Scout Engine Replaced - Now Poor Economy

[lard-ajc]

Having replaced the scout's engine at 125k miles with a broken crankshaft I'm struggling to get the previous levels for fuel economy.

The new engine is exactly the same engine code (BMM) and has 40k miles on it. At the engine change we put a new cam belt on, new clutch and flywheel, fresh filters etc.

The old engine would comfortably get 48mpg (sometimes 53 on very gentle journeys) but the replacement is struggling to get 41mpg after about 300 miles. The engine feels like it's got more power (suspect compression is much better) but I'd like some of the economy back.

Is this something that will improve or might there be something else going on?

thanks

andrew

[Stormchaser]

Have you scanned it for any error codes?

Is the timing correct when you put a new belt on?

[Niall]

40k miles?

That's not even run in! Anecdotally I remember in the past on here 2.0PD 140 bhp drivers getting wildly different figures when contributing to the evergreen economy threads with no reason or rhyme. So hopefully you haven't got a low economy one!

Has the engine change shenanigans changed your insurance? Just hypothetically wondered "what would I do" if in the same position, as cost to change to another Scout would be more than the cost of a replacement engine and the Scout is so well suited to what I want from a car. Did you consider a 170bhp from an A3 quattro or Yeti donor, or is none of that as simple as I think it should be, before you even start thinking about insurance?

Niall

[lard-ajc]

Stormchaser: timing is right as we locked the pulleys in place before changing the belt (or does it need setting up via vcds as well?).  Not done a scan yet as I'm now on paternity so haven't been to work to borrow a cable yet...</p>

Niall: Have gone temporarily deaf re: ins!</p>

I considered a vRS engine but as I needed a relatively quick and easy fix (snow and imminent baby) I decided to go for a direct replacement to make sure there would be as few probs with the fitting as possible.</p>

Think the car would be perfect with the 170 bhp engine but should be relatively easy to chip this engine to the performance of the vRS (at a later date)</p>

Overall cost was £2000 (engine, new DMF/clutch, new cam belt kit/water poump and labour).  TPS in Leicester gave me very good prices on the parts and a good friend of my father in law is a Saab mechanic who is more than a bit skilled with a spanner.  9am on saturday to 1am on sunday got the job done.</p>

If I had to pay garage prices it would have been a bigger question of whether to bother.</p>

[Stuart_J]

Are you using the same injectors ?? If the new engine had bigger injectors it may give more power but use a bit more juice, You have a DPF I think so yopu wont be able to see a smokier exhaust, a sign of bigger injectors

Edited 22 February, 2012 by Stuart_J

[bfranc]

Stormchaser: timing is right as we locked the pulleys in place before changing the belt (or does it need setting up via vcds as well?).  Not done a scan yet as I'm now on paternity so haven't been to work to borrow a cable yet...</p>

Check for torque value in vcds, it must be 0.0 or -0.5 kw for better economy.

[lard-ajc]

Check for torque value in vcds, it must be 0.0 or -0.5 kw for better economy.

will have a look for that - any clues where I'd find it?

ta