Poor MPG

[charvell]

get a 3rd Gen I get 50+mpg around town.

really what the hell am i doing wtong in my truck then

[Bear Ona Bike]

I've found the best way to get excellent mpg out of a Surf is to assume that just because the dealer stuck an MPH facia on the speedo that the odometer is still in KM and not MILES!
Hell! I was getting over 30mpg for ages until I twigged that the earth must have shrunk!

[The Pope]

mpg

I live and work in South France, coming back to UK about 4 times a year. I average 32.7mpg , thats travelling at a steady 80mph ( 130kph) on the motorway leg of the journey.
Around town about 26mpg.
Thats in a 1997 3rd gen 3lt turbo.
No mods, just oil and filter changes about every 6000miles.
Had it for about 6 years now and completely trouble free.
Having said that I think it has just developed saggy arse syndrom, only noticable with rear passengers over speed bump things and pot holes.

[MattR]

Sussed it (hopefully

Having changed the tranny oil and fitting a new thermostat, decided to take the head off and have a look. Found cracks between 3 of the cylinders.

Just been to collect new head from guy on ebay and will fit it tomorrow and ley you know if the MPG gets better.

Symptoms were pressurisation of cooling system even when cold.

Now, where can I find the head torque figures and tightening sequence...?

[Wolfracer]

I've found the best way to get excellent mpg out of a Surf is to assume that just because the dealer stuck an MPH facia on the speedo that the odometer is still in KM and not MILES!
Hell! I was getting over 30mpg for ages until I twigged that the earth must have shrunk!

Just to clarify then, the speedo's in MPH. but the Odometer is in Km, is this correct? your post reads that the odometer is in Miles, if so, mines done 225k miles!!!!

[Hazzo]

I reckon I get between 29-32 on the mway by pi$$ing off everyone and doing a steady 57mph, around town its nearer 20-25. H

[MattR]

Head change

Took me all day to get the old head off (what a bast*rd) got the new one back on and then read a post by Tony (I think) that said not to use the old head bolts. The guy who sold me the head told me I could use the old ones again, but it didnt ring true....

Anyway, just waiting for Roughtrax to deliver the new bolts now.

Ive had the Surf for about 6 years and i was going to get rid of her this year and get something that does better MPG. But I'd have to spend £8 to £10k to get anything worthwhile and thats an awfull lot of diesel!

So I decided to treat the old girl to a new radiator as well!

With a new head, new cam, new radiator, new thermostat, new water pump, and an oil and filter change, I should be looking at MPG well into the 20s!!

Happy days....

[Hazzo]

I wouldn't bank on it unless your getting a new fuel pump and injectors too, then drive like a ladeeeeeeeey. H

[MattR]

Head Change

I was trying to be positive and upbeat....

[Hazzo]

I know, just peeing on your fire, hope it pans out for ya, mine seems to be even better since the new head and EGR blocking plates, round town, though mway no difference. H

I am driving like a bird though till I change oil/filter at 1000miles, my run in the head period.

[MattR]

What is the function of the EGR blocking plate?

[Hazzo]

After stripping the head off I set about cleaning all intakes etc and found them pretty well choked up with tar/grease/gunge/soot I put this down to the exhaust gas recirculating valve/pipe, I'd seen many here and other forums blocking this off as it cuts down on bad smokin diesels but imo, and mine was never smokey, having clogged engine intakes would cut down on the oxygen getting to the chambers, cool air, then it gets mixed with exhaust gas does not seem to me to be too good for the motor so I followed others here and elsewhere, made up plates n blocked the pipe off at both ends. I've left all the bits in place so it looks stock but basically its disabled now. H

[MattR]

I dont follow your logic. One the one hand you state the importance of unblocked pipes to keeping inlet gas temps down and then you go and completely block off the bit of kit specifically designed to promote cooler manifold temps!

Like you, my Surf doesnt smoke much so I'm happy to retain the EGR for now.

It peed down with rain last night so I didnt get to finish the job, but the new head is back on now and I should get the job finished tomorrow.

Anyone know what run in a new cam shaft requires? I guess I shouldnt let it tickover too slow for a while?

[Hazzo]

My surf doesn't smoke, period. I've also read about the cooling properties of red hot exhaust gases on combustion and don't buy it.

The logic is a clean engine will run better than a skanky one, cooling I've sorted, tar/soot and exhaust gas I can do without, I've been through threads here/Aus/SA etc before shutting down the egr and drawn my own conclusions as to why I don't want it, if you'd seen the intake manifold before I cleaned it out I think you'd have shut it off too, a globule of that gunge being sucked into a pot would imo act like grinding paste on the rings and sleeves making for a bottom end rebuild too. Anyway, mine runs fine, doing a steady 25-30 mpg, at sixty uphill sits at 90deg and normal at 85, which, as far as I'm aware is the running temp of this and many other diesel trucks, re a mechy mate, so I'm quite pleased with what I've done and the reasoning behind it. H

[MattR]

Good arguement, well presented.

I hope to get mine finished today and I'll let you know how I get on. My manifold didnt look too bad so I'm going to leave mine standard for now.

Any idea wher I can find a diagram showing where all the vacuum pipes go?