Losing fuel prime

This is a preemtive thread to bounce ideas around and discuss while I wait for the opportunity to actually do some work on the 200tdi. I am having symptoms which I assume are a loss of fuel prime. It is taking longer to crank over before starting, initially when dropping to idle after revving idle seems to run rough and it will not pick revs back up, there is a distinct smell of diesel form the front end but cannot seen any obvious leak, once everything has settled down it then seems to runs quite happily.

Symptoms started on Saturday, on Sunday it happily drove 300 miles back from Scotland so once running it is not an issue. My plan for lunch time today is to replace the leak off pipes so see if they have perished and are letting air in and the fuel system bleeds down, and also to replace the lift pump to see if that helps with the rough running and not picking up revs.

There are no obvious leaks but there must be something to smell of fuel. I have still not got around to washing the engine bay after the oil cooler pipe split so everything is a little wet and oily. Is there anything other than the above that is worth doing to check things? The above I have parts on the shelf for and also carry spares on the vehicle after having issues previously so they are quick and easy to change out. Does anyone else have any other suggestions of things that might be a cause?

If fuel it's either fuel starvation or, as you say, a fuel leak/air being drawn in. Either way I'd be inclined to thoroughly clean the engine/engine bay before trying to fault find so starting with a clean inspection area. It'll only take an hour or so to give a thorough scrub up/remove all oil traces. A large can of Gunk/engine degreaser worked in, followed by a good wash off with hot soapy water and a thorough dry is what's needed.

Leak off/return pipes and lift pump with correct spacer would be my first starting points too + have you checked for blockages in the fuel lines and fuel tank? Blockages can cause a myriad of symptoms similar to what you're seeing.

v8250 said:

If fuel it's either fuel starvation or, as you say, a fuel leak/air being drawn in. Either way I'd be inclined to thoroughly clean the engine/engine bay before trying to fault find so starting with a clean inspection area. It'll only take an hour or so to give a thorough scrub up/remove all oil traces. A large can of Gunk/engine degreaser worked in, followed by a good wash off with hot soapy water and a thorough dry is what's needed.

Leak off/return pipes and lift pump with correct spacer would be my first starting points too + have you checked for blockages in the fuel lines and fuel tank? Blockages can cause a myriad of symptoms similar to what you're seeing.

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The reason it hasn't yet been cleaned is that the pressure washer packed up so am waiting to borrow one, but it is on the list.

I have not checked for blockages as once running smoothly it runs with no issues, like i said did 300 miles with it like that, but if symptoms persist after the swap out of pipe and pump it will be my next port of call.

Fuel filter seal is another spot where air can get in causing a drain back.

fuel leak off pipes are very common also

tottot said:

Fuel filter seal is another spot where air can get in causing a drain back.

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many thanks I will check that is tight was fitted a few thousand miles ago now although not that long in terms of time

Fit a facet pump off the v8 110. About £50 genuine part bypassed the lift pump. Not had any problems since.
Fitted to bulkhead for easy acsess to the removable filter on the base

Had a few lift pumps fail & caused bleed back

Hicap phill said:

Fit a facet pump off the v8 110. About £50 genuine part bypassed the lift pump. Not had any problems since.
Fitted to bulkhead for easy acsess to the removable filter on the base

Had a few lift pumps fail & caused bleed back

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I have had several lift pumps fail which is why I now carry one in the vehicle, I am hoping that is my issue, the one fitted has only been in use about 12 months old but has done about 30k

Hicap phill said:

Fit a facet pump off the v8 110. About £50 genuine part bypassed the lift pump. Not had any problems since.
Fitted to bulkhead for easy acsess to the removable filter on the base

Had a few lift pumps fail & caused bleed back

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@Hicap phill , do you know which Facet model number this is? I'm using Delphi lift pump and this changeover keeps tapping me on the shoulder as it makes much sense rather than having a lift pump fail at an irritating moment/on shoulder of M4/half way up a mountain.

eta

This one - if so, it seems a bit overkill as a lift pump? https://www.lrworkshop.com/parts/PRC3901

v8250 said:

@Hicap phill , do you know which Facet model number this is? I'm using Delphi lift pump and this changeover keeps tapping me on the shoulder as it makes much sense rather than having a lift pump fail at an irritating moment/on shoulder of M4/half way up a mountain.

eta

This one - if so, it seems a bit overkill as a lift pump? https://www.lrworkshop.com/parts/PRC3901

View attachment 318245

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That’s is the correct part number. I got mine from a LR Indy. & it was a lot cheaper than fleabay. It’s exactly the same as a facet just not branded up.

Try ridgeway 4x4 Swindon to see if they have some on shelf & price.
It’s the only place I can go and search through books for parts to cross match.

Well quick update replacing the lift pump did not solve the issue but made a noticeable difference so the one fitted was certainly on the way out. leak off pipes are next when that arrives, what I thought was leak off pipe on the shelf was washer pipe! hopefully that will be the solve.