6.9 - Changing engine oil

More threads by Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
If one keeps it simple, the job is straight forward - well, at least, you would think so. Two ways of doing it - depending on facilities at your disposal, and the amount of care you want to put into it. I'll go the simple way first, assuming you don't have a lifting hoist - in other words, you're doing the job "on the ground" so to speak, with the help of a good quality trolley jack.

1) Set the sliding disk on top of the distribution valve to the high setting, start the engine to attain the high level. Turn off engine.

2) Slide trolley jack under engine and jacking point member, and lift high enough to "just touch" that member. DO NOT LIFT THE CAR AT THIS STAGE.

3) Move the sliding disk back to the "lock" position, and now further lift the car until you are able to slide 6" by 6" timber blocks under each front wheel, lower the car (obviously with wheels attached) down unto the timber blocks - at this stage, you should be able to observe if the "locked" position will hold the car in the locked position. If not, there may be some problems a little down the track when you come to lower the car back to the "road position" after completion of the oil change. Withdraw the trolley jack from under the car.

You now have unimpeded access to the drain plug, plus the car is high enough to comfortable slide under a large container to catch all that oil that will come gushing out once you remove the drain plug. A word of warning: If you are draining hot engine oil (and it should be HOT to get a clean and proper drain), be careful not to get scalds on your hands. Also a word of advice - it pays to remove the capped dipstick from the reservoir top to eliminate possible air locks.

So now, you will need a 14mm Allen headed socket to remove the drain plug - but as I said, be careful. I normally leave the oil to drain for about two hours. During that time, I take the opportunity to remove the oil filter housing and oil filter. Again, have a reasonably sized container to place under the housing. Also, as you are loosening the long retaining fixture bolt, there will be quite a bit of oil "splashing", so have a rag handy to clean your hands. Also, the housing and filter are quite heavy and you are likely to drop the whole assembly, preferably into your container.

Also, in the two hour period, I wash the filter housing in kerosene, and degreaser, and wash out with water, but make sure to blow it dry with compressed air. Once you have fitted the new filter to the canister, refit by means of a 17mm socket and short extension. Now, you should be ready to tackle the task of refilling with fresh oil. Invariably, I start off with about six liters of "very good quality" oil, start the engine and observe the oil pressure gauge to rise to the "maximum" position. Switch off engine, and add the extra six liters (the system hold a total of twelve litres), restart engine, and keep running, and then proceed to stick your head under the front of the car to make sure that there is no oil leakage.

Last step is to place two blocks of timber (3 by 4) BEHIND the 6 by 6 timber blocks and drive the car off BACKWARDS, lift bonnet and return the control disc back to the "NORMAL" position - resting against the rolling pin. You should now be in business, as long as the car's suspension will co-operate with you. Most of the time it will, sometimes it won't and that's when your fun can start. Regards Styria

N.B. Next post will deal with some procedures that I like to follow. If anyone has any queries, just communicate within the guidelines of this thread.
 
Last edited:
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
Having outlined the 'basics' of changing engine oil in 6.9s, I would like to demonstrate some further procedures that I follow, and these have been sourced by various problems I had with Gleaming Beauty at the time when I was forced to remove heads and carry out extensive engine work caused by a leaking head gasket and the mixing of engine oil and coolant.

Whilst I went to considerable lengths at the time of carrying out that work to eliminate all 'old' and sticky sludge, it took two or three oil changes at fairly short intervals to come up with an oil texture that was to meet my satisfaction. One area of concern and continual improvement related to the sludge that had accumulated, and kept accumulating, in the engine oil reservoir. The drain plug of that container is hollow (or recessed) and it would always be full with old sludge. In fact, the very first time when I removed that plug completely, there was no evidence of oil being drained - it took considerable poking with a screwdriver to open up the hard carbon to get the oil to flow.

As a consequence, when draining engine oil as described in the previous post, I always also drain the oil reservoir, and also fill it with about two litres of Kerosene, and use compressed air to clean the reservoir and blow all kerosene into the small engine sump. At that point of time, the sump bolt is in place, thus retaining the kerosene in the sump. I then remove the sump plug, draining all kero and then use compressed air to clean the inside of the small sump.

I know this is a bit of 'overkill', but I really think that it is of considerable benefit to keep the engine in good working condition by adopting the procedure outlined. Regards Styria

N.B. Just as a matter of general observation, there are a number of 6.9s floating around in various areas, and it is a great pity that virtually no one ever writes about any work that they may be carrying out from time to time. It would greatly help to make TK more interesting. :eek:
 
Last edited:

SEL_69L

Aristocrat
Messages
1,320
Points
95
Location
Sydney, NSW, Australia
A few questions:
Would it be OK to use flushing oil to clean out a 'sludged' engine? Can the engine be started using this oil?

What is the benefit of starting the engine with only 6 litres of oil?

Why is it OK to start the engine with only 6 litres of oil? Is that small amount enough to fully lubricate the engine?
 

