Hi,
I have a 1996 Disco I which will pull around 450 miles on a full tank of Diesel (around 22/23mpg). When I bought the car a few months ago, the garage told me that I should expect 34ish to the gallon. Is there something wrong with my engine, or was the garage being a little over optimistic for these series of engines (300tdi)?
It smokes a little when cold, but once warm there is no smoke whatsoever.
Thanks!
|| Hi, || || I have a 1996 Disco I which will pull around 450 miles on a full || tank of Diesel (around 22/23mpg). When I bought the car a few || months ago, the garage told me that I should expect 34ish to the || gallon. Is there something wrong with my engine, or was the garage || being a little over optimistic for these series of engines (300tdi)? || || It smokes a little when cold, but once warm there is no smoke || whatsoever. || || Thanks!
If it's an auto, then that is exactly what I got from mine - 22.9 mpg over all types of driving. I would expect a little more from a manual - around
25-ish, although people's experiences seem to differ. If he told you 34, he's pulling your plonker. I have heard of people getting 32-33ish, but they are usually 200Tdi manuals, on long runs and the like. I doubt if there is anything wrong with your engine.Using this,
Sales man well optomistic!
On my 96 disco 300tdi i get between 28 - 32 mpg. over the winter is when it drops to 28. i do drive conservatively and try to keep to 50 mph on average,
60-65 on motorway.paul.
Thats about all I get as well. to be honest I could almost get a V8 to return about the same!!!
On or around Sun, 16 Apr 2006 15:15:16 +0100, "Richard Wilkinson" enlightened us thusly:
On the low side for a manual, if that's what it is. we get about 28-30 on average, except if you hammer down the motorway at 90, or tow a big trailer.
On or around Sun, 16 Apr 2006 17:50:32 GMT, "Vince" enlightened us thusly:
says he... I never got more than about 18 from the 3.5 V8 disco, although a gently driven 3.9 can sneak over 20.
a lot of TDis are not really very well tuned. Ours was significantly better after fettling it - more power and more economy, can't be bad. Oh, and the non-cat pipe helps too.
Hi iv got an auto rangie 300 25mpg is tops
Hi,
I have a Disco 2.5TDI XS 300 series Auto. I was getting 18 mpg around town and noticed that the air filter was absolutely filthy, I changed it. On a round trip of 600 miles over three days that has now gone upto 28 m.p.g. You might push it up to 30 with a K&N Filter and a Hi Clyclone. Around town I am hitting 24 m.p.g.
On a 200TDI 110 CSW I got 34 m.p.g over 4771 in three weeks but that was averaging 45 miles per hour doing 300 miles per day.
Andy
There we are - 18 is not THAT far away from 24mpg - the TD5 auto discovery I had for a while was only doing 20mpg - maybe it's the way I drive.
On or around Sun, 16 Apr 2006 22:27:22 GMT, "Vince" enlightened us thusly:
yeah, but 24 for a manual disco TDi in normal use is low, you should get at least 28, really more than that. The TD5 is noted for being a bit more thirsty.
Likesay, in ordinary non-hammering use ours is returning over 30.
Ill try changing the air filter, it looks a bit grubby and clogged.
Is there anything else i can do to "tune" the engine? (without going over the top and modding the engine)
Thanks!
On or around Mon, 17 Apr 2006 18:52:28 +0100, "Richard Wilkinson" enlightened us thusly:
Apart from the air filter...
hmmm. I saved this lot somewhere... aha:
================================================================== disclaimer: If anything you do following reading this breaks your engine, don't come crying to me. You do this type of stuff at your own risk.
First service the engine, including air filter, diesel filter and valve clearances.
Then check that when you put the pedal to the floor it does actually open the pump to the stop - the cable can be slack, if so, take up the slack in the cable, till there's just a little bit of free play with the throttle pedal released, to make sure it goes back to idle properly.
Next check the free-revving speed: make sure the engine's thoroughly warm and has plenty of oil; as per the MOT smoke test, which is basically what you're doing. Floor the throttle, wait for the engine speed to stabilise (takes about 2-3 seconds), note the RPM and release the throttle. You need a rev counter for this, which is no problem on the disco. It should do about 4500 rpm. You can set it to just under 5000 without apparently harming things; though of course you don't rev it that hard in normal use. Do this by moving the maximum speed stop on the pump, which is the stop which the pump lever hits when it's "open". Move it a little at a time and check the revs you're getting. Note that it has a seal on it, you'll have to remove that. If that bothers you, leave it alone.
