Water Tank ; How much when travelling between stops

oilrag

oilrag

Joined
Jan 23, 2023
Posts
97
Likes collected
230
Location
Lincolnshire, UK/ Torre del mar ES
Funster No
93,559
MH
Autotrail Chieftain
Exp
Since 1983 motorhoming ,got the bug in a T2 in 76.
Hello ,just a straw poll type question
How much water do you carry when driving ?

50% or more
Just a little (to save fuel consumption.)

On a recent (sept) big carp fishing trip to central france i carried around 30 litres driving from caen to the venue ,my unit responded with almost a 5mpg bonus over a full water tank .
 
Sort by date Sort by votes
In order to address the doubts expressed by a few about my mpg uplift
I stripped out all un-neccessary gear for my french fishing trip ,ie awning , plus all its bits and bobs 2 heavy sun loungers,the safari room panels and skirts+ poles,,my fishing gear weighed a quarter of that lot.
I also removed the bike rack off the back ,and have recently changed to a single fogstar 280ah in place of 3 x 110ah lead acid .My Autotrail is a tag axle ,rated at 5000kg and im chipped to 175bhp,weight is never an issue .
The cruise from caen down to laval and on to mire was on roads of great quality,so smooth ,and i expect that the weight i lost ,plus a steady light right foot made my fuel consumption improve to 33mpg over the usual 27/8 i get in uk.
 
Upvote 0
Two on Tour said:
If we are travelling to a site where we know there is water, then it can be as little as enough to make a couple of brews.
If we are touring abroad, then we keep the tank as full as possible in case water is not available when we arrive.
Click to expand...
Same
 
Upvote 0
Always travel with a full tank it's only 160 Lt. Never know where you are going to get water next.

We are in Germany at the moment already stopped on 3 Stellaplatz where the water has been out of order and stopped on a few without services.

Although you have to pay in most places in Germany it's cheap €1 for 100 Lt or 10 cents for 10 Lt so easy to top up the tank.

Subscribers  do not see these advertisements

 
Upvote 0
oilrag said:
Hello ,just a straw poll type question
How much water do you carry when driving ?

50% or more
Just a little (to save fuel consumption.)

On a recent (sept) big carp fishing trip to central france i carried around 30 litres driving from caen to the venue ,my unit responded with almost a 5mpg bonus over a full water tank .
Click to expand...

When we are parked next to a lake carp fishing, often for several weeks, I have both tanks brimmed.

We should compare lake notes on venues… 🎣
 
Upvote 0
Seems funny to me that there are some Funsters who are able to predict such things as 25% tank capacity and measure litres per day, when most vans water gauges are rubbish….also, we’ll quibble over mpg that any extra litres will bring, but then max out on wine and beer for return journeys.

I reckon all we need to do is put more air in the tyres, as it’ll surely make us lighter 😀
 
Upvote 0
simsy56 said:
Full water, and empty waste tanks.

Craig
Click to expand...
I empty all water when travelling and just take a 5 litre bottle of fresh water when travelling, never needed any more until I reached my destination. will be doing the same this week travelling to Brands Hatch.
 
Upvote 0
With whatevers in the tank. Never noticed any difference in mpg when running empty or full.
 
Upvote 0
oilrag said:
Hello ,just a straw poll type question
How much water do you carry when driving ?

50% or more
Just a little (to save fuel consumption.)

On a recent (sept) big carp fishing trip to central france i carried around 30 litres driving from caen to the venue ,my unit responded with almost a 5mpg bonus over a full water tank .
Click to expand...
Even in France (best country for dumping and filling up) we apply the principle of dumping and filling up (full) every day (or second day) in anticipation of the next stop not working out as planned; and it often doesn’t as we all know from experience 😃. If there is a MPG price to pay, it’s counter-balanced by the stress reliever of knowing we’re emptied and filled.

Subscribers  do not see these advertisements

 
Upvote 0
We always travel full (or with whatever is left in the tank after an overnight stop).

oilrag said:
On a recent (sept) big carp fishing trip to central france i carried around 30 litres driving from caen to the venue ,my unit responded with almost a 5mpg bonus over a full water tank .
Click to expand...

Whatever the cause of your improved mpg, it certainly wasn’t down to you carrying circa 100Kg less water.