Oversize

Grand Master
Messages
5,753
Points
596
Location
Melbourne
If you have a trolley jack, you'll probably have a full set of stands. I'd recommend putting the whole car on stands as it's then level and will drain properly. On a 6.9 just drive it onto a couple of 6x4 timber lengths so you can get the jack under without wrecking the spoiler. Be sure to put the timber under ALL four tyres when it's lowered to the ground so you can remove the jack at both ends. Then just start the car (hopefully it'll rise up) and drive off.

I always drain the tank, sump and also remove the filter all at the same time. I sometimes let it drain overnight to be sure all the old oil is removed.

Plugs temporarily re-installed, a couple of litres of kero is a good idea before re-draining for at least a few hours.

I never install a filter dry, so add at least some oil to the filter directly before re-installing. Yes it's not easy to do on these without spilling new oil! This avoids cranking with no oil until the pump fills the filter up.... :eek:

I normally fill with about 8-10 litres before starting and warming up to check the level. Remember oil does expand, so there is a big difference between hot and cold levels! Check it hot...
 

Oversize

Grand Master
Messages
5,753
Points
596
Location
Melbourne
If you're really worried about spinning an engine with no oil after a change then remove the igniter wire and spin over until you get pressure on the gauge. Hopefully your battery is good...

If you're insanely thorough you'll remove the plugs and rocker arms to get the pressure up quickly and safely!! ;):rolleyes::D
 
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
A few questions:
Would it be OK to use flushing oil to clean out a 'sludged' engine? Can the engine be started using this oil?

What is the benefit of starting the engine with only 6 litres of oil?

Why is it OK to start the engine with only 6 litres of oil? Is that small amount enough to fully lubricate the engine?
--------------------------------------------------------------------------------------

David, I have never wanted to use an engine oil flush, especially with an engine that has hydraulically operated valves. If you ask me why I don't, I can't give you an answer. For whatever reason, I always worry about oil passages getting clogged up with sludge.

You can initially fill with six, or even eight litres, as long as it is not the full 12. Were you to use the last named amount, you will overfill the oil reservoir. Starting engine with six litres should not create any problems regarding oil starvation. I closely monitor the gauge, and it only takes about five seconds to attain full pressure. It is then that I immediately switch off the engine and add the extra six litres, and then start engine again and let it run for about a minute or two. Regards Styria
 
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
Mark, rocker arms ? Plugs - yes, not a bad idea as it gives one a chance to clean them. On the other hand, however, removing plugs allows the engine to spin quite fast on the starter motor. Would that not be counter productive, seeing that you are cranking an engine without full oil lubrication ? In any case, as explained to SEL69L, it takes but about five seconds for the oil pressure gauge to register "FULL".

I do agree with you that some oil should be added to a dry filter, but honestly I sometimes forget to do it. No excuse. Regarding you suggestion to use engine stands, both front and also at the rear - I am not so sure about that. You see, if you have a problem with a suspension set-up NOT LOCKING (for whatever reason, and it DOES happen), when you then come to lift the car, whether front and/or rear, and you lower the car, even your timber planks under the wheels of the car are not likely to enable you to withdraw the trolley jack. The car will be too low. Using the 6 by 6 under the front wheels, if you lower the car and it collapses, you still have lots of clearance to work with the trolley jack.

I also tend to think that if you have two litres of Kero in the small sump, that should be sufficient to clean all sludge when draining that Kero from the sump, and you then use compressed air blowing into the small sump opening, thereby expelling any sort of slush or rubbish that may still be sitting in the bottom of the sump. Regards Styria - BTW, nice to get your input.
 

Michel

The Prince of Arabia
Moderator
Messages
10,022
Points
775
Location
Sydney, Australia
Very interesting Godfather.

We could do a how to with pics at my workshop on the hoist, should you wish?
 

6.9forever

Noble
Messages
267
Points
125
Location
Sunshine Coast
Photos of each referenced area would be an enormous help for the uninitiated (that's me) to understand.

Thanks all, especially Styria, for the help so far.
 
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
David, I will get this organized for you. In fact, it's a great idea because I can then skite about the cleanliness of the engine and other various components. Please give me a few days to organize it. Regards Styria
 

6.9forever

Noble
Messages
267
Points
125
Location
Sunshine Coast
Thanks Styria, this will be a huge help.
 
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
Okay, I have now had the opportunity to take some pics. to illustrate my oil changing procedure. With this first photo, note the height of the front suspension - already on the high setting.

MechanicalWork042_zpsdebe2dc9.jpg

Trolley jack to be rolled into position under lifting member - remember. at this stage have the jacking point only just touching that member - you must move the control disc (as in the next illustration) into the lock position. If you weren't to take that precaution, your car will just collapse when you remove the trolley jack.

MechanicalWork047_zps42f2bddb.jpg

Control Disc in the 'HIGH' position. You need to ascertain the position if for no reason other than getting the car as high as possible to slide jack under etc. However, once the jack is under supporting (just touching !) member, move the disc back to the position as already illustrated.

--------------------------------------------------------------------------------------
In the next photo, note position of the timber blocks - at this stage the wheels are not touching, thus if you want to be industrious, now is the time to clean those rims because the wheel can be rotated freely. The secong piece of timber is there for no other reason that to just reverse the car back off the large block - that way, you're not going to damage any part of the car.

