Talk Morgan Forums Morgan Sports Cars Morgan Plus Four, Supersport & Plus Six (CX & CXV Generation Vehicles) Plus Four petrol tank and MPG

I have had my 22MY Plus Four for a month now and have clocked up just over a thousand miles. It's in at Krazy Horse tomorrow for its first service. I have a couple of questions/issues regarding the petrol tank and MPG.

I was told that the petrol tank has a capacity of 39 litres which is apparently true. However the effective capacity is only 30 litres as the fuel pickup does not access the last 9 litres. Quite frankly this beggars belief. Who designs a pickup that only accesses 75% of the capacity of the tank. And why?

I filled up today 4 miles after the warning light came on, with the trip meter on 221 miles, and was able to put 26.5 litres in meaning the reserve is only 3.5 litres. At an average 40mpg this gives you a maximum of thirty miles to find a filling station.

Do any of you guys have any further knowledge of this issue? Plans to put a full reach pickup in maybe? Can we look forward to this fix under warranty?

With regards to MPG I have rather better news. Overall I am achieving an average of around 40mpg and have been told by a man from MMC that in daily use he is averaging 45mpg. My best figure so far was the 78 miles from Thornthwaite (near Keswick) to Scotch corner which I drove during the so called fuel shortage at the speed limit which is for the most part 50, 60 or 70. I achieved 50mpg which I was very pleased with. Conversely having fun on Lake District roads brought the figure down to 30mpg.

Over my eight years (effectively seven years of real use due to Covid) of Morgan ownership I have done some 48,000 miles. The majority of these have been touring France, Spain and Italy along with the UK, especially Scotland. I wish to continue with this level of usage but am somewhat nervous about such a short range. Probably a safe maximum of perhaps 200 miles at the most. Not much for remoter parts of Spain or indeed circular routes in the west of Scotland.

How are you guys getting on with this?

John

That is impressive John. From talking to pals, the normal pattern with toys whether cars or bikes, is an initial burst of use followed by a gradual tailing off as enthusiasm wanes. My Lotus dropped to 700 miles a year and the bike to just 400! Well done.

I have a pal who has a 160k miles Ferrari 360 but he is so unusual that magazine articles are written about him.

Really surprised how small the Plus Four fuel tank is compared to recent classics which carry in the order of 52-55 litres. I can understand MMC taking advantage of the excellent fuel economy but not at the cost of reducing real life range to such a degree.

To be fair I can get a miles to empty figure of 365 miles on the surprisingly accurate readout on my Roadster with full tank under average driving. 39 litres would give you similar at 45 mpg, but how careful do you have to be to average that?

I reckon c 9 - 10 l is not reachable in Belle's tank. I also get the same 365 miles to go at really full but the reality is the 50 miles to empty light comes on after a rapid fall especially from c100 miles to go. At the 50 mile to go point after c 200- 240 miles I can get in typically 35-37 litres. So at at 30 mpg there is left 18 l or c 4 gallons or 120 miles. So it matches.

The 240 mile range only being on long trip say up the A1 to Morpeth, 200 is more the norm.

i have already made 420 km with 30 litres but i dont know if it is possible to use the last 9 litres . The light of the empty tank goes on to early i think.

I have had my car for 2 months and i have traveled 5500 km.
Consumption dropped after 2000km. I think this is the engine break-in period.
The car is equipped with an automatic gearbox.

The consumption is:
Daily use:44,75 MPG (6,3l/100)
Motorway :40,28MPG (7l/100)
Fast drive with sport plus mode:33.5 MPG (8.3l/100).

The range is the same as the 3.7l, around 260 mi (430 km).
During our trip, I wanted to go up to 310 milles(500 km) but my wife was fiercely opposed to pushing the car.
I think the pump is attached to the bottom of the tank. It is reasonable to keep 5 or 7 liters of guard so as not to de-prime the pump when cornering.

John

Don’t forget fuel pumps are cooled by fuel so maybe the MMC are not being as lax as you think and the pump needs to be sat in a fuel ‘bath’?

Simon (SiFab) will no doubt have experience of these pumps and if anything can or should be done to improve pick up. I suspect it’s a case of MMC whacking in the nearest pump that fits the hole but maybe I am being too cynical 😂.

Cheers
Colin

Colin,
it is the Ford pump with in built filter, point taken about cooling.
I decided a while ago not to tempt fate & see how low I could go to avoid muck in the filter.
I try to fill at 200 miles on the odometer . I have toured Euro in my S1 Roadster & even in rural France that range was enough. But I always aim to fill before arrival at the hotel.

Cheers John (V6)

I was unclear as I was answering (and rushing) to answer my buddy John Marchant 🤣

Yup I do the same as you, or rather used to, and used the odometer as the best gauge.

BR
Colin

I raised this same fuel gauge issue some time ago with MMC through my dealer. Their reply seems to be Morgan speak for 'put up with it'.

Amongst a number of problems with my Plus Four (now mostly sorted but some still ongoing) my comments on the fuel gauge were as follows

My comments " Fuel gauge and low level warning light calibration clearly needs some work. Last weekend the low level light came on when the gauge was reading exactly 50% full. Exactly 11 miles later when I stopped for fuel the gauge read 25%. I could then only get 26.75l of fuel in the tank. Needless to say both gauge and the warning light are currently close to no use and need sorting"

MMC's reply was, and I quote "The total amount of fuel that is USABLE in the tank is 33 litres. The actual gauge reading is 27litres From full to empty. There is 5 litres above the float when the tank reads full. This is why it takes a while for the gauge to start to read. Once it starts to read you have 27 litres left. The low fuel light comes on when there is 6 litres remaining. Once the gauge hits the bottom red the tank will only be able to take 33 litres. There is fuel in the bottom of the tank, but this is not useable".

It certainly wouldn't be acceptable on a normal car but in Morgan's view of the world it clearly is justifiable ...

So it looks like you have
- a 38 litre tank according to the Plus Four handbook.
- of that 38 litres only 33 litres are usable (according to Morrgan's reply to me).
- The sender is then calibrated to illuminate the level warning light when you have 6 litres of the 33 litres left.
- meaning you can only use about 27 litres before the light comes on.

That 27 litres correlates with my experience and I have only ever managed to get 28 litres in afetr teh light had been on for a bit. Currently if I am driving normally I aim for fuel every 250 miles. As Spanner Juggler indicates the odometer is still the best gauge in a Morgan.

On a more positive note fuel consumption is pretty good. Mine is an automatic and normally gives 42/44 mpg in mixed driving going with the traffic flow. Although a couple of weeks ago on the Isle of Man for the Motoring Festival it averaged 26 mpg on one tank in Sport+ mode on the unrestricted roads.