necking the tank?

[Lazy-Ferret]

I wondered if anyone else has experienced this?

When I used to use only diesel, I always filled the car till the pump stops, and then round up to the next pound. Sometimes, I would miss, and could just get the next pound in, but sometimes, I would fill up to the neck, before I got to the next round number, and just have to stop.

Since using the Veg Oil, I often put 40 litres of diesel in, and then drive home, to add 30litres of veg oil, but if I get it wrong, I end up with the tank full to the top, and a little bit left over... this means I have been necking the tank a lot more often.

Now, the question is, I think I have discovered that when the tank is full to the very top, the car is lumpy when cruising. If I am sitting at a steady 30, it feels like it pulls back a bit every so often, take her up to 70, and she climbs just fine, but once I then level off at 70, she starts the hesitating, stuff my foot dawn, and she is fine again. After about 30 miles, when the fuel needle has just started to drop, she is back to running normally... Any idea why? Could it be related to the full tank?

 

[solarman216]

my guess is that without enough air space in the tank the hydraulic governor, is being affected by back pressure, Rick

 

[Lazy-Ferret]

my guess is that without enough air space in the tank the hydraulic governor, is being affected by back pressure, Rick

so to ask a silly question, what is the Hydraulic governor, and what does it do, when it is not getting upset that I have over filled the tank...

 

[davenclaire]

proberly blocking the tank breather pipe and air locking the fuel system. but why are you carrying around so much extra weight i mean all the fuel weighs loads so not good for overall economy

 

[Sweety]

proberly blocking the tank breather pipe and air locking the fuel system. but why are you carrying around so much extra weight i mean all the fuel weighs loads so not good for overall economy

That was my first thought about it air locking. TBH I like to have a full tank just incase we have to jump in the truck & dash across country due to my Mother taking ill again or the 400+ mile trip down to South Wales if my Father inlaw was to take ill again

 

[Lazy-Ferret]

proberly blocking the tank breather pipe and air locking the fuel system. but why are you carrying around so much extra weight i mean all the fuel weighs loads so not good for overall economy

I used to drive for a living, often doing 800 miles or more in a day, so got into the habit of filling up as I would have to do it 2 or 3 times a day. I think it is because of this, I really hate putting fuel in the car, and the time it wastes doing it and then queueing to pay for it, so this way, I only have to do it every couple of weeks now, and never have to worry if I have enough fuel for an emergency trip out.

 

[geoffdown]

the breather I believe is a flap valve in the filler cap but when using veg up to the cap it helps to stick the valve more than when on diesel as the fuel is being used it can still coat the cap with veg when u go round corners so might be ur problem just a thought:thumbs

 

[Lazy-Ferret]

the breather I believe is a flap valve in the filler cap but when using veg up to the cap it helps to stick the valve more than when on diesel as the fuel is being used it can still coat the cap with veg when u go round corners so might be ur problem just a thought:thumbs

I will look at that, as I have noticed that since using the veg oil, the hinged flap/cover over the filler cap gets a sticky coating on it, that I have to wash off, which I did not get with plain diesel.

I might try and flush the cap with a bit of petrol, to clean it out.

I hope that as I get the hang of this, not to fill it up so much, which should cure the problem anyway, as it only does it for the first 30 miles, then it is business as usual, I only posted to see if anyone else had noticed it.

 

[solarman216]

so to ask a silly question, what is the Hydraulic governor, and what does it do, when it is not getting upset that I have over filled the tank...

this is the item that controls the fuel, re fuel to the engine relative to revs and throttle position etc, it relies on a free back path to the tank to establish a norm, over filled tank will have a back pressure on this governor so upsetting its norm, Rick

 

[Lazy-Ferret]

this is the item that controls the fuel, re fuel to the engine relative to revs and throttle position etc, it relies on a free back path to the tank to establish a norm, over filled tank will have a back pressure on this governor so upsetting its norm, Rick

Ahhhh... cheers Rick.. makes sense now...