Faulty Fuel Tank Sender / Fuel Gauge

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CharlieW
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Faulty Fuel Tank Sender / Fuel Gauge

Post by CharlieW »

Hi everyone.
Im brand new to the Forum and hoping for some advice. My Dad and I have a 1967 Minor 1000 Saloon which we are currently fixing up. Its SORN at the minute but we have big plans to get her back on the road...
We have an issue with the Fuel Tank Sender which appeared to be faulty - the fuel gauge never moved from the one position. After reading some of the previous posts and advice on here we tried the following:
*The old sender was disconnected from the electrical supply. We earthed the live lead to the car, switched on the ignition and the fuel gauge moved rapidly to full.
*We fitted a new fuel tank sender to the car with the float pointing due South - out of the boot of the car. The Tank had approx 2 gallons of Petrol, however the fuel gauge was reading under 1/4 full, which appeared to be too low. We tried fitting the new sender in different orientations which didnt work. I'm assuming there are maybe internal baffles in the tank. The only position we didnt try is with the float pointing North - towards the engine bay.
*We tried removing the sender (with live lead still attached), earthed it to the car and physically moved the sender float arm to the maximum position. Although the fuel gauge moved up it didnt go past half full. We refitted the old sender as a test which didnt give any of these results. Therefore we assumed the old sender is faulty and refitted the new one.
*Next we removed the speedo and earthed the terminals of the Voltage Regulator to the dash. After switiching on the ignition the Fuel gauge moved to about 1/3 full which appeared to be a more accurate indication of the actual fuel. However I read that the fuel gauge should move to full when shorting out the voltage regulator? This didnt happen.
*We added a bit more petrol to the tank and the gauge did move in the right direction. However it appears to be showing 50% of the actual fuel.
*We have ordered and received a new regulator which we plan to fit at the weekend.
We are not sure what to try next if the new regulator or changing the orientation of the sender doesnt fix the problem. Any advice on this would be warmly received. I maybe should have waited to try the above before posting but I thought I'd throw this out there in the interim.
No doubt we will have lots of other questions before we get her back on the road.
Thanks.....
mogbob
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Re: Faulty Fuel Tank Sender / Fuel Gauge

Post by mogbob »

Hi Charlie ,
Welcome to the Forum. Apologies for the fact that your post has slipped by the radar.It's strange times at the moment.

Your post suggests that you have been tracking down the right lines. At this late stage would it be possible to have an update as to whether with new voltage stabiliser and sender fitted you've managed to crack the problem.
With the lower reading on the gauge , is it possible that the sender arm might have been distorted in transit ?
The arm can usually be bent without the use of tools.
I would also advise to not have a " live " connection still operating whilst remove the sender from the tank.
The possibility of an explosion from a stray spark is very real and none of us can react that fast to get away.
I usually remove the sender set up completely , battery disconnect and check it with the Ohms reading on the range of movement empty / full.
Let us know where you've got to and we'll take from there. Good luck with your recommissioning. Sorry you didn't
get a response earlier..... we must try harder.
Bob
CharlieW
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Re: Faulty Fuel Tank Sender / Fuel Gauge

Post by CharlieW »

Hi Bob

Thanks for the welcome and reply. its strange times indeed for us all.
The update is that the new Regulator sorted the issue. The petrol gauge is now giving an accurate reading. We did check the new Sender with the old. The new one, although a diferrent configuartion, had the same dimensions top to bottom. We are hoping the new regulator has also helped the speedo. Last time the car was on the road the speedo was quite erratic. We are not in a position to check this just yet though.
I take your point regarding live connections, stray sparks and open tank. Probably not the smartest move and duly noted. I'll update my dad on this - he was at the business end of the experiment!
We are currently overhauling the brakes and may have to post another query soon.

Thanks again.

C
jagnut66
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Re: Faulty Fuel Tank Sender / Fuel Gauge

Post by jagnut66 »

Last time the car was on the road the speedo was quite erratic
Hi,
This is not uncommon, I've had a few do this myself, it usually means the speedo cable is knackered.
Fortunately it is one of the simplest jobs on the Minor to change it and they are not expensive, so I usually keep a spare.
I've attached a link below for you.
Best wishes,
Mike.


https://www.morrisminorspares.com/body- ... do-p828605
1954 Series 2: 4 door: "Sally" -- Back on the ground with (slave) wheels and waiting to be resprayed......
1970 Triumph Herald 1200: "Hetty" -- Driven back from Llangollen in Wales (twice.....)
CharlieW
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Re: Faulty Fuel Tank Sender / Fuel Gauge

Post by CharlieW »

Thanks for the reply and Link Mike.
Thats really helpful and will I bear in mind if its still erratic. I like the inexpensive and easy fixes.
Cheers again

Charlie
mogbob
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Re: Faulty Fuel Tank Sender / Fuel Gauge

Post by mogbob »

Charlie ,
Glad you were able to crack the problem. One to tick off the big long list ! There's always something to do
on any classic car. Personal safety should always be top of your list with any job , especially if working alone.
We'll sign you up to Michael Caine's " Self Preservation Society " for free.
Keep the questions coming , the vast combined knowledge of the Forum usually comes up with a workable solution.
Bob
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