Yes..just had a crackin chat with Adz..looks like my gearing is out with the combo i have, disco TB with 235/85/16 AT's.
Thats one of the problems anyway!!
Hi Storm,
Your gearing setup (taking your transfer box and wheel / tyre diameters into consideration) shouldn't really be holding your engine back all that much. I have a 200tdi hooked up to an lt77 on the standard Defender transfer box with 235 x 85 x r16 tyres and it absolutely flies. I have achieved 40.02 MPG on a steady run across the country (averaging 50mph) and 27-28 MPG on work / local runs. On motor way runs between Leeds and Ipswich (220 miles) I can achieve 35-37 MPG and it will sit happily at 65 - 70 MPH with the standard Defender transfer box, but will reach 85 at a push. It will also accelerate from 0 - 60 in around 17-19 seconds which is exceptional as far as I am concerned. I have driven a Defender with a 200tdi Disco transfer box and 235 x 85 x r16 tyres and it almost matched my motor, albeit being a little slower on take off - but not so much a dramatic difference. Unfortunately I can not comment on its performance on the motor-way because I only took it down the local bypass.
I think that you need to be testing various things your self before you start paying your local mechanic a shed load of money. Here is a list that might just help you along, starting with the basic things and then working through to the more complex things, all of which are FREE. If you follow this, you should have a given your engine, fuel and air delivery system a thorough inspection and if nothing comes up, then you should be tempted to look into compression / leakage testing:
Fuel:
- Remove pickup pipe from fuel tank and check for blockages.
- Examine pick up pipe for pin holes / rot that will allow air into the fuel
- Follow fuel line from tank to lift pump ensuring pipe is not kinked / collapsed
- Ensure no leaks in fuel line between pick up pipe and lift pump
- Ensure no leaks in fuel line between lift pump and fuel filter housing (replace copper washers)
- Ensure fuel filter is not clogged
- Ensure no rubber seals from previous fuel filters are stuck to fuel filter housing
- Ensure fuel filter housing is not cracked on top
- Ensure 10mm bleed bolt on top of fuel filter housing is secure with copper washer
- Ensure no leaks in fuel line between filter housing and injection pump (replace copper washers)
- Ensure injector pipes are not leaking / weeping fuel at connections
- Ensure injector pipes are not perforated which will allow air into fuel
- Ensure spill rail banjo bolts from injectors are secure (replace copper washers)
- Ensure spill rail rubber pipe work is tight on banjo nuts and not brittle / split
- Remove and inspect filter mesh and pin hole in fuel return bolt from injection pump (replace copper washers)
- Ensure no leaks in fuel return line
Air:
- Ensure air filter is not clogged / damp
- Ensure CAF (cold air feed) pipe between filter and turbo inlet is not collapsed
- Ensure boost pipe between turbo outlet and intercooler is not collapsed / loose
- Ensure intercooler is clean (use paraffin)
- Ensure intercooler is not split / perforated
- Ensure boost pipe between intercooler outlet and inlet manifold is not collapsed / loose
Engine:
- Ensure lift pump is working correctly (should throw fuel at bonnet with pipe to filter housing removed)
- Ensure valve clearances are set correctly (.20mm / 8 thou)
- Ensure injection timing is not retarded (can be done by removing inspection cover or timing case)
- Ensure plastic pipe between turbo and injection pump is in situ and in good condition (replace copper washers)
- Ensure turbo oil feed / return lines are clear
- Ensure turbo waste gate is not stuck open
- Ensure turbo waste gate actuator arm is connected
- Ensure fuel pin under boost diaphragm in injection pump is not seized
And that's all I can think of for now. If there's anything you want further information on, just ask!
-Pos