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

s class

Ian, its true that the valve clearances are probably OK, but my thinking was that since he's trying to get the car in a proper state of tune, one needs to start by checking the basics before moving on to the fuel system.  I have noticed on my 280SE, since the banning of leaded fuel here in South Africa (only about 4 years ago) that I do need to adjust the valves from time to time, due to what I can only assume is some seat recession. 


[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

Maat1985

QuoteTo 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.
well i hear no noise from the motor at all that is abnormal so i would say is all good......
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

s class

If the valve clearances are too tight, they will be very quiet, an you will notice loss of power and increase in consumption.  Valve seat recession leads to a progressive loss of valve clearance, hence the need for periodic checking. 


[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

Maat1985

also too once i replace the MPS i would think mayb it is best to get it serviced and tuned properly.... where in sydney would be a good place to do this... i imagine places like ultratune while specialising in tuning of cars prob dont have much of an idea and is prob better left for a merc specialist.... what is others opinion on this and who do you reccomend i hear merc talk in botany are really good however that is a fair way from where i am......
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

s class

Good plan.  Don't let this talk of valve clearances detract you from MPS replacement, as that is probably where your biggest problem lies.  You are correct - you need a specialist, as the average workshop servicing recent model cars will have no idea about D-jet, or probably even with solid tappets. 


[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

oscar

Maat, if you're going to seek help from workshops I can't think of anyone off the top of my head in Syd, but check the NSWMBC forum for recommended workshops or one close to you.  I'm sure there was a Sydney thread in the link below but start another if you can't find it.  You should get plenty of pointers for where to go.

http://www.mbcnsw.org.au/forum/index.php?board=9.0
1973 350SE, my first & fave

13B

Can't find the picture at the moment but on my engine you can see on the cam lobes its shiny where they touch the rocker arms, and varnish on 'backs' of the cams indicating the valves are closing properly.  This applies to manual-adjust tappets.  Hydraulic lifters as fitted to 1976-onwards V8s give cams which are shiny the whole way around.  Do any of the 6cyl cars have hydraulic lifters?

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

s class

No - all the M110's have old fashioned manual tappets. 


[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

In this picture of my D-jet 450SE engine with the cam cover off you can see the shiny lobes and varnished backs of the cams.  Its not very scientific, but if you top end doesn't make much noise and the cams all look like this (shiny lobes/varnished backs) then I'd say they are adjusted pretty much right.



On this engine you can hear the cams clatter a little when cold but they quieten down once the engine has warmed up.

This is a warm start:

Link

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

Maat1985

i'll see how it goes once i get my MPS sorted....
i ran a heap of top quality injector cleaner through at the same time i filled up ith 98 octane and now i have noticed an improvement as i have just driven 200kms this week in a mix of city and freeway driving and have used just under 1/2 a tank.... between 1/3 to 1/2 a tank but it is hard to tell exactly so i'd say atm i'm looking at between 450-550km per tank.... is hard to estimate with no odometer...
i just went onto google maps and put everywhere i have driven this week and added it up....
BTW does anyone know how much it'll cost to get my odo fixed as i'm not that confident to do the job myself...... is it the same job to fix the trip counter or is that seperate cogs etc.....
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

OzBenzHead

A few years ago I consumption- and performance-tested 95 RON and 98 RON over a 6-month period on both my M130 280SE and M110 280SE.

Both cars usually gave similar consumption figures on identical fuel. The extra cost per litre of 98 over 95 was bettered by a percent or five (I can't locate the record just now) lower consumption in km per tankful; i.e. 98 proved more economical over the tankful, performance was notably better, and the cars seemed to maintain better tune between services (especially notable being my twin-Zenith Finny with rebuilt carbs). Win-win-win (the first winner being, of course, the oil companies and government coffers).

In just about any Benz, I reckon 98 is best for car and pocket.

I'm not into additives in the dailies, but my 'ancient' Sunday drivers get Shell's version of Flashlube with each fill -- just for the extra feelgood vibes.

Once every couple of months I add 0.5% (half litre per full tank) synthetic two-stroke oil (Stihl, made, I think, by Shell). Seems to keep things really clean, makes no smoke or ash.
[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

#26
i find that few so often i am adding an injector cleaner.....
i think that if 98 is gunna give me better economy..... (less L per KM = more KM per tank = less money spent in fortnight of driving)
and a cleaner motor (better performance and a longer lasting motor)

that there is no way you can possibly lose....
i just worked out that at 220km per 1/2 tank which is roughly what i am doing atm is 21.8888888L per 100km/s which is shocking.....
i am hoping for 600km per tank which is 16L per 100km/s after changing my MPS then even more after a service and tune which will prob have to wait a while (NO $$$$$$$$$ ATM)

I just wonder how much performance i may lose after changing my MPS cus running richer to some extent will increase performance......

if i lose a decent amount i will keep the old MPS for when i wanna have fun and not worry bout petrol consumption ie. track day....

mayb i should get it dyno tested with both and see if there is a difference....

never know mayb it'll be a great performance upgrade...... if it is i'll easisly be able to switch between economy driving and performance driving... just pull over for 5 mins and change it.... lol.....
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

TJ 450

There wouldn't be much, if any difference between fixing the odometer or the trip meter, it is probably just slipping or jammed cogs.

I would say 600km per tank is overly optimistic for around town... what you are estimating now is actually what I would imagine to be about the maximum achievable.

After replacing the MPS, you can always adjust the mixture accordingly. At least you know everything is functioning properly then.

I seem to recall getting about 300km to half a tank in my 450 driving out to the WA German Car Day recently. The mixture was obviously lean at the time.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

Maat1985

when adjusting the MPS how do you tell the optimum setting????? without being able to measure the exhaust gas... ie without tools and exuipment?????
DRIVER - 1977 W116 280SEL Orange....
PARTS - 1977 W116 280SE White....
DECEASED - 1977 W116 280SE Maple Yellow....
DECEASED - 1976 W116 280SE Green....

TJ 450

Yes, you need to have an exhaust gas analyzer to adjust it to spec. Any decent workshop will have one though and it would only take a few minutes to adjust if they know where the ECU is located.

You may be able to ballpark it, but you run a few risks there if it goes wrong. I'm not sure how sensitive the adjustment is either.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500