECU does not appear to correct the injection time for battery voltage - which most modern ECUs do. Injectors (The old lucas ones) usually take around 1ms to switch on at 12v, and it changes by around 0.1 ms/ volt - which when you consider they are only open for around 1ms at idle its not surprising the car ran rough! under full load they are on for sommit like 10ms, so not such an issue. - i bet your plugs are nice and clean from the heat now though!!

-jim

GV

2,366 posts

253 months

Wednesday 15th November 2006
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I would check your Earth wiring and your fan belt. It may not be a faulty alternator if its been working ok before the car stood for a while.