28 replies to this topic

[mister bridger]

from the pictures you have the newer sender unit and the newer speedo housing, there is no sign of the voltage stabiliser unit there, it should be at the top.
in my opinion if it was working fine before, then its the main + cable is earthing out or the sender unit is stuck in the full position.

So presumably I need a replacement newer gauge - and a voltage stabiliser? Sender unlikely to be stuck on full as it has had very little fuel in for ages

[dklawson]

Stormintrooper, if you did not find the voltage stabilizer then you are quite likely to have the Nippon-Seiki gauges as they bury the chip deep inside somewhere. Your gauges will not read anywhere close to correct without it. If it were removed, they wouldn't read at all. The link below should show the back of the Nippon-Seiki gauges... no stabilizer visible.
http://www.greatbrit...l...ppon&cat=56


Mister Bridger... I am SO sorry. Yes, I meant the screws securing the fuel gauge to the speedometer NOT the two studs used to adjust the calibration of the early gauge. You now have a serious problem to deal with. Minridge's observations are also correct that there is seemingly contradictory information in your photographs. The sender is the bayonet mount type but the back of your gauge is clearly the early type. I have been told that there are a handful of transitional cars that have a bayonet mount sending unit with the early sending unit calibration. It appears you MUST have one of those and this would be an extremely rare thing. Your car and mine were built at almost exactly the same time but mine came to me with mismatched gauges that never worked. (Bolt on sending unit and later type gauge).

My advice is....
1) Buy a later sending unit and a later fuel gauge (used is OK). Both will fit the hardware you have now (which is fortunate as most early gauge replacements require replacing the fuel tank to allow use of the later sending unit).
2) Start a new thread on this board asking about the voltage stabilizer. Yes, you will need to add one to your car but the old electro/mechanical ones won't fit your speedo and they are problematic anyway. Several guys on this board now make their own solid state version and will sell you one (and they should do it cheap!). The simplest form is as shown in my friend Wes's JPG link below.
http://www.adocars.c...mages/v-reg.jpg
You can add that anywhere on the back of your speedo and use its 10V output to power the fuel gauge.
3) Whatever you do... DO NOT throw out the broken fuel gauge and suspect sending unit. SAVE THEM and/or sell them to someone restoring an early car. The fuel gauge can be repaired but will likely cost more than it is worth to you compared to buying a new/used fuel gauge and sending unit.

If you feel like tinkering, make your own voltage stabilizer as shown in the JPG above. If you want additional reading on the voltage stabilizer and/or the early gauge system you can read about them in these two documents I put together some years ago.
http://home.mindspri...ldFuelGauge.pdf
http://home.mindspri...eStabilizer.pdf

Please give this some thought and let us know what you decide to do.

EDIT: I did not think to ask... is your car still positive earth or have you converted to negative? IF your car is still positive earth you cannot use the solid-state voltage stabilizers I mentioned above. You will either need to find an original Smiths voltage stabilizer (let us know if that's necessary) or you would have to convert to negative earth to use a solid-state stabilizer.

Edited by dklawson, 13 February 2009 - 03:54 PM.

[miniboo]

I have an old gauge in the garage that you can have the fuel gauge off if you want. it is the one with the 2 cork disks so is a later type gaugeaccording to DK

[stormintrooper]

i do have one of those nippon whatevers well the speedo is 100% mechanical...the middle clock on the inside only has the bi-metallic bits in it so im only left to guess that its part of tacho as theres plenty of electronic parts built into it with a circuit board....would this be the "chip" your referring to?

or is it hidden within the plastic? because i got it fully dismantled infront of me right now and still do not see a chip unless its part of the tacho

Edited by stormintrooper, 13 February 2009 - 04:09 PM.

[mister bridger]

EDIT: I did not think to ask... is your car still positive earth or have you converted to negative? IF your car is still positive earth you cannot use the solid-state voltage stabilizers I mentioned above. You will either need to find an original Smiths voltage stabilizer (let us know if that's necessary) or you would have to convert to negative earth to use a solid-state stabilizer.

Car has been converted (not by me) to negative earth thankfully. Alas electrics are a bit of a closed book to me so will not be attempting to make one!

[dklawson]

Car has been converted (not by me) to negative earth thankfully. Alas electrics are a bit of a closed book to me so will not be attempting to make one!

I understand. However, at least take a moment to look at the JPG link I posted for my friends Wes' simplified version.
http://www.adocars.c...mages/v-reg.jpg
All you have to do with that one is buy the chip, solder on three wires (with spade lugs) and cover the joints with heat shrink tubing. It's an absolute piece of cake.

If no one offers up a home-made solid state one for you, Moss USA has a generic solid state stabilizer packaged in a Smiths look-alike housing (Moss part numbers 131-555 negative earth, 131-556 positive earth). I don't know if they sell it in Europe. Their product is shown in the JPG link below.
http://www.mgbsource...ize/131-556.jpg

[mister bridger]

thanks for your help - after endless probs with carbs and manifolds etc my priority now is just to get MOT'd and on the road. I'll make do with a dipstick and keeping tank full until I can get the bits I need and then take it to an auto electrician.

[Whatty]

DKLawson -

Sir you are to be applauded for your patience and the generous spirit with which you provide all this information ...Thank you!

My '69 Morris is showing the same symptoms BUT as its only a Sunday driver I don't worry too much about it. Its great to actually understand what may be occurring even if I can't fix it myself!

Yours, always a full tank in NJ
Whatty.

Edited by Whatty, 13 February 2009 - 05:45 PM.

[dklawson]

Well thank you Whatty. I enjoy the people on this board and I am slowly learning more about the later cars from them.

The gauge system in your '69 will be the later type as described in my voltage stabilizer PDF. It will behave differently than the early system Mister Bridger's car has. If you have any questions when you start trying to sort yours out don't hesitate to ask questions.

Regardless of where you are in NJ, I hope your weather is warm and dry so you can enjoy driving your car.

[Jupitus]

Just FYI, Voltage stabiliser (solid state) £5 posted

[dklawson]

Thanks Jupitus. I knew I could count on you but I didn't want to start dropping names!

[mister bridger]

I have sent Jupitus a pm

[Jupitus]

No worries Doug, and PM replied, Mister B. At £5 posted these make me nothing at all, but it does keep our beloveds on the road

[Phaeton]

No worries Doug, and PM replied, Mister B. At £5 posted these make me nothing at all, but it does keep our beloveds on the road

Tis a good price, I bought mine off Fleecebay & I'm sure it was nearly £10 delivered. Must say they are much better then the old style, but I suppose they ought to be really.

Alan...