my disco died

**Bush65** · 27th December 2009, 03:10 PM

Direct injection diesels with mechanical injection pumps, like the 300Tdi have very few requirements to start and run.

Apart from a battery and an operational starter motor, the only electrical device needed is the fuel shut off solenoid (legal requirement). The 300Tdi has glow plugs, but because it is a direct injection diesel, they are not needed except for extreme cold conditions (rare in Aus).

The solenoid is near the rear of the fuel injection pump and should be energised when the starter key is in the run position. There is one wire with a spade terminal at the solenoid. You may be able to verify that it is operating by listening for it to operate or checking with an alternator when the key is turned on and off. Not a very common problem, but easy to check and eliminate.

The engine needs air, and fuel which is ignited by engine compression. One of these 3 is the most likely fault.

Fuel problems, or more likely lack of, can be:

Contaminated fuel - water or fungus in fuel. 1st check is to drain the sedimentor on the inside of the RH chassis rail near the rear wheel. There fuel drained from the sedimentor should be clean. There may be a little water and sediment as the sedimentors job is to remove these before the fuel passes to the fuel filter. The sedimentor should be drained at regular service intervals.
Blocked fuel filter - the fuel filter has to remove extremely small particles before the injection pump. It should be replaces at regular service intervals, or if you pick up a load of bad fuel. Generally performance will drop of because the filter can not pass enough fuel when the engine requires a higher fuel rate to produce high power output. Fungus will fully block a filter very quickly.
Blocked fuel lines - fungus or bad sedimentation. It should be obvious when the sedimentor is drained if there is fungus (like gray/black snot) or bad sedimentation.
Leaking fuel lines - the very slightest leak will allow air into the fuel lines and will stop a diesel. Any of the plastic lines between the fuel tank and the fuel injection pump can crack. And the crack can even be small enough that you will not detect fuel leaking out when the vehicle is stopped, but still allow air to be sucked in. Leaking fittings (sometimes not tightened properly) are another source for air to be sucked in - those on the fuel lift pump (left side of engine) sometimes develop a leak. The flexible line between the lift pump and fuel filter can fail because Land Rover made it too short and not flexible enough for how much the engine moves.
Leaking fuel injectors - they leak into the cylinder while the engine is stopped and allow air into the injectors.
Faulty fuel lift pump - can be valves, diaphragm or fittings. If the diaphragm fails fuel can leak into the engine sump and contaminate the oil. Sometimes the lift pump can be faulty and the injection pump is still able to pull fuel through the system from the fuel tank, but not be able to when the vehicle is facing up hill or the level in the tank is low. Sometimes only performance suffers but it can make starting difficult.

If the engine compression is too low, the air in the cylinders will not be compressed enough to reach the temperature needed for ignition.

Usually the compression reduces over a longish period as the engine wears and the engine doesn't start as easily as it should and performance drops off. A normal 300Tdi will start before the crankshaft is rotated a complete turn by the starter motor (assuming good battery and starter motor).

Causes of low compression include, worn rings or valves, damaged pistons or blown head gasket.

Another possible reason for your engine not starting is if the timing of the injection pump is out - timing belt jumped a tooth or 2 (not very common). Of course if the timing belt has broken, the engine wont start, but then you would hear the pistons hitting the valves when the engine was turning over.

**Disco_Dan** · 27th December 2009, 09:44 PM

pretty sure that hes truck got a t/belt not all that long ago. and related gear under there...

**disco_mitch** · 28th December 2009, 11:14 AM

yea timing belt was done about 5k ago, as for the rest of bush's explanations they would all make sense but than theres all the coolant that got forced out of the header tank, it has always seemed very gutless

**dullbird** · 28th December 2009, 11:24 AM

Originally Posted by disco_mitch

yea timing belt was done about 5k ago, as for the rest of bush's explanations they would all make sense but than theres all the coolant that got forced out of the header tank, it has always seemed very gutless

You should read my thread to.....have explinations in there as to why the coolant is forced out

**Bush65** · 28th December 2009, 01:03 PM

Originally Posted by disco_mitch

yea timing belt was done about 5k ago, as for the rest of bush's explanations they would all make sense but than theres all the coolant that got forced out of the header tank, it has always seemed very gutless

You never mentioned coolant coolant forced from the header tank or the timing belt before in any of your posts in this thread. Getting information to try and help is like pulling teeth

Edit: sorry, now Lou pointed it out, it was mentioned in the 1st post.

