Swinging Tacho
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Swinging Tacho
After accelerating the tacho needle oscillates by +/- 1000rpm approx. before settling down to the new speed. Is this a symptom of anything? Everything else is fine. A beautiful Winter's morning for a drive around West Cork today BTW - life is peachy sometimes.
Garrett Dee
1973 911 S Targa
1973 911 S Targa
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I had a similar problem occur on my '79 SC. First the tacho needle swung all over the place, later the chraging light came on but not very bright. Eventually turned out to be failing, but not yet failed, alternator. Took ages to confirm because it appeared to be putting out just enough charge.
Hope this helps
Ian
Hope this helps
Ian
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I have seen the bouncing tacho from both points gaps set incorrectly and also from low charge voltage. If you have a voltmeter, check the voltage across the battery with the engine on a "fast tickover" approx 2500 rpm, should be 14V ish. This should give an indication of a alternator problem.
Check the points gap anyway , just for good measure.
Enjoy
Tim
Check the points gap anyway , just for good measure.
Enjoy
Tim
Tim Bennett
RHD Targa 2.2T EFI, Triumph ITB's, EDIS and Megasquirt.
"Old enough to know what's right and young enough not to choose it"
#1153
RHD Targa 2.2T EFI, Triumph ITB's, EDIS and Megasquirt.
"Old enough to know what's right and young enough not to choose it"
#1153
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As I have the same rev counter symptoms and a charge light that doesn't always go out straight away when I start her up, maybe it's time to start thinking alternator.
Mind you, I'll catch this with the engine rebuild...
Mind you, I'll catch this with the engine rebuild...
2006 RHD 997 Carrera (but DDK remains in my heart - also now no longer)
1972 LHD 2.4T with '73 2.4T CIS motor - gone to a new DDK home
1994 RHD 993 Carrera - gone!
1968 LHD 911L - was the Wife's but now in new hands
#1252
1972 LHD 2.4T with '73 2.4T CIS motor - gone to a new DDK home
1994 RHD 993 Carrera - gone!
1968 LHD 911L - was the Wife's but now in new hands
#1252
Not clear what Tacho u have, after along rebuild was one of the last things left to do on 72, 2.4 s ........................sent off for a refurb and has a new damper and all fine now , find a local instruments mender and u ll be fine ..................if its fittted with a damper in the first place
Thanks for all the replies.
I checked out the points and they're ok, 0.3mm gap and clean. alternator light does sometimes take a blip of the throttle to go out. Fan belt is possibly a bit loose - about 1" play midway between pulleys- is this right?
I'll get a DVM and check the voltage across the battery / alternator function next w/end.
The tacho is VDO/std issue I think
I checked out the points and they're ok, 0.3mm gap and clean. alternator light does sometimes take a blip of the throttle to go out. Fan belt is possibly a bit loose - about 1" play midway between pulleys- is this right?
I'll get a DVM and check the voltage across the battery / alternator function next w/end.
The tacho is VDO/std issue I think
Garrett Dee
1973 911 S Targa
1973 911 S Targa
VicVic Cohen wrote:Not clear what Tacho u have, after along rebuild was one of the last things left to do on 72, 2.4 s ........................sent off for a refurb and has a new damper and all fine now , find a local instruments mender and u ll be fine ..................if its fittted with a damper in the first place
Do you know where you can get refurbished Tachos from? I have the same problem on my 73 and it looks like its the Tacho unit rather than anything else.
Thanks.
Ian.