Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Fuel tank sender unit/gauge issue.

I drained and flushed my 4/4 fuel tank yesterday to get rid of as much "bits" in the fuel - I have had a couple of incidents with power loss. I put the clean and filtered petrol back in and the fuel gauge hardly moved from empty - there was 3.25 gallons in there. Before flushing the gauge was reading a bit higher. For some reason it is now reading a fair bit lower. I have taken the sender out and the float seems free inside the tube. I cleaned and re-made the wire connections but no change
I have done about 50 miles since and the gauge has dropped very slightly. I estimate just about 2 gals left inside now.
I am doing a long run tomorrow - 200 or so miles so will fill up first and see what the gauge shows.
I read about adjusting the gauge/sender on Gomog so will see what happens with a full tank
Full = 55 litres from spec and calculation from tank dimensios so we will see what happens. Until its sorted I am driving on the odometer!
Anyone had similar-ish problems?

Just finished the checks
I filled the tank and gauge went back up ok.
I did some calculations -
Petrol added = 41 litrs
I estimated that there was about 10 l in the tank to start
Giving tank capacity of 51 l.
Calculated = 55l
A big plus is that I now know a when the tank IS low!
It was sitting bang on empty but had about 10 l in it.
A nice safety margin.

Mine never reads full (1997 +4). Max 3/4.
My 4/4 I had previously did that also and everyone I know has the same quirk.
I use the oddometer & refuel at 200 m.
I get around 29 mpg overall as I do only short runs these days for 55 l would be around 360 m.

John, my '98 +4 gauge never got much above 3/4 when the tank was full either...

On my 4/4 the gauge does almost read full and there are still 8 litres or so left when down near the 'E' mark. After last week's trek, when the tank eventually needs replacing, I will try to fit a larger tank (it's only 9 gallon at present).

Cheers,

10 liter/100km
to calculate when fill up next time

a biger tank , please give info

My gauge also fails to get to the marked "full" too.
However, the exercise did give me a clearer safety margin when low on fuel. Having seen the gauge with my estimate of 10 litres left it gives a better safety target.
I was initially thinking of removing and flushing the tank over next winter. If the troubles return I will remove and possibly look at a new higher capacity tank, but not certain yet.
One definite move is to instal an extra in-line filter between tank and pump - added filtering before any "working bits " .

Just found my handbook for the 4/4 after "losing" it amongst paperwork.
Tank capacity given as 50l / 11 imp gal
4 seater has only 45 l / 10 imp gal
I am away on hols next week but will try scanning the handbook to put on here for anyone who wants the info.
I think someone was asking in another thread.

Mine (2005 4/4) does go to "full" but drops quickly and when "empty" has about 15 ltrs left. On a hilly drive (i.e. everywhere near where I live in N Yorks!) it is all over the place and I have learnt to ignore it and go on distance instead. Getting about 37-40 mpg.

As the tank is not rectilinear in shape it would not be linear anyway - narrower at top than bottom so will go down very quickly when near full, and lack accuracy when near empty. So I'm content that it shows empty when over 1/4 full. Just as long as I remember when it started looking empty...haven't actually run out yet...

Mine's an earlier car, with a smaller tank.
The +4 had an 11 gallon tank, but my 4/4 tank is smaller. I'm just contemplating fitting a later (style) tank when mine eventually fails...

Cheers,

Just catching up on some older threads.

My '01 4/4 has never read above 3/4 when filled either. Like John I go by the trip computer but am a bit braver and usually do 250-300 miles between fills. Not brave enough to go any further though!