My lame, excuse is that it was some days ago when I read the 1st post, but I didn't respond then because I had no idea what engine was involved. I had a few sleeps before there was enough information to give help and missed that information among the other posts.

... had a look and temp wasnt up poped the bonnet and coolant was overflowing out the lid ...

When coolant is lost and an engine overheats, it is not uncommon to find the temp gauge is not showing abnormally high temperature. This happens because there is no hot water left around the sensor (because the water has been lost).

But while there was water around the sensor, the driver probably missed the temperature climbing, if the overheating came 1st.

Because of this, and since overheating events are bad news ($$$$) with the 300Tdi, many people fit low water alarms. These are good insurance with the 300Tdi.

The water pump is located very high on a 300Tdi so stops circulating coolant when the water level drops. The head develops soft spots when overheated, and want hold bolt clamping force on the head gaskets. If the head has soft spots, it needs to be re-heat treated or replaced.

The 300tdi radiator is not tolerant of much sediment, which will quickly reduce its cooling capacity - only removal of the tanks and rodding out will clean them.

There could be other reasons for water loss, e.g. blown head gasket (common with 300Tdi that have done a lot of km's) or split expansion tank (common with the black tanks).

Water loss will not prevent the engine from running. If the head gasket is blown, usually only one or 2 cylinders will be affected (low compression). That could make starting slower but it should start on the other cylinders.

If the engine overheated badly because it wasn't shut down in time, there could be much more damage leading to no start.

Lack of power before, is subjective and can be down to lack of experience with the vehicle (many people new to diesels don't understand the narrow rev range and assume (during acceleration) when the governor is cutting fuel to stop the engine from going faster, that the engine lacks power, instead of changing to the next gear to reach a higher speed), or could be due to other issues - but that is for another time.

**dobbo** · 28th December 2009, 01:51 PM

Originally Posted by Bush65

You never mentioned coolant coolant forced from the header tank or the timing belt before in any of your posts in this thread. Getting information to try and help is like pulling teeth

Pulling other peoples teeth is easy. Especially if you don't really like the person.

**dullbird** · 28th December 2009, 03:41 PM

Originally Posted by Bush65

You never mentioned coolant coolant forced from the header tank or the timing belt before in any of your posts in this thread. Getting information to try and help is like pulling teeth

He sort of did this was in his first post

driving up the freeway and lost all power than pulled over and she died
had a look and temp wasnt up poped the bonnet and coolant was overflowing out the lid

**Bush65** · 28th December 2009, 07:14 PM

Originally Posted by dullbird

He sort of did this was in his first post

Thanks for pointing that out Lou. I have edited my last post.

**disco_mitch** · 1st January 2010, 11:50 AM

OH YEA
got her back yesterday, turns out it was not so bad, the fuel solenoid cut off had a short and blew a fuse, and the fuel pump was dead, so he sorted all that out with a brand new pump, than the gearbox was 2.5litres overfull and the kickdown adjustment was out by a country mile so he fixed that up to, than when i asked for the damage bill i nearly fell over i mean i was expecting something around 1700 she said oh it come to 656 for everything i had to ask her to say it again, than i went and picked her up and well.......omg talk about love it was like the first time we met all over i even agreed to take her wheeling on saturday and renew our vowes she takes off like a rocket ship she has never gone like this before the gearbox changes like it should its just a dream to drive dont seem to be using the fuel that it was before im so happy so im out there giving her some new bushes in the rear trailing arms, its interesting without a press

**Discovery300Tdi** · 1st January 2010, 03:30 PM

Originally Posted by disco_mitch

OH YEA
got her back yesterday, turns out it was not so bad, the fuel solenoid cut off had a short and blew a fuse, and the fuel pump was dead, so he sorted all that out with a brand new pump, than the gearbox was 2.5litres overfull and the kickdown adjustment was out by a country mile so he fixed that up to, than when i asked for the damage bill i nearly fell over i mean i was expecting something around 1700 she said oh it come to 656 for everything i had to ask her to say it again, than i went and picked her up and well.......omg talk about love it was like the first time we met all over i even agreed to take her wheeling on saturday and renew our vowes she takes off like a rocket ship she has never gone like this before the gearbox changes like it should its just a dream to drive dont seem to be using the fuel that it was before im so happy so im out there giving her some new bushes in the rear trailing arms, its interesting without a press

There you go matey was not that bad. Bloody good start to the year for yourself!!! good to hear that she's all fixed now mate. take care of her.

cheers simon

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