?? a Fuel tank problem ??

[c11babe]

My camper use to be 1.9 petrol injection however converted to carb after many many years of unreliability problems. Just prior to the conversion the fuel tank was replaced as it had been thought the old fuel tank was corroded and may have been causing a few problems, I was told the fuel tank for an injection ran camper was different to that fitted to a carb running camper.

Since having the carb converstion completed I have always noticed that when the camper is left for a few days it takes a while to start - as if its waiting for the fuel (engine turns over almost flattening the battery) before it starts, also the camper always needs quite a bit of revs and can feel quite flat when starting from junctions etc. I know when the conversion was done the camper was changed to mechanical fuel pump.

I have no idea but could the above be related to the difference between the fuel tank??

Many thanks

[CovKid]

Firstly, you'll need to ascertain whether fuel is or isn't getting to the carb within a sufficient amount of time. If it starts pretty much straight away after a small capful is poured down the carb throat, then fuel starvation is likely. You could switch to an electric pump which would help prime the line prior to starting. You don't say whether it was a new fuel pump or one that may have seen better days.

[c11babe]

The fuel pump was changed from electric fuel pump to mechanical fuel pump when converted from the injection to carb, thanks for your help

[Mocki]

One of your problems maybe the injection tanks have a bigger bore outlet than the carb versions..... However I have been running a carb on a injec ton tank for years with no noticeable issues.... I would recommend changing to a elec tric fuel pump tho, much better as it primes before you crank the engine over, as Ralph said above and much cheaper than a mechanical pump to replace too

[kevtherev]

which pump would you fit Steve?

[Mocki]

Kev i have fitted one the same as this, from this seller, it fits nicely on the inner chassis rail, next to and before the inline filter, and switches with a 30amp auto relay in place of the fuel cut off solenoid from the lpg system and increased my mpg by not needing the push rod or mechanical pump!

http://www.ebay.co.uk/itm/12V-ELECTRIC- ... 3cc86f3d7a" onclick="window.open(this.href);return false;

[Plasticman]

do you know what it flows when not on load , Im looking for one for fuel transfer only
mm

[Mocki]

MM follow the link and then look at sellers other items, he has what you are looking for i think......
i cant answer your question, dont have the paperwork anymore....

[edoh]

Thanks for the link -
Can you remember which model worked for you?
the basic £15:99 or the beeeg pricey £100+ jobbies?
Thinking of getting an electric pump - with limited budget

[California Dreamin]

I just find it strange that the fault would be related to the fuel pump given that it now has a carburettor that presumably has a float chamber full of fuel.
The 'priming' on fuel injection models is there because the fuel system is pressurised and relies on that residual pressure for quick starting...not so on a carburettor model!
More likely an issue with the choke mechanism.

Martin

[Mocki]

I just used the basic pulse pump, as in the first link... It's good for up to 3l carb engines, and it stops all that fannying about with push rods and mechanical pumps ... Bear in mind i only used about £20 of petrol in ten years, it can take a awful long while for a mechanical pump to prime it's self up....

Frankly for about £25 all in with the relay and wiring it is a much cheaper than a replacement mechanical pump anyway.....

[California Dreamin]

I just used the basic pulse pump, as in the first link... It's good for up to 3l carb engines, and it stops all that fannying about with push rods and mechanical pumps ... Near in mind I on
Unused about £20 of petrol in ten years, it can take a awful long while for a mechanical pump to prime it's self up....
.....

Point is Steve...starting a carb engine from cold doesn't require any 'petrol pump priming' thepetrol should already be sat there in the carburettor's float chamber. However, injection systems are different because they are 'pressurised' and often these types of systems use an accumulator (diaphragm and spring) to hold that pressure for the injectors.
I shall have to take a close look at the Digifant and Digijet tech data for exact operation.

Martin

[edoh]

thanks for the info -
and varied views -
will help us make a good decision

[kevtherev]

I just used the basic pulse pump, as in the first link... It's good for up to 3l carb engines, and it stops all that fannying about with push rods and mechanical pumps ... Near in mind I on
Unused about £20 of petrol in ten years, it can take a awful long while for a mechanical pump to prime it's self up....
.....

Point is Steve...starting a carb engine from cold doesn't require any 'petrol pump priming' thepetrol should already be sat there in the carburettor's float chamber. However, injection systems are different because they are 'pressurised' and often these types of systems use an accumulator (diaphragm and spring) to hold that pressure for the injectors.
I shall have to take a close look at the Digifant and Digijet tech data for exact operation.

Martin

Actually on LPG the lag while the float bowl fills while switching to petrol is long on mech pumps
Also if the bowl is not full due to poor fuel delivery the starting would be disadvantaged

[Mocki]

Martin, let me reassure you, that if the bowl is empty or low it will not start until it has fuel...which with a poor mechanical pump can be never.... Even switching over at 60mph it might not be primed be fore standstill if the pump is knack erred..