Having done that, instruct an assistant in the technique of doing the revs thing, and watch the exhaust (or put a mirror up so you can see the exhaust, I guess - if the exhaust comes out sideways you can see the exhaust in the driving mirror. Rev the engine as before, let it idle for a few seconds, then repeat, and look for smoke. If there's a lot of black smoke, it's running too much fuel; if there's no obvious smoke it can be turned up. The fuelling adjuster is on the "back" end of the pump, i.e. the opposite end to the pulley. The adjuster comes out parallel with the fuel outlet pipes, above them and towards the off side of the vehicle. It has a 13mm locknut, and a threaded rod which protrudes, the end of the rod has a 6mm hex on it. There will be some kind of seal on the adjuster, which may hide the locknut. slacken the locknut and then turn the adjuster in by no more than 1/4 turn, re-tighten the locknut and look for smoke as before. You're aiming for a situation where there's a slight amount of black smoke as the engine is accelerating, but no obvious smoke once it's up to revs. If you get a lot of smoke, you've gone too far, so back it off a bit. The adjustment is quite sensitive, a quarter turn is usually enough.
If you have a friendly MOT garage, you can do the last phase with the aid of the smoke checker for MOTs, and make sure you've got it nicely below the MOT threshold; otherwise, you may fail the test. In the event of it being slightly too smoky on test, the best bet is to back the maximum speed off to the book value of 4500, which will probably solve it - if it doesn't, then you've over-done it on the fuelling adjustment anyway.
The point about adjusting the maximum speed is not to allow it to rev very fast on the road - it improves the mid-range performance at full throttle, by allowing the pump to "open" slightly more. Some people will tell you this doesn't happen, but I go with what I've experienced.
Having done these things, It should be going OK. If it still lacks power, then you need to consider whether there's anything else wrong with it. One thing that can affect power is a dirty intercooler. The intercooler can get partly blocked inside with nasty oily stuff. If you don't seem to get much power when it should be "on boost" (i.e. over about 2000 rpm) then this is worth checking. The same symptoms can be had from low boost pressure, but this is one thing you do need the right gear, i.e. a pressure gauge and adaptor, to check.
On some TDis, there is an EGR valve. This can stick open, causing exhaust gas to enter the inlet manifold when it shouldn't be. Personally, I blocked it off on the one we run.
A final point is pump timing. On the one we have, I recently replaced the timing belt and took good care to get the timing aligned as per the book. This engine has always felt rather "flat" in initial acceleration. Experience on petrol engines led me to wonder if it was a bit retarded, so I tried advancing the pump timing a bit. You'll want the various kinds of timing pins to do this. If you're not happy messing with the pump timing, then get someone who knows what they're about to do it for you. I advanced ours by something around 6 degrees (didn't measure it, natch) and it now seems to pick up more briskly. Don't overdo it.
My Defender was rebuilt using the running gear and 300TD1 engine from a Disco ten years ago. The black smoke on start up is normal, so only worry if you don't get it. My consumption hovers just below thirty, 27-29 MPG, but I've also noticed that it doesn't vary when I'm fully laden with roofboxes etc, although I suspect this has more to do with the lack of aerodynamics of the original vehicle. Cheers, John
Thanks for that Austin.
Our 1991 Disco 200TDi manual averages about 30 mpg. It seems the auto versions are lot thirstier. Pushing them too hard also makes a lot of difference. Ours is 'cruised' gently and that's not so slow either, more or less keeping to the speed limits seems to give reasonable economy.
By the way, she's for sale;
144,000 miles only, Gold, 5 doors, 7 seats everything in good order except central locking now changed to manual locking.New MOT last week
£1,650 ono.Vehicle located at
My Disco L reg 300tdi Auto, if i fill the tank and drive it until the low petrol light comes on it gives me without fail between 500 to 525 miles i have checked the speedo with the gps and this is correct, i am not particularly easy going with the right foot either. GGJ
Interesting, you're running this TDi on Petrol?
good point, should have said fuel light :o)
GGJ
Not really, I'm just a sad picky bastard!
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.