Be having a look at the fuel hoses to and from the tank ...

A pin-hole would let air in but might not give a tell-tale leak ...
 
Managed to confirm it really is loosing power/lacking power today going up 2 hills.

Took the bleed screw out of the fuel filter and pumped the lift pump manually to see if its the lift pump, the nice splurge I got out the top of the filter would suggest the lift pump is OK, though it took a few pumps to achieve, would that indicate air in the fuel system?

Took the turbo/FIP hose off too to check that for any obvious damage, the cable (not rubber) seems to be in good condition, no obvious splits and the like.

Unfortunately, in taking it off/putting it back on I think I've knocked a connection somewhere because now I just get a click when trying to turn it over:rolleyes:, didn't fancy going hunting in the dark/cold rain. I did give it half a second on the starter to be able to pump the lift pump so likely a fuse or something knocked loose by the turbo hose on/off.

Suppose once I sort that it may be a drain the fuel tank job.:(
Are you sure the lack of power is related to the wading and not just a coincidence? You say you've been lacking power at high revs for a while.
 
I think its coincidence but I think it can't be ruled out.

Also on the list is to disconnect the turbo from the FIP and see what effect that has.
 
starter motor solenoid wire?

And the winner is... yep, was solenoid cable had gotten knocked off. So now the noisy parts work again.:D

On the power loss front, checked the throttle cable adjuster and had a look through the top of the fuel tank, looked like nice clean diesel.

Took it out for a quick run to see if the power loss repeated again and if the turbo was working and managed to get power loss on the flat, followed by a full on engine stall. I twas also struggling to get to 40 in 3rd shortly before that so, based on the stall my thinking is going back to Lift Pump.
Think I might also look at replacing the fuel hoses just to as a matter of cause.
 
Changed the lift pump today, it doesn't seem to want to prime off the lift pump, think the foot is sitting a bit high on the cam, even at the lowest point but with the pump slightly out it does prime (tested it as a I was fitting it).
Took it for a drive and no repeat of sluggish or loss of power on the flat section from the other day, took it up a small hill I had loss of power on before and again no problems.

Tried a few hill starts too and managed to accelerate whilst on a hill too so short of trying a really steep hill (will be going up one Monday morning) not much more I can do to put it under loaded/demand fuel.
 

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