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petrol usage

Started by Maat1985, 31 August 2009, 06:52 AM

Maat1985

i was just wondering everyones experience on driving how much petrol they use.....
atm my odo doesnt work sop dunno how many km's i can get from my petrol but so i will just refer to engine revs....

at 50 - 60kms is what i find the best in my 280se as this is bottom of 4th gear and it is 1500 - 2000rpm
accelerating when in drive at any point never goes above 3000rpm which is great.....
70 - 80kms is around 2000 - 2500 rpm.... and accelerating is never many more revs than cruising unless i give it a bootful and kickdown gears....

however the prob i find is because of the gearbox and the diff i assume..... at 120km/h it is sitting on 3500 rpm because it has been in 4th for the last 60km/h and the ratio in the diff is quite high i think..... and this really chews the petrol i nthink i used somewhere between 1/3 and 1/2 a tankl on a 45min freeway drive.....

and i know there is nothing i can do about this without losing acceleration just wanted to know everyone elses experiences and at first i thought i could never afford to drive a v8 but now i really think i can cus this thing does guzzle the gas.... not so much round the city at 50 - 70km/h but on the freeway jeez it is bad......
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

Big_Richard

my 6.9 has allways done between 400 - 500 k's per tank, and I'm certainly not gentle on the throttle. All w116 fuel tanks are the same size.

I'm lead to believe 280 - 6.9 is irrelevant in terms of fuel consumption, because they are all simply atrocious. They are incredibly inefficient transport devices with all that metal - have you ever tried picking up just one bumper ?? ;)


another sad 280s

don't forget that the petrol guages on these aren't linear. secondly if you honestly used that much then something is seriously wrong

Maat1985

i know my car is running slighlty rich but jeez cant make that much of a difference..... i need a new manifold pressure sensor..... and that drive was sitting on 120km/h steady for almost the whole way.....
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

another sad 280s

get them done and then judge it properly. with my poorly tuned 280s i was getting between 17-20L per hundred. 500-600km per tank

oscar

A new MPS Maat?  Was it yours that might have been tampered with? ie adjustment screw possibly adjusted previously?  PM 13B and see if he has any left, he had a couple of spares a while back.

IMO just about all w116's could've benefited from an overdrive in the driveline for those long cruises on a fwy or hwy.  My 350 is no different, doing 120km/h the revs are up there at 3500 or so and you just wish it could change one more time. 

The only way you could economically introduce some economy for the hwy Maat would be to throw on a used shorter diff from a 350 or better still a 450.  Of course your speedo and odo will read wrong but in real terms your revs will be lower at cruising speeds and fuel consumption would drop.  Your take off speed would be lower round town and whether that would lead to too much labouring and worse economy for city driving I don't know.
1973 350SE, my first & fave

s class

My daily mix is a combination of traffic and freeway driving at 4000rpm-plus in my 280SE K-jet.  I usually drive pretty hard, and get about 600km on a tank.  If I do more traffic driving, and if I drive hard it can get as poor as 580km per tank.  If I'm on the open road only at 4000rpm plus, it can get as good as 625km on a tank. 
Some 280SE owners have reported over 700km on a tank with sensible driving (100km/h crusing).

The 6.9 gives me 450km on a tank if used in anger, and 530km on a tank of fast highway driving.

Be aware that out-of-tune D-jet 280's can really chew fuel.  I know of a few that can only get 250 to 300km on a tank.  But on the other hand, when sorted, the D-jet should be more efficient than the K-jet. 


[color=blue]'76 6.9 Euro[/color], [color=red]'78 6.9 AMG[/color], '80 280SE, [color=brown]'74 350SE[/color], [color=black]'82 500SEL euro full hydro, '83 500SEL euro full hydro [/color], '81 500SL

Papalangi

I can't figure how to convert MPG to metric but my 1976 450SEL (M117) gets 13 MPG, the 1971 250C (M130) got 15 MPG and the 1976 280C (M110) got 14 MPG.

My 1974 Ford F250 may get as much as 9 or 10 MPG.

Michael
'83 300SD, I'm back!  It's the son's new car (12/2020)
1976 450SEL, 116.033  Sold it to buy a '97 Crown Vic.  Made sense at the time.
1971 250C, 114.023
1976 280C
1970 250/8

OzBenzHead

#8
My 1979 Euro K-Jet 280SE M110 gives me, on open-road work (cruising up to 120 km/h) and drinking 98 RON, 11-12 litres per 100 km (approx. 23.5 - 25.5 mpg). If I extrapolate that to distance per tank full it comes to 800 km / 500 miles or better.  This car has 300,000 km on the clock and is serviced properly every 8,000 km / 5,000 miles. It has a dry-element air cleaner.  Although not a hoon, I am not a slow driver and tend to fang it up hills, passing all those who can't / won't maintain at least the posted speed limit. The handbook suggests about 11-12 litres / 100 km.

