Bouncing Tach

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tanick
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Bouncing Tach

Post by tanick »

On the way home from the Fairmile last night I noticed my tach bouncing all over the place. Engine was running fine. I'm guessing its either the points need sorting or the Voltage regulator or coil is on its way out. According to the nice new gold sticker in the engine bay the alternator must match the voltage regulator. I've got a motorola alt. and a Marchal reg. Is this OK? Are the Marchal's easy to get, I can only see Bosch on most websites.

What with CLM 2 weeks away I'm tempted to just buy a coil and regulator now. The points are about 2 years/3,000 miles old. What are the chances its something simple? What should I do first?
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bjmullan
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Post by bjmullan »

The simple thing to do is check the points, it's the most obivous cause of your problem.
Brendan
1969 911T
2018 718 Boxster

Pray, hope and don't worry - Padre Pio
Gilbert '71 T
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Post by Gilbert '71 T »

happened to me Nick, and it was the points, well kind of....my points were held in by a self tapping screw which had lost its bite :evil: and the points were moving all the time, tapped a new thread, new M4 screw and the problem went away for a few days then it came back :(. so i eventually had to pull the distributor tap M5 in the hole and file out the slot in the points to accomodate the bigger screw, also used a star type washer with the screw and it's been fine ever since.

I'd start with a multimeter that has the dwell angle setting on it, hope this helps and it's something simple :)
Darren
71 911T with C3 motor
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hot66
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Post by hot66 »

mine bounces, and had done for nearly 3 years & through 2 major services :)
James

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1963 Honda C100 Supercub

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tanick
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Post by tanick »

Picked up a sealey timing light/dwell meter tonight as recommended by Nick Moss http://www.ddk-online.com/phpBB2/viewto ... ight=dwell but unfortunately didn't get to try it as my new plasma tv turned up 8)
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