Stoosal said:
I drive with a full tank. The difference between carrying a small amount and a full tank is probably about 3% of overall weight so negligible. I’ve tried with full and empty water tank and I’ve never got anywhere near 5mpg, in fact, I’ve never noticed any difference.
Click to expand...
No surprises there, a full water tank represents about 2% of the overall weight of the van. Even if there was a direct correlation between weight and fuel consumption (there isn’t) there’s no way that a 2 - 3% weight reduction would yield a 17% improvement in mpg. (5mpg improvement on 30mpg baseline).

scotjimland said:
weight of water and fuel make no discernible difference in MPG..
Click to expand...

Indeed.

Barti Ddu said:
On our van the weight of a tankfull of fresh water is around 1.75% of total vehicle weight. Any detrimental effect on MPG is so negligible as to be immeasurable. Certainly it's not going to be in the region of a 5mpg (approx 15%) improvement by ditching it.
Click to expand...

Agreed.

oilrag said:
The cruise from caen down to laval and on to mire was on roads of great quality,so smooth ,and i expect that the weight i lost ,plus a steady light right foot made my fuel consumption improve to 33mpg over the usual 27/8 i get in uk.
Click to expand...

There you go, there are other factors having a greater influence on your mpg than your ditching 100Kg of water. 👍

Ian
 
Upvote 0
ive never dumped fresh water i just run with what ive got if were wilding i fill at every opportunity
 
Upvote 0
I always drain off the water and travel empty, just carry a 5 litre bottle of water should I need a pee.
 
Upvote 0
Northernraider said:
Can't say I've ever noticed any difference in mpg , I fill the tank when it's near empty and not again till its near empty again . On some vans I've clearly noticed a difference in driving if I've filled water, diesel and gas at the Same time. But I think it depends on the van
Click to expand...
Agree. I usually travel with 50%+ water in the tank except in very cold winter weather, and have never noticed any change in fuel economy and I do MPG checks from top to top of the fuel tank. I’m off grid 80% of the time so I make sure the van is fully resourced before leaving home and rarely have to top water up while travelling.
 
Upvote 0
Having to dump our black "to the ground" from a black tank we ALWAYS take advantage when it's available to do so - never know when the next opportunity will be. Less stress.

Also, outside the UK never let fuel tank get below a quarter

Subscribers  do not see these advertisements

 
Upvote 0
This has come up so many times! One issue that hasn't yet been mentioned (I think) is that filling up on departure is so much less stressful than on arrival. When you are leaving a place you know:

  • where the tap is
  • which of the myriad attachments you carry will fit it
  • how busy the place is

On arrival, all this info has to be assimilated as soon as you pull in. So much more relaxing just to park up!
 
Upvote 0
Start with a full tank, when In france I don’t really worry as you can alway fill up. In the uk always run full as you never know we’re your next fill up will be. If you worry about fuel don’t drive a Motorhome.
 
Upvote 0
6 x 5 litre bottles - kept inside the motorhome.

We kow its always ready for tank or coffee. Can so easily topup the tank from inside.
 
Upvote 0
Much though I like water, there are more important things I'd rather carry with my limited payload.
Whatever extra you decide to carry will require more fuel to do so (simple physics) and wear on the vehicle.
 
Upvote 0
Stoosal said:
I drive with a full tank. The difference between carrying a small amount and a full tank is probably about 3% of overall weight so negligible. I’ve tried with full and empty water tank and I’ve never got anywhere near 5mpg, in fact, I’ve never noticed any difference.
Click to expand...
Agreed! Fuel consumption is more to do with driving technique and conditions IMHO.

Subscribers  do not see these advertisements

 
Upvote 0
GeorgeVI was advised as a lad by his grandfather, "sit whenever you can and relieve yourself at every opportunity". The same principle applies to black, grey and fresh water for motorhomes.
 
Upvote 0
cyberyacht said:
GeorgeVI was advised as a lad by his grandfather, "sit whenever you can and relieve yourself at every opportunity". The same principle applies to black, grey and fresh water for motorhomes.
Click to expand...
A lot as been said about payload in the past, water is heavy and I am near to been over weight so I take that in to account.
 
Upvote 0

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Join us

Log in

Already a member? Log in here.

Latest journal entries

Back
Top