Thread: Why does tdi stop when key turned off?

Most modern diesels have a fuel shut-off solenoid or injector shut-off. Gone are the days where you had to pull the shut-off (or STOP) cable. (except for the Britts - where anything could be possible - maybe an Ethiopian sitting under the bonnet with a light in front of him when the key is turned off the light goes out and he turns off the fuel. He survives by eating bugs and the occasional cat that wanders in, but it is better than living in Dafor )

If I were you I'd make sure it doesn't start by pulling the wire off the shutoff solenoid which you can find down under the injection pump, a bit towards the righthand (from the drivers seat that is) fender but in front of the coolant expansion tank. Seek and ye shall find.
A.

It is essential from a safety point-of-view to disconnect the lead from the solenoid shut-off before rotating an engine which can be started.

Why pull it forward in top gear?...... it can be readily rotated by hand by ring spanner or socket on the crankshaft harmonic balancer (pulley) retaining nut (27mm), working from under the vehicle. That way a manual can be in neutral and the handbrake applied.

reagrds - Laurie

it stops in exactly the same way that you do with the pull to stop systems. you turn the fuel off before it gets to the combustion chamber. In a pull to stop system what your doing is pulling on a lever thats shifting the fuel rack/collar/sleeve to the no fuel position. Some electric systems just use a solenoid (or a cable pull motor like the suzis use) to achieve the same result by pulling on the same lever, others use the solenoid to directly push the rack to the stop position and others use the solenoid to open or close a port (depends on configuration) that stops the injector pumps from pumping or recieving fuel.

Modern diesels with electronically managed injection just stop telling the injectors to inject.

A fair question I thought.

as for it starting off of the crank by turing by hand... I doubt it.. It would have to be hot, and youd still have to be cranking... theres about 30 minutes worth of prep work to try and crank start a series diesel and even then you have to rely on having enough juice to get a couple of glow plugs going.

to make life easier for turning it over remove the glow plugs which ensures it cant start as it has no compression and allows you to eyeball the condition of them and if you know how to read a glow plug the health of the engine (its the equivelent of reading the plugs on an engine)

Originally Posted by boggo

Love the stamp i think i need one at work.