Screw size. Voltage stabilizer

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ve6sh

Member
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10
I am still fighting with my non functioning fuel gauge on my 1973 Series 3. Replaced the sending unit and it worked for a day! Stopped working and tested the voltage from the stabilizer -5v using a peak reading meter. Replaced the stabilizer ( a pain to remove!) but in the process I lost the screw that fixes the stabilizer to the rear of the speedo. Any idea what size it is?

I temporarily grounded the stabilizer and now the gauges work (Fuel and temp) so that was the issue. I would like to fix the stabilizer where it is supposed to be though.

The gauge reads low (3/4 for a full tank). Not sure if that is a float issue or wiring.
 
I don't know about the screw, and the parts manual is no help, but, I would try BA sizes first.

For the low reading, a high resistance connection anywhere in the circuit could cause this. A poor connection between the tank sender and earth, a poor connection at the large multi-plug by the steering box, etc, etc
 
I am still fighting with my non functioning fuel gauge on my 1973 Series 3. Replaced the sending unit and it worked for a day! Stopped working and tested the voltage from the stabilizer -5v using a peak reading meter. Replaced the stabilizer ( a pain to remove!) but in the process I lost the screw that fixes the stabilizer to the rear of the speedo. Any idea what size it is?

I temporarily grounded the stabilizer and now the gauges work (Fuel and temp) so that was the issue. I would like to fix the stabilizer where it is supposed to be though.

The gauge reads low (3/4 for a full tank). Not sure if that is a float issue or wiring.
Did you by any chance work out what size screw it was?
 
Did you by any chance work out what size screw it was?
M4 fits slightly loosely so 2BA . The screw dia when measured "on the thread" is 4mm ( 0.15") and 5/16th long. I don't have any BA screws on the shelf at all so I can't be 100% sure it's even BA but considering an M4 fits its highly likely.
 

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M4 fits slightly loosely so 2BA . The screw dia when measured "on the thread" is 4mm ( 0.15") and 5/16th long. I don't have any BA screws on the shelf at all so I can't be 100% sure it's even BA but considering an M4 fits its highly likely.
Thanks Phil - I ended up just going down with a mix of M bolts and yes an M4 works albeit loosely!
 
On another rote, both the auxiliary gauges aren't working. I fitted a new voltage stabiliser to no success. Reckon a dud stabiliser or both senders are gone? (or anything else?!)
 
It's been over 40 years since I messed with these on a Triumph GT6 . Same arrangement of Smith's gauges with an identical voltage stabiliser. If I remember correctly the stabiliser should give 5 volt DC. It'll be another couple of months before I have to deal with the setup on my Series 3. I'm already contemplating replacing the stabiliser internal parts with a suitably rated IC (7805)
 
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