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I started to back off at 114 (gps) as a 3 lane motorway was seemingly too narow ! ............... also about 90 in 4th.............

It will only pull to just over 98 (gps) with 35 x 13.50's on............................

:)

Ian

^^^

Been there tried that, damaged both of our respective underwears at early dawn on disengaging warp on dual Carridgeway,

passenger, who was helping me data log, and I, agreed never ever ever again to try to find Max Speed in 5th :ph34r:

2 ton-ish, the aero dynamics of a small bungalow, and on Simex and a JED V8 = Trip to M&S underwear Dept :lol:

Nige

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Marek's 200Tdi 90 on 235/85 tyres used to go about 80 mph max and felt really sluggish (the white soft top we had at 7S last June).

Then we found the cone on the diaphram in the fuel pump was well worn causing massive under fueling. A very slight turn on the diaphram caused a dramatic improvement - better reponse and drivability and now up to 95mph (tested on private roads :P ). It's worth checking.

Oh, I've had 115 out of my Td5 Disco - that's what aerodynamics will do for you :lol:

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The diaphram and star wheel have already been turned 90 dregrees, but i'll take it out and have a looksee.

We found a well worn groove on the cone where it actuates the rack, or what ever it is, a slight turn moved the worn part away from this and made the improvement. If you've turned the diaphram already then this shouldn't be an issue, but have a look see. With a 90 degree turn on the diaphram and 90 degrees on the star wheel you should definately be getting better performance than this, so I'd be tempted to look elsewhere. Try (some are mentioned above):

Stuck waste gate, actuate it a few times with a spanner to free it up

No boost - siezed turbo from water ingress or cooked bearings, damaged turbo vanes etc.

Lost boost through split pipe, intertcooler etc.

Low compression - check valve clearances and check crank case pressure by running it with the oil cap off

Fuel pump timing / cam belt setup - this would also give very poor pickup

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TBH if you got a 200tdi 90 that'll only do 74 then theres something wrong.

Do you get a sound that seems to be rattley tappetty at about 2500 rev's ( may only happen when the engine is warmed up)

If so then your fuel lift pumps arm has disconnected from the lift pump.

Also worth disconnecting the outlet pipe from the lift pump and giving the handle on the lift pump a few ups and downs to see if any fuel comes out. If no fuel comes out then either the arm has disconnected itself or the diaphram is goosed.

Thats my best guess especially if your not smoking excessively.

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make sure that the accelorator cable is moving to its full extent. Under the bonnent at the end of the outer cable, there is a knurled threaded adjuster, turn this anti-clock until the revs start to pick up, could be a bit of slack in the cable. sometime people wind it in at mot time, so that it doesnt get anywhere near max rpm, more like 2/3.

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well i took my 90 out with it's new gearbox and disco transfer box i was sitting with the speedo at 60 and was flying past the lorrys at 65 i was passing the slower cars(i've owned the 90 for almost 7years and this is the first time i've got to overtake something other than tractors :P )

before i put the props on i got it up to 98mph (so no load ) but i cant see me going faster than 70 on the road any way

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at 70'ish with the overdrive disengaged [out]rpm is around 3000 with overdrive engaged [in] about 2500, IIRC. my overdrive drops the revs by 500 to 600 for any speed when engaged.

for example ---

at 60 overdrive out rpm 2500

22.jpg

at 60 overdrive in rpm 2000/2100

23.jpg

if its any help my 200tdi disco will do 75 on a field :ph34r: but i have nover toopped it out

mikey

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I've been having a tinker but still no joy, adjusted the throttle cable, removed and checked the intercooler pipes, checked the small pipe from the turbo to pump, checked the valves, inspected the diaphram cone, checked pump timing and a general check over of everthing else. It all looks fine to me :angry:

I'll try and buy a boost gauge next week to see what thats doing.

Any other ideas of what else to look at ?

Something which may be of importance, it's drinking a lot of diesel at the moment , about 20mpg on the motorway :blink: even since i've put a disco transfer box back in to drop the revs. it used to do 27-30mpg even with the roof tent on.

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I have noticed over the last couple of days it is smoking a bit even though i've turned the pump back a fair way. A car was following me closely early this morning and his headlights lit up quite a trial of smoke :blink:, i can only see black wispy smoke when accelerating or the engine is working hard in the daylight.

Any sugestions as to what is broke / about to

symtoms :-

excess black smoke

drinking fuel

underpowered - particularly after 60mph

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All oils and filters changed a few hundred miles ago, just checked the air filter and all the intake hoses and they are as new.

Boost gauge should be here and fitted next week.

could old / knackered injectors cause these problems ?

Check that the wastegate actuator is connected and working.

the circlip on mine came off once :rolleyes:

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TUNE IT, no smoke no poke lmao

all i can really think of is intake and thats already been said,

try to clean out the intake manifold as it may be blocked or semi blocked with grease and gunk, also have you checked the intercooler?

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The actuator is conected.

I've installed the boost gauge now, and it's reading 0.7 bar with my foot to the floor going up a small hill.

Any sugestions as to what needs adjusting / replacing :unsure:

that's a bit low, 200Tdi should give 0.80 to 0.85 boost, maybe the actuator rod needs a tweak or the sensing line has a pin hole in it.

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