300tdi still having starting issues!

The parking nose downhill was only to test the theory. I already had a "Facet" electric pump in the supply system, changed the fuel cut off solenoid, checked filters in fuel line, replaced some hoses that were slightly suspect, checked glow plugs, it made no difference the engine would not start if left overnight with the nose uphill, (my driveway is a medium uphill) as soon as I started parking the Disco by reversing up the drive I had no problem starting in the morning. After replacing the throttle shaft seal it would first start in any position and has done so for the past 4 years.
(Trax), as for this particular type of leak being the same as any other air leak in the system, I disagree, different leaks give different symptoms, I was a Diesel fitter for 45 years, I have seen most types of starting problems with old tech diesel engines.

Gazbo said:

The parking nose downhill was only to test the theory. I already had a "Facet" electric pump in the supply system, changed the fuel cut off solenoid, checked filters in fuel line, replaced some hoses that were slightly suspect, checked glow plugs, it made no difference the engine would not start if left overnight with the nose uphill, (my driveway is a medium uphill) as soon as I started parking the Disco by reversing up the drive I had no problem starting in the morning. After replacing the throttle shaft seal it would first start in any position and has done so for the past 4 years.
(Trax), as for this particular type of leak being the same as any other air leak in the system, I disagree, different leaks give different symptoms, I was a Diesel fitter for 45 years, I have seen most types of starting problems with old tech diesel engines.

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i meant the parking downhill should also hide the other leaks as if it's steep enough gravity will help prevent the fuel draining back. not agree?

Hey Trax, no, not really because the pump is isolated on the supply side from the system by the shut off solenoid the only way to lose prime in the injection pump feed gallery when the engine is stopped is an air leak in that top chamber of the pump, and if there is no show externally on the IP body or into the timing case then it is a backflow problem that shows no external signs of leakage, only atmospheric pressure is involved, no high pressure.
The fuel return system is always open back to the tank, the fuel siphons via the excess fuel system from the pump gallery.
Air leaks in the system between the tank and the fuel inlet solenoid will show up as an accumulation of air in the filters until this gradually starves the IP of fuel, the engine may keep running but gradually lose power until it may not run above an idle, so this is a distinct problem that would not cause such a starting problem when cold.

Gazbo said:

Hey Trax, no, not really because the pump is isolated on the supply side from the system by the shut off solenoid the only way to lose prime in the injection pump feed gallery when the engine is stopped is an air leak in that top chamber of the pump, and if there is no show externally on the IP body or into the timing case then it is a backflow problem that shows no external signs of leakage, only atmospheric pressure is involved, no high pressure.
The fuel return system is always open back to the tank, the fuel siphons via the excess fuel system from the pump gallery.
Air leaks in the system between the tank and the fuel inlet solenoid will show up as an accumulation of air in the filters until this gradually starves the IP of fuel, the engine may keep running but gradually lose power until it may not run above an idle, so this is a distinct problem that would not cause such a starting problem when cold.

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sounds good

i'll have to have a butchers at the diagrams to fully see it

(Sorry op slight hijack here : ) Gazbo, so my problem of low idle for a minute or so when left overnight looks like an air leak tank side of solenoid? I did the leak off pipes and lift pump etc.. like the op but still a hesitation on starting in morning then low idle for half a mile or so.

ronsealdeath said:

(Sorry op slight hijack here : ) Gazbo, so my problem of low idle for a minute or so when left overnight looks like an air leak tank side of solenoid? I did the leak off pipes and lift pump etc.. like the op but still a hesitation on starting in morning then low idle for half a mile or so.

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You could have one of a few problems or a combination, if you can do so, try the little test by parking nose downhill overnight, (does not need to be a really steep angle, but maybe rear wheels a foot or so higher) with a full tank of fuel.
You could have an air leak somewhere between the tank and lift pump, check the primary filter, the one under the Disco RHS rear first, for any evidence of leakage with a full tank and engine off, check the fuel lines right from the tank along the chassis for leaking where rubber sections join poly lines. Remember that when the engine is running these lines and filter are under suction pressure, so if they are leaking any fuel under atmospheric pressure, even slightly they can and will draw in air when the engine is running. Usually any leaks in the secondary (main) filter will actually show as leaks because this section is under pressure from the lift pump when the engine is in service. The other thing that could cause your problem is partial blockage of either filter, the lift pump may take a while to "make up" the full fuel level to the IP gallery.

Gazbo that's really useful info, thanks very much.

