Defender 90 - 200TDi losing power

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
Ok I will change out the filter.

Prepare for a dumb question - it's just a pickup in the tank, line goes through filter, then to lifter pump and then to the injector pumps? If so is there a process for checking each part of that system other than just banging on the new filter and seeing if I break down again? Lol

Yes its thats simple, I think pipe goes to lift pump first then the filter? the slightest imperfection in any joint will let air in, the ve pump can handle a little air but to much will stop any diesel engine.
Sounds daft but have you checked the thottle linkage to make sure the injection pump lever is actually hitting the stop at full throttle? floor mats can effect this as can cable adjustment.

Older cars rot out the fuel pick up pipes, the pick up pipes can fracture, there may be a bit of plastic in the tank making its way to the pick up and blocking the pipe engine cuts out suction stops plastic floats away and all appears normal on inspection, kinked pipe, the list is endless, but the mk1 eyeball will see any issues.
Basically take nowt for granted, worst case scanario is the inj pump has an internal issue, but if you check all the basics thoroughly you can then be sure the only thing left is the inj pump.
 
Last edited:
Ok I will change out the filter.

Prepare for a dumb question - it's just a pickup in the tank, line goes through filter, then to lifter pump and then to the injector pumps? If so is there a process for checking each part of that system other than just banging on the new filter and seeing if I break down again? Lol
Yes. The beauty of these is that they are simple.
Some people cut into the fuel lines, and put a bit of clear plastic tube in the line, so you can see any air in the system.
I wouldn't bother unless you are regularly unable to start the vehicle in the mornings.
Having given this some thought, are you sure that the lack of acceleration isn't caused by the temperature?
The oil in the diffs and gearboxes is going to be pretty thick in those conditions, and they are not a very powerful engine anyway.
 
Hey guys, so before I put the new filter in I was hoping it would have the same symptoms as before. But in driving it around until the temp came up a bit it showed no signs of any surges/drop offs in power.

It is a lot warmer today than earlier in the week and I have been storing it in a heated garage so the conditions are nothing alike.

Some things I noticed - it only took a few seconds cranking the motor over to start, despite the filter being drained. So the lift pump seems to be ok - I was assuming it would take quite some time to prime if the lift pump was iffy.

On the temp potential root cause - it ran fine the the other day until the power dropped off, and then it would come back, go away again etc. If it was a sludgy trans/diff issue then I would expect the sluggishness would be consistent.

As for fuel line blockages - a similar thing happened about a year ago when I last changed the lift pump and filter. Prior to doing that I inspected the tank, pulled the pickup out etc and it looks really good in there surprisingly.

So my thoughts are - maybe it was

- A temporary blockage
- Some temp related issue with the fuel (not sure what)
- an intermittent lifter pump
- an intermittent injector pump

I guess the only thing I can do at this point is drive it about a bunch?
 
Heated fuel lines were a land rover option, maybe something to consider, or maybe even insualate them?
Some other make sof cars had heated filter heads using the engines coolant, Renault being one I can remember seeing.
I would hazard a guess some of your domestic cars have heated filter heads?

http://www.biotuning.co.uk/ShopFilters.htm
 
Last edited:
Heated fuel lines were a land rover option, maybe something to consider, or maybe even insualate them?
Some other make sof cars had heated filter heads using the engines coolant, Renault being one I can remember seeing.
I would hazard a guess some of your domestic cars have heated filter heads?

http://www.biotuning.co.uk/ShopFilters.htm


Wow so could the diesel in the lines just be too cold to combust properly? It was super cold that morning to be fair...

This is my first diesel so my knowledge of these aren't the best.
 
Wow so could the diesel in the lines just be too cold to combust properly? It was super cold that morning to be fair...

This is my first diesel so my knowledge of these aren't the best.

Nowt to do with the combustion side, Im sure Turboman mentioned it earlier on and its called diesel waxing, basically it gets so cold it goes semi solid and does not flow.
Hence the heated fuel lines and or heated filter head idea.

Only personally seen it once in the UK and that was about 20 odd yrs ago in Kent of all places.
Defender worse than normal cars as the whole underside is exposed as are the fuel lines.
 
Nowt to do with the combustion side, Im sure Turboman mentioned it earlier on and its called diesel waxing, basically it gets so cold it goes semi solid and does not flow.
Hence the heated fuel lines and or heated filter head idea.

Only personally seen it once in the UK and that was about 20 odd yrs ago in Kent of all places.
Defender worse than normal cars as the whole underside is exposed as are the fuel lines.
We used to see it a lot on Series and old tractors, especially when were working in the North, but on occasions in the South as well.
It was usually caused because farm storage tanks where we were working still had summer diesel in them, even if they had been topped up with winter diesel, it was still diluted by the stuff that was still in them.
If we had any, we used to put diesel additive in the tanks.
If we didn't, a gallon of normal petrol in the tanks used to deal with it.
 
We used to see it a lot on Series and old tractors, especially when were working in the North, but on occasions in the South as well.
It was usually caused because farm storage tanks where we were working still had summer diesel in them, even if they had been topped up with winter diesel, it was still diluted by the stuff that was still in them.
If we had any, we used to put diesel additive in the tanks.
If we didn't, a gallon of normal petrol in the tanks used to deal with it.

