BlackC55,
I replaced the complete fuel intake pipe that runs from the top of the fuel filter to the intake of the low pressure pump today. I then topped up the fuel filter casing and made sure to screw the top on as tightly as possible. I then turned the engine over and it failed to start. So I sprayed some Cold Start into the air intake and the engine then started almost immediately. I ran the engine for around five minutes, then turned it off. I then immediately tried to start it again, and it started. So I then shut the engine off and left it for around ten minutes while I put my tools away. I then tried to start the engine again, and this time it failed to start.
So now I'm back to square one. The engine once started runs very smoothly, and there's no loss of power in comparison with how it was before the starting problem surfaced. I have taken your advice about a leak off test, and ordered a leak off test kit. When this arrives I'll perform the test as per the Youtube videos you put up the link to. However, as there's no rough running or loss of power from the engine, I therefore wonder if it might be something else other than an injector that's at fault? Furthermore, from one of the Youtube videos you put up the link to it would appear that diesels will still normally start if one, or even two of the injectors are leaking fuel. As my engine won't start unless Cold Start is used, I'm beginning to wonder if there's a problem with the actual fuel.
When the starting problem first happened I called the AA, as I have HomeStart cover. When he arrived, the AA man was convinced I'd put petrol in the tank, but I know I filled it up from the diesel pump at my local Tescos on the morning of that day, and indeed after filling the tank I'd driven over 200 miles from my home in Borehamwood to the South Coast and back with no starting problems during that trip. With the AA man's help and some Easy Start I got the engine started and drove the car to a nearby garage. They replaced the fuel filter, but agreed with me that it had been filled with diesel, not petrol. After that, I told them I couldn't afford the £300 they wanted for replacing the low pressure pump, as they thought it was that causing the problem. So instead I started the car with some Cold Start I'd bought, and drove it home, where it's now sitting on my drive.
Since then I've replaced all four glow plugs, fitted a brand new controller, then removed it and put the original back in place, as there appeared to be nothing wrong with it when I dismantled it. I've also replaced the O ring on the output pipe that runs from the low pressure fuel pump to the high pressure pump. I've also dismantled the low pressure fuel pump to find that it literally looked like brand new inside, and now I've replaced the long intake fuel pipe that goes from the fuel filter to the low pressure pump, complete with new O rings. None of these has made the slightest difference to the problem of it not starting without the use of Cold Start.
You say that it could be an injector leaking, so that's next on the agenda, but as the engine ticks over very smoothly and picks up smoothly, I don't somehow think it is one, or even two injectors underperforming.
One peculiar thing is that after I'd fitted the new glow plugs and controller, the engine started correctly without the use of Cold Start, but the glow plug light came back on as soon as the engine started and stayed on the whole time the engine was running. This continued for most of the day, during which time I used the car several times. Later on that day when it failed to start I sprayed Cold Start into the air intake, and as soon as the engine began to pick up I watched to see if the glow plug light would come back on again. It didn't, so I don't know if this has any bearing on the problem, i.e. while the light was continuously on the engine would start normally, but when the light no longer came on (after flashing on for two seconds before I cranked the engine) the engine wouldn't start?
One thing I have noticed is that every time I open the top of the fuel filter, the chamber is only half full of fuel. I'm not sure how this could be, because at the time the engine is turned off the fuel filter chamber should be full of fuel, and unless it's being sucked back into the tank it should remain full until the next time it's started. I'm seriously considering fitting a non-return valve in the fuel line down by the tank, so that when the engine is turned off, no fuel can flow back down into the tank, but instead must stay in the fuel line and fuel filter chamber and hopefully keep it pretty much topped up ready for the next engine start.
Many thanks for your advice on this, I do appreciate it, and I must admit I'm finding it all very depressing having to work my way through all the possible causes of why the bloody thing doesn't want to start, yet runs perfectly once started.
(( I'm a bit lost don't know what to do and just ordered glow plugs in case its them and also relay. I don't know if its any of that to be honest.
