Preheating a Diesel engine

[boyweevil]

Hi,

This is probably a dumb question but I have never had a diesel. How should I use the engine preheating - manually every time? Is it automatic? What temperature should it be done at? What are the consequences of not doing it?

Thanks

[Nikola]

If you talk about the glow plugs - follow the indicator on the dashboard, it's all automatic. You just wait for it to turn off and you're good to crank the engine.

[deeps]

A modern common rail direct injection engine only requires pre heating when the ambient temperatures are well below freezing. There is a light on the instrument cluster which indicates when the engine is heating and it goes off when it is ready to start, it will only be on for a second or so at normal UK temperatures and you can start the engine as a petrol engine. As the ambient temperature drops the light will stay on longer (only a few seconds) and you start the engine when the light goes off. As Nikola says it is an automatic system.

[boyweevil]

Thanks for your replies .. Will the engine start without preheating it even if its needed?

[aymeric]

Originally Posted by boyweevil

Hi,

This is probably a dumb question but I have never had a diesel. How should I use the engine preheating - manually every time? Is it automatic? What temperature should it be done at? What are the consequences of not doing it?

Thanks

Hi boyweevil.the manual suggests u crank it within 2 seconds of the light going off.it will nearly always start cold(depending on how well its servised)and
if the engine is already hot,i just start it straight away.as regards to starting it right away on a cold morning,think the worst that can happen is a failed start,black cloud of smoke and a drain on the battery

[deeps]

It depends how cold it is. The UK is not usually cold enough to cause starting problems. It has to be about -10C or below before I bother with pre heating, and my car starts instantly. Have a look on Youtube for "Cold start diesel", there are some extreme weather condition starts shown, most not relevant to modern diesel cars. :-)

[derek c]

The modern DI diesel engine does require pre-heating in against a standard DI diesel engine
They have lowered the compression ratio on the modern engine in a car so not to be noisey and use the turbo to get the air in, against high compression ratio truck engine to create heat, hence the introduction of a glow plug for each cylinder and not in the induction manifold
Another way of doing it is to temporary block of the exhaust pipe to get back pressure to create heat

So a pre-heat operation is important, to get a quick start and not to labour everything