Engine Start/Fuel Pump Problems on Td5

[StephenH]

Adding to my Land Rover woes of the past month (which is a topic for another time!), I have been having some real issues with starting my 2005 Defender Td5 in the past couple of weeks. It got so bad that I didn’t want to risk the ferry or any trips away from base.

Symptoms:
- whining fuel pump in the tank
- having to crank for a long time before engine fires up
- fuel pump would time out before attaining pressure
- sometimes no start at all

If you do need to get the fuel pump out, you can either drop the fuel tank or cut a hole in the floor above the pump and get at it that way. I had reached the point where I thought that changing the pump might be the solution and had gone as far as to mark the cut point in the floor and had got the saw out. This way I could get the pump out myself without having to drain the tank, remove the anti-roll bar, the long range tank and the trailer hitch braces.

However… there seems to be numerous issues that can affect the fuel pump that aren’t actually anything to do with the fuel pump itself and since access to the fuel pump is difficult, its best to exhaust other possibilities first. So I changed the fuel filter and the air filter, checked the ignition loom, checked for leaks at the fuel pressure regulator and run the fuel/air purge process several times - all to no avail.

Then late in the night while I was contemplating options, I came across a possible solution I hadn’t tried, and its so simple I just had to try it first. It is an issue with the Air Bleed Valve Fuel Filter (WJN500110-BP for Defender 2000-2006, Discovery 2). Apparently, if the air bleed valve gets blocked it can lead to the symptoms I had. So here’s what I did:

Remove the guard cover from the fuel filter for ease of access and locate the Air Bleed Valve Fuel Filter. This is the first fitting coming out of the Fuel Filter housing in the right rear wheel well.

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Pull back the rubber cover and remove the pipe connection by squeezing the fitting and easing it away from the brass pipe. Using a 19mm deep socket or wrench, remove the brass fitting from the fuel filter housing. There is a copper washer - don’t lose this unless you have a spare on hand!

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Once the brass fitting is removed you will see a small plastic insert in the brass fitting.

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Gently ease the plastic fitting out. You can try to blow through this fitting to see if any air can pass through. Mine was completely blocked.

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You will need to separate the three holed plastic button-type end from the rest of the fitting by easing around the edges with a sharp blade. This will reveal the paper filter. Scrape the gunk off the top of the filter and check for air flow by blowing through the fitting.

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Once cleaned, snap the button back on the end and re-instal the plastic filter assembly back into brass fitting and re-instal the whole thing back onto the fuel filter housing.

I did not run the fuel purge sequence, but the truck started after about 4 seconds of cranking. On all subsequent tries at starting the engine fired up right away and the whining from the fuel pump has gone away completely. I will order a new Air Bleed Valve Fuel Filter and replace it anyway, but at least now I can drive the truck again, and, as I had hoped, it wasn’t the in-tank fuel pump at all.

If you are having starting problems, I hope this will help.

[Rob]

Land Rover: Making Mechanics out of Owners since 1948!

Great article and awesome troubleshooting, thanks for sharing your solution.

[ANDYD]

Agreed, good to see a good news solution post, nice description and photos.
Glad you have it sorted, we missed you on the last couple of club trips!

I don't think I have one of them on my Defender but I will be checking (just in case) on the weekend.

Cheers
Andy

[StephenH]

Ya, its amazing that such a tiny piece could cause so much trouble. Part of the problem was the inconsistency of it. Sometimes it would start after a few cranks and other times not at all. Sometimes you could get it going and drive somewhere and it when you started up the second time it would fire quite easily, other times you’d be cranking and nothing would happen.

But it did seem to be a fuel starvation type issue and the fact the fuel pump was whining and wouldn’t attain proper pressure made me think it was a failing fuel pump or maybe just clogged with diesel snot or the likes.

Apparently the crank position sensor is sometimes the culprit, sometimes something as simple as a weaker battery not getting the starter motor going fast enough. My battery is fine but I tried charging it and then starting with the charger in plugged in to supply mode just to ensure that any voltage drop due to cranking didn’t slow it down. But I also didn’t want to kill the starter, so was conscious of the 20 second crank limit and appropriate cooling time. Sometimes if it did fire up, it would really struggle to life and you’d need to keep the ignition key turned to get it to fire up completely.

Once it was up and running, there didn’t seem to be any problem. Acceleration was normal and it would idle fine, except one time when it stalled and wouldn’t start again.

Anyway, as I mentioned, it has been absolutely fine since the field repair of this little filter. And, ya, I don’t think the 300TDi has the same part. But if you have a truck that has one and you need a new one, this is one of those strange times that the genuine part is ⅔ the price of the aftermarket part.

[Stu&Sly]

Wow Stephen great problem solving. Nice job.

[TD50below]

That's great info. Great detail and the pics are excellent. Thanks!