VW LT35
I wish to add a small fuel tank to this madel (deisel).

The existing tank has a flow and return line, so that excess pumped fuel 
is returned to the tank.

Can someone advise what proportion of pumped fuel is returned?

I wish to add a 7 litre tank - but for simplicity to connect only a flow 
pipe - excedss fuel being returned to the existing tank.

I need to consider the situation when the main tank is full - if a small 
amount of fuel is returned, this will not be a problem considering the 
size of the additional tank.

Also, can anyone advise on taps/shutoff valave for use on a fuel line, 
so that I may select which one is "open"?

Thaks

Eric

Eric wrote:
> VW LT35
> I wish to add a small fuel tank to this madel (deisel).
>
> The existing tank has a flow and return line, so that excess pumped
> fuel is returned to the tank.
>
> Can someone advise what proportion of pumped fuel is returned?
>
> I wish to add a 7 litre tank - but for simplicity to connect only a
> flow pipe - excedss fuel being returned to the existing tank.
>
> I need to consider the situation when the main tank is full - if a
> small amount of fuel is returned, this will not be a problem
> considering the size of the additional tank.
>
> Also, can anyone advise on taps/shutoff valave for use on a fuel line,
> so that I may select which one is "open"?
>
> Thaks
>
> Eric

It won't work, the extra tank will rapidly empty itself to the big tank via 
the return (which is very quick).  If you want an extra tank as a reserve 
then it really is easiest to just carry a can.  If you wnat one to run a 
heater, then again just have an extra can or tank.  If you want to increase 
overall capacity then add a linked tank, but bear in mind you can then have 
problems if you park on a hill with low fuel and the extra tank lower than 
the main tank.  If you are determined to do it then you need to add t pieces 
into the system and have a tap on every line (my land rover had three tanks, 
all with flow/return and a heap of taps.)

"Eric"  wrote in message 
news:4884460b$0$658$bed64819@pubnews.gradwell.net...
> VW LT35
> I wish to add a small fuel tank to this madel (deisel).
>
> The existing tank has a flow and return line, so that excess pumped fuel 
> is returned to the tank.
>
> Can someone advise what proportion of pumped fuel is returned?
Very variable depending on engine speed and throttle setting, eg downhill 
coasting a lot is returned, uphill with hard throttle a lot less

> I wish to add a 7 litre tank - but for simplicity to connect only a flow 
> pipe - excedss fuel being returned to the existing tank.
Not a good idea


>
> Also, can anyone advise on taps/shutoff valave for use on a fuel line, so 
> that I may select which one is "open"?
>
Landrovers, particularly older ones have a twin tank system with a change 
over valve, you might find one from a scrap yard, dealer?


-- 
Chris, (on tour)
Intellect is invisible to the man who has none.
Schopenhauer

Cerumen wrote:

> Landrovers, particularly older ones have a twin tank system with a change 
> over valve, you might find one from a scrap yard, dealer?

I've certainly come across ex-MOD petrol ones, not sure I've seen any 
diesel ones with twin tanks though.

"Eric"  wrote in message 
news:4884460b$0$658$bed64819@pubnews.gradwell.net...
> VW LT35
> I wish to add a small fuel tank to this madel (deisel).
>
> The existing tank has a flow and return line, so that excess pumped fuel 
> is returned to the tank.
>
> Can someone advise what proportion of pumped fuel is returned?
>
> I wish to add a 7 litre tank - but for simplicity to connect only a flow 
> pipe - excedss fuel being returned to the existing tank.
>
> I need to consider the situation when the main tank is full - if a small 
> amount of fuel is returned, this will not be a problem considering the 
> size of the additional tank.
>
> Also, can anyone advise on taps/shutoff valave for use on a fuel line, so 
> that I may select which one is "open"?

Search google for svg or vegetable oil or bio-diesel conversions.  Although 
you're not doing this there's loads of advice regarding second tanks and 
changeover valves which is what you need.

Rgds

Andy R

"Willy Eckerslyke"  wrote in message 
news:6ej9jdF7a4i1U1@mid.individual.net...
> Cerumen wrote:
>
>> Landrovers, particularly older ones have a twin tank system with a change 
>> over valve, you might find one from a scrap yard, dealer?
>
> I've certainly come across ex-MOD petrol ones, not sure I've seen any 
> diesel ones with twin tanks though.

I had one that had been converted but so long ago I can't remember the 
details of the plumbing.

-- 
Chris, (on tour)
Intellect is invisible to the man who has none.
Schopenhauer

"Eric"  wrote in message 
news:4884460b$0$658$bed64819@pubnews.gradwell.net...
> VW LT35
> I wish to add a small fuel tank to this madel (deisel).
>
> The existing tank has a flow and return line, so that excess pumped fuel 
> is returned to the tank.
>
> Can someone advise what proportion of pumped fuel is returned?
>
> I wish to add a 7 litre tank - but for simplicity to connect only a flow 
> pipe - excedss fuel being returned to the existing tank.
>
> I need to consider the situation when the main tank is full - if a small 
> amount of fuel is returned, this will not be a problem considering the 
> size of the additional tank.
>
> Also, can anyone advise on taps/shutoff valave for use on a fuel line, so 
> that I may select which one is "open"?

Can;t think why you want to add just 7 litres,

on my iveco motorhome i added a second diesel tank, giving me 140 litres 
fuel capacity, and a couple of change over fuel solenoids sort out switching 
between the tanks, but it was very easy to add the second tank to my icveco, 
i used another iveco tank mounted next to the origional one, as this vehicle 
used truck stle chassis rail mounted tanks.

The LT has a squat tank slung between the chassis rails at the back, you can 
get a long range fuel tank for the LT, it's just deeper than the stock one, 
not sure of the capacity, but it'd cost well over a hundered quid to fill 
it.. mind the normal LT's 70 litre tank dosent cost far off that to fill 
nowadays.

As others have said, theres a hell of a lot of flow on the return when the 
engine isnt running fast, i ran some fuel injector cleaner through my lt's 
engine years ago, it was the type you disconnect the fuel lines and run the 
engine off this stuff, destructions said to plonk both feed and return lines 
into the bottle, but i thought i was being clever by just using the feed 
line, took about 2 minutes to empty the half a litre of cleaner, about 90% 
of it had been dumped into the fuel tank via the return line.

So to plumb in a second fuel tank you'll need a couple of diesel resistant 3 
way valves, manual ones prolly cost a tenner each,
i used solenoid valves for my iveco tank change over, there's a bloke on 
ebay who sells them, (search for 3 way fuel change over solenoid) cost me 
about 30 quid each when i got mine, need 2 of them of course.. one for flow 
other for return, but that's a bit overkill just to plumb in a 7 litre tank, 
i used to carry a 10 litre plastic diesel can with my in my LT, made up a 
bracket to hold it underneath the van next to the main tank, not taking up 
room inside the van, and easy enough to get to if needed.

"Eric"  wrote in message 
news:4884460b$0$658$bed64819@pubnews.gradwell.net...
> Also, can anyone advise on taps/shutoff valave for use on a fuel line, so 
> that I may select which one is "open"?


http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=200213078521