Around town it is quite thirsty, but as I live in a smallish rural city and walk to most of the shops (a block away from home), that's not really an issue.

OTOH, a poorly maintained 1978 280SE M110 (Oz spec), with oil-bath air cleaner, that I bought for parts returned, on the only two trips I made in it before taking it off the road, about 15 litres per 100 km (17.75 mpg).

From my 1970 W108 280SE M130 (oil bath air cleaner) I also get 11-12 litres per 100 km (approx. 23.5 - 25.5 mpg) -- though this car is less thirsty around town, probably because it has the fluid coupling rather than a slushy torque convertor. This car has almost 837,000 km on the clock.

My 1965 W111 220Sb M180 (oil bath air cleaner) is a very thirsty beastie: 15-16 litres per 100 km (17.75 - 18.8 mpg), but it does have two dual-throat Zeniths. (Approx. 233,000 km on clock.)

My 1965 W112 300SE M189 coupe (oil bath air cleaner) is also thirsty: 14-15 litres per 100 km (18.8 - 20 mpg) -- but is well within the factory-claimed range for the six-plunger-injected M189 engine of 11-18 km per 100 km. (Approx. 250,000 km on clock.)

Wherever I go, I always carry a large toolbox, gallons of spare vital fluids, and sometimes a 2.5 tonne capacity trolley jack, so a reasonable load in the boot. (Of course, I only ever need those tools and supplies when they aren't on board! Carrying them seems to prevent problems.  8) )

I have no complaints about fuel consumption. I wonder if there is usually a big difference in thirst between Euro, US, and Oz-specced versions.
[img width=340 height=138][url="http://i12.photobucket.com/albums/a215/OzBenzHead/10%20M-B%20Miscellany/OBH_LOGO-2a-1.png"]http://i12.photobucket.com/albums/a215/OzBenzHead/10%20M-B%20Miscellany/OBH_LOGO-2a-1.png[/url][/img]

Maat1985

QuoteA new MPS Maat?  Was it yours that might have been tampered with? ie adjustment screw possibly adjusted previously?  PM 13B and see if he has any left, he had a couple of spares a while back.
yes that is exactly what has happened to mine.......
QuoteBe aware that out-of-tune D-jet 280's can really chew fuel.  I know of a few that can only get 250 to 300km on a tank.  But on the other hand, when sorted, the D-jet should be more efficient than the K-jet. 
what needs to be done to tune properly???? i have changed the spark plugs recently.... it has good ignition leads and the dizzy appears to be quite new as well..... i imagine i need new air filter...... i recently have put in a few loads of injector cleaner..... so other than the MPS what should i look at????? adjustments to be made???? filters to replace???? should i take it to a mechanic to get it done properly or should i attempt it myself?????
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

Maat1985

will it be performing better if its out of tune and using more petrol or is it just being wasted????? i know it is probv performing better cus it is running rich......
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

s class

Running the car grossly rich will just waste fuel, foul the plugs, dilute the oil and lead to excessive cylinder wear.  Slightly rich will benefit performance slightly compared to slightly lean.  Getting the MPS sorted out is a big part of sorting D-jet out.  Other issues that will negatively impact your consumption (and performance) are valve clearances (significant effect) and ignition timing.  Both valve clearances and ignition timing are pretty simple to sort out.  I would check those, then get to a workshop that has an exhaust gas analyser so you know just how rich you are running.  It really would be beneficial to sort out the odo as well, so you are not working in the dark. 


[color=blue]'76 6.9 Euro[/color], [color=red]'78 6.9 AMG[/color], '80 280SE, [color=brown]'74 350SE[/color], [color=black]'82 500SEL euro full hydro, '83 500SEL euro full hydro [/color], '81 500SL

13B

Ignition timing is very critical with D-jet, because as you move the distributor you also change the timing of the trigger points, making them fire slightly earlier or later as you move the dist. back and forth.

We experimented on my 450SE V8 D-jet race car and found that it always ran the best with ignition timing set to 0 degrees TDC, wheras with other non-MB V8 race cars we found somewhere between 10 and 15 degrees advance was a sweet spot.

I.
450SEL 6.9 #5440 = V MB 690 , 450SE # 43094 = 02010 H , 190E/turbo # 31548 = AOH 68K

Maat1985

how do you check and adjust the ignition timing????

and valve clearence??????
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

13B

To answer your 2nd question first - if the cams quiet and not "clattery" then no adjustment is needed.  On a D-jet with manual adjust lifters, they can be slightly audible and thats OK.  If they are annoyingly loud - ticking - they probably need adjusting.

To adjust valves its job # 753:

And to check ignition timing its job# 782: Link

I.
450SEL 6.9 #5440 = V MB 690 , 450SE # 43094 = 02010 H , 190E/turbo # 31548 = AOH 68K