Remember my FIL telling me when winter came along (50 odd yrs ago maybe longer as hes 85 now) they used to get some sort of winter additive and pour it into the underground fuel bunker otherwise the trucks ground to a halt.
 
Remember my FIL telling me when winter came along (50 odd yrs ago maybe longer as hes 85 now) they used to get some sort of winter additive and pour it into the underground fuel bunker otherwise the trucks ground to a halt.
The one we used to use was made by Case, we got it from the dealer. As far as I know, the additives are still available.
Maybe not of much use around you, but well worth it in colder climates.
 
The one we used to use was made by Case, we got it from the dealer. As far as I know, the additives are still available.
Maybe not of much use around you, but well worth it in colder climates.

I think with the advent of common rail, cold diesel isnt such an issue once the engine is running.
 
So it's above freezing today, took the land rover out and it was fine for about 3-4 miles or so (basically same as before) and then it started surging a little.

So I figured I should swap the filter and then try again. With the new filter is still had the problem - even to the point of the original situation where it went to idle and I couldn't get revs at all until then I got fuel pressure back and it was ok again.

I'm guessing my next step is to swap the lift pump and try again?
 
So it's above freezing today, took the land rover out and it was fine for about 3-4 miles or so (basically same as before) and then it started surging a little.

So I figured I should swap the filter and then try again. With the new filter is still had the problem - even to the point of the original situation where it went to idle and I couldn't get revs at all until then I got fuel pressure back and it was ok again.

I'm guessing my next step is to swap the lift pump and try again?
That would probably be a good idea. And they are cheap over here, don't know about there.
It used to be possible to get a kit, with a new diaphragm and valves, so you could rebuild the old one, they just come apart with screws around the rim.
I don't know if they are still available, though, the pumps are quite cheap so I don't think people bother to rebuild them now.
 
That would probably be a good idea. And they are cheap over here, don't know about there.
It used to be possible to get a kit, with a new diaphragm and valves, so you could rebuild the old one, they just come apart with screws around the rim.
I don't know if they are still available, though, the pumps are quite cheap so I don't think people bother to rebuild them now.

Sadly I think they are all now crimped throwaway jobs, I used to hate repalcing them stupid little poppet valves inside the rebuildable ones, used to drive me nuts!
 
So I put in the new lift pump and it's still got the same problem.

Best way to witness it is when the engine is running, in neutral, hold the throttle at 50% - the revs climb as they should and hold steady for 10-15 secs or so and then they will fall until the engine falls below idle and you can see the whole block shudder as it misses and stumbles. At this point releasing the throttle allows it to come slowly back to idle. At which point you can just keep doing the same thing.

So with a new filter and a new lift pump... Running out of ideas or things to check. Any thoughts?
 
So I put in the new lift pump and it's still got the same problem.

Best way to witness it is when the engine is running, in neutral, hold the throttle at 50% - the revs climb as they should and hold steady for 10-15 secs or so and then they will fall until the engine falls below idle and you can see the whole block shudder as it misses and stumbles. At this point releasing the throttle allows it to come slowly back to idle. At which point you can just keep doing the same thing.

So with a new filter and a new lift pump... Running out of ideas or things to check. Any thoughts?

Did you pull the stack pipe and check it?
Are you sure there is nothing foreign in the fuel tank itself?
Have you checked all the fuel lines and connections, and replaced the sealing washers?
Have you removed the stop solenoid, gutted it (just a spring and plunger) and refitted it, then tried your test again?
On the inj pump the fat pipe/banjo at the front is the main feed and the banjo at the rear is the return, the return banjo itself is special and has a restrictor built in to maintain the internal fuel pressure in the pump at (I think) 60/70psi, might be worth a look see?

I can remember a guy on here a few years back having weird fuel issues on a 200, and it was his fuel return line to the tank was blocked, must be a super rare fault but again got to be worth a look and blow it all through?

If you have done all of that and it all checks out, it could be your injector pump, which sadly is not cheap, on the upside the VE inj pump is fitted to all sorts of kit including the old Cummins 6bt, which you will have loads of over there, so the diesel shops will have access to any parts needed.
 
So I checked that the solenoid was functioning, and wobbled the connector about a bit to see if it intermittently worked but it seemed fine.

The feed to the injector pump is good, I will check the rear.

One other thought was whether I should fill a jug with some fresh diesel, and run my lift pump feed to that jug and see if it still shows the issue. At least that way I can identify if it's no problem pre-lift pump?
 
Hey guys, what's this little wired unit next to my fuel tank?
 

Attachments

  • IMG_20200208_110349.jpg
    IMG_20200208_110349.jpg
    446.4 KB · Views: 99
So I checked that the solenoid was functioning, and wobbled the connector about a bit to see if it intermittently worked but it seemed fine.

The feed to the injector pump is good, I will check the rear.

One other thought was whether I should fill a jug with some fresh diesel, and run my lift pump feed to that jug and see if it still shows the issue. At least that way I can identify if it's no problem pre-lift pump?

How did you actually test the stop solenoid?
 
Back
Top