Running Out Of Diesel

[tubaman]

Having never owned a diesel before, I am being told that if you run out of diesel its a major problem that will cost alot of money.

Can anyone confirm if this is indeed correct these days on a modern diesel ?

[Daveyonthemove]

Its not really the case these days.

Old cars used to have to be bled in order to get the air out of the system, but these days you can refill and use a hand pump to bulid the pressure back in the fuel lines. It will probably stutter a bit to begin with, but it should drive fine once you have got going.

I think the biggest (possible) issue could be the fuel pump in the tank overheating and starting to break up. Its not a common problem, but the lower the fuel in the tank, the higher the risk.

With Toyota's low fuel warning, you should still manage aprox 80 miles before its dry, and that should be sufficient fuel to keep the pump submerged and avoid issues.

[acetip]

Its not really the case these days.

Old cars used to have to be bled in order to get the air out of the system, but these days you can refill and use a hand pump to bulid the pressure back in the fuel lines. It will probably stutter a bit to begin with, but it should drive fine once you have got going.

I think the biggest (possible) issue could be the fuel pump in the tank overheating and starting to break up. Its not a common problem, but the lower the fuel in the tank, the higher the risk.

With Toyota's low fuel warning, you should still manage aprox 80 miles before its dry, and that should be sufficient fuel to keep the pump submerged and avoid issues.

VW had self bleeding/priming systems 25 years ago im surprised toyota do not.but there swings and roundabouts.

[Daveyonthemove]

Toyota might have this system, i don't know to be honest.

Its not something i've had to worry about really

[Lupidog]

Diesel fuel injection pumps are fuel lubricated. You risk damaging the pump if you run dry. It's an expensive piece of kit.

[Jamesbelfast]

Modern high pressure diesel engines are all self-bleeding - that's the principle of how the high pressure fuel pump works.

I have yet to find a diesel vehicle with a primary fuel pump in the fuel tank. If it is necessary to have one it will be an in-line unit coupled to the electrical fuel control systems.

If the vehicle has a hand operated primer pump then there definitely will be no need for an electrical primary pump.

The golden rule is this.

If it has a hand-primer (usually a rubber bulb or large primer button on the fuel filter) the procedure is to add fuel to the tank - prime the system until the bulb or buttom until it goes firm. Then crank the engine over in 5 second bursts until it kicks into life. If you can get another person to keep priming the bulb during cranking all the better

Om cars with electrcial primary pumops (sometimes referred to as scavange pumps) just switch the ignition off and on 3- 4 times then commence cranking the engine in 5 second burts until it fires up.

Once the engine seems to be catching keep you foot on a very light throttle and allow the engine to run - this allows any trapped air to escape.

For obvious safety reasons in-tank fuel pumps fitted to modern petrol cars have to be fail-safe should the tank become empty so the days of these pumps disintegarting are long gone. The last time I heard of such an incident was around 1985 (25 years ago) on a Ford Escort.:)

[Lupidog]

Just incase you misunderstood my post. I meant the fuel injection pump and not the fuel supply pump. The tolerances inside the injection pump are too fine to be lubricated by engine oil, so the fuel passing through the pump is used. If the pump, which is mechanically driven from the engine runs dry of fuel, it loses its lubrication and can fail destructively. I agree more so on older vehicles simply because as James so rightly said, most modern vehicles have self bleeding systems. Unfortunately this is only of advantage to the injection pump when restarting the engine after topping up with fuel. On older vehicles injection pumps failed more often by people turning their engine over in the vain attempt to restart it without venting the fuel system, thus turning the fuel injection pump dry. If I misunderstood your reply then ignore this post :)