Gazbo said:

I have had this same cold starting problem and it was the throttle shaft seal in top of the Bosch VE injection pump. If this seal is leaking, (sucking air), it allows the fuel in the top, (inlet), chamber of the pump to drain back to the tank via the return fuel line when the engine is not running, thus little or low fuel prime to the injector elements for that first start of the day. The problem is time based, the longer the vehicle stands the more likely it is to be a hard start.
To test, make sure the fuel tank is more than half full and overnight park the Disco nose downhill as steep as possible, if this seal is the problem the engine should start straight up cold no worries after being parked this way, conversely if you park on the level to nose uphill position you will find it will persist with no start straight away after standing overnight.
The pump throttle shaft seal is cheap and easy to replace.

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Sorry to bother you again... you say the pump throttle shaft seal is wasy and cheap to replace? Do you know where I can find out how to go about this? I have searched online, but cant seem to get anywhere

thanks again

Im having the same problem at the minute. Replaced the sender with a new 1.problem went away and week later returned.

Can people please stick us sum pics of the

Throttle seal in the pump
Leak off pipe
Fuel solinoid and how i test that please.

Ive got easy start ready if needed but want to solve problem not cover it up.

SenseiLeon said:

Sorry to bother you again... you say the pump throttle shaft seal is wasy and cheap to replace? Do you know where I can find out how to go about this? I have searched online, but cant seem to get anywhere

thanks again

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I thought that there may be some useful posts regarding this particular job on Landyzone, but maybe not, there is a lot of info on the Bosch VE pump, (some quite detailed), on the Australian Land Rover Owners forum, you could do a search on AULRO, that is where I found the info that pointed to the problem.
My parts, the throttle shaft seal and top chamber rubber seal gasket I purchased from a local Diesel repair shop that carried Bosch IP parts, cost here was $1.00 AU for the shaft seal, (simply an "o" ring) and $5.00 for the top chamber gasket, as to how to do the job, it is simple if you have reasonable mechanical skills, there are a couple of parts of the operation that require particular care to avoid damaging some internal linkages, the whole job took about 30 minutes. But again I recommend you try the "parking nose downhill with full fuel tank test", this will confirm the problem is indeed the throttle shaft seal.

..Just a quick update....
after being advised by a mechanic that it was definately a fuel starvation issue for not starting I replaced all fuel lines, leak off pipes, new lift pump, new fuel shut off solenoid, removed in line filter, replaced fuel filter, fitted a one way valve in engine bay, tested for throttle shaft seal, new battery, I decided to replace the recently changed glow plugs and renew the feed wires to the glowplug relay, this morning she fired up first time!, no easy start, no turning over, immediate start...

So, for all those who say 300tdi engines do not need glowplugs, mine certainly has done . And this is after a mild winter, anyway, I like her again now, and can treat her to all the other jobs that needs doing, but have been too p@@sed off with her to do!!

SenseiLeon said:

..Just a quick update....
after being advised by a mechanic that it was definately a fuel starvation issue for not starting I replaced all fuel lines, leak off pipes, new lift pump, new fuel shut off solenoid, removed in line filter, replaced fuel filter, fitted a one way valve in engine bay, tested for throttle shaft seal, new battery, I decided to replace the recently changed glow plugs and renew the feed wires to the glowplug relay, this morning she fired up first time!, no easy start, no turning over, immediate start...

So, for all those who say 300tdi engines do not need glowplugs, mine certainly has done . And this is after a mild winter, anyway, I like her again now, and can treat her to all the other jobs that needs doing, but have been too p@@sed off with her to do!!

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you did it all at the same time? if so, then how do you know it was the glowplugs?

also, *good* 300tdis don't need glows unless it's cold

trax said:

you did it all at the same time? if so, then how do you know it was the glowplugs?

also, *good* 300tdis don't need glows unless it's cold

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Lol, no did it all over a few months, and put up with easy start when I needed to fire her up..

As for 'good', I don't know, but I don't feel mine is too bad, she has done 220,000 now, but never misses a beat(once started...!) and still has good power. Okay, the boot floor is rusted through, and the sunroofs still leak a bit, and I just replaced the alternator, and front prop.... and so it goes on....
:violin:

Certainly the 300TDIs with edc need good glow plugs, and a sound battery to give a good cranking speed for reliable starting.

Have you tried starter.mine had the same issue. And i thought fuel side replaced all the fuel side and new battery and it turned out to be starter which was 6 months old was lazy. Worth a try mate

SenseiLeon said:

Lol, no did it all over a few months, and put up with easy start when I needed to fire her up..

As for 'good', I don't know, but I don't feel mine is too bad, she has done 220,000 now, but never misses a beat(once started...!) and still has good power. Okay, the boot floor is rusted through, and the sunroofs still leak a bit, and I just replaced the alternator, and front prop.... and so it goes on....
:violin:

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it's working for you now, so meh

but it does sound a like something's still iffy. upto you if you want to keep checking or leave it a while and see if something presents itself.

My 300tdi also had a similar issue needing the glow plugs to start every morning, turned out that the valve clearances needed adjusting