MechanicalWork048_zpsff6c9b91.jpg

The same applies to the other side. Disregard the oil stains on the concrete - I collected those BEFORE eliminating the oil leak referred to in another thread.

MechanicalWork049_zps9b44f91d.jpg

Just to digress - note cleanliness of one of the front rims - after a period of seven years since purchased and fitted to GB.

MechanicalWork053_zps641180e0.jpg

This is the drain plug for the engine oil reservoir. 17mm hex socket, with mid length extension and ratchet. That plug is hollowed out, and it usually contains hard caked sludge.

MechanicalWork051_zps386cf87f.jpg

This is a picture of the drain plug that requires a 14mm Allen key (socket) to drain the 12 litres of oil. Keep your hands and fingers off that hot oil. Leave about two hours minimum to get rid of all the oil that keeps draining into the little sump.

New battery fitted just about three days ago. Have had trouble free performance from the Delkor brand - three years warranty, and it's got a nice looking label on its side. That's very important (in case you didn't know !:))

MechanicalWork044_zps82cd2c93.jpg

Please note general cleanliness of the underside of engine and suspension - does not make the car go any better, but it makes me feel good.

MechanicalWork055_zps4c9c879c.jpg

It is hoped that the foregoing illustrations will assist the home mechanic to carry out this work. Regards Styria

N.B. My apologies - there are a couple of pics that Photobucket just seems to refuse to download. In particular, I am talking about the pic. that depicts the 14mm drain plug portruding from the little sump.
 
Last edited:

6.9forever

Noble
Messages
267
Points
125
Location
Sunshine Coast
Thank you Michael. If you could somehow post the missing photos or please email them ... I am unclear of the respective roles of the 17 and 14mm plugs and the location of the 14mm.

Was there never a workshop manual procedure?
 
OP
Styria

Styria

The Godfather
Moderator
Messages
9,382
Points
492
Location
Sydney
Mark (Oversize), I am glad that you have brought up the previous link. It sort of rounds off or completes the procedure in one fell swoop, especially as far as procuration of filters is concerned. That situation has not improved, but I have something in the melting pot at the moment. BTW, the picture of the filter being advertised on ebay - can't see how that filter could work.

Locally, the supply seems to have dried up. I have scored blanks with Ryco (not that I have ever really liked them), and also another brand, Indonesian made, but it also draws a zero.
--------------------------------------------------------------------------------------

David (6.9 forever), I will have another attempt to get Photobucket to work. Basically however, the 17mm hex refers to the filter bolt, as well as the drain plug that's attached to the reservoir located inside the front guard. Both of those hex bolts are shown on illustrations already withinn the thread. The 14mm Allen headed drain plug is attached to the right hand side of the small sump - it is the unit that has the three huge oil hoses connected to it. Regards Styria

N.B.MechanicalWork052_zps3da4f6aa.jpg

That should now do what you wanted to see.

MechanicalWork050_zps87a416f5.jpg

Success at last. Regards Styria
 
Last edited:

6.9forever

Noble
Messages
267
Points
125
Location
Sunshine Coast
Got it! Thanks Michael.
 
Similar threads
Thread starter Title Forum Replies Date
Styria Changing Differential oil Technical Information 3
Michel Colour changing car paint - Not what you think Websites and Links 4
Styria Changing Fuel Filter on 116/107 Mechanicals 15
B Oil Changing Mechanicals 19
Styria Changing Brake Fluid Mechanicals 31
c107 [JT] The Rover IOE Engine Rover P4, P5 And P6 7
motec 6.9 W116 with M156 engine Mercedes W116 12
c107 Rover P6 3500S engine swap Rover P4, P5 And P6 16
SEL_69L What do yo think is the best Mercedes engine ever? AS the tr Talking Torque 8
Styria Rover P5 IOE engine rebuild Rover P4, P5 And P6 10
S Same Engine Articles 14
Oversize 6.9 Engine Mods by MKB Mercedes W116 5
Styria Bentley V12 Engine Assembly Websites and Links 2
Patrick_R New M139 4 Cylinder Engine Mechanicals 0
6.9forever Engine swap-M102 in W123 230E Mercedes W123 3
Sluggish W116 280s engine options Articles 6
6.9forever M117 - Engine shake at idle Mechanicals 6
Oversize Engine oil type and viscosity Technical Information 6
S New VW Engine Mechanicals 11
T 280 SL (107) slight engine miss Mercedes R/C107 2
Andrew280SEL Engine Ideas for a W114 Mercedes W114 and W115 15
Oversize MB 350 V8 Engine FS Gumtree/eBay/Facebook Listings 0
Oversize 6.3 and engine/trans for sale Gumtree/eBay/Facebook Listings 5
Styria 6.3 engine mounts Gumtree/eBay/Facebook Listings 0
A engine weight Technical Information 1
A engine refurbishment Mercedes W116 3
P Poor starting hot engine Technical Information 9
260ebenz Engine bay photos Exteriors and Body Repairs 17
motec 6.9 Ford wins engine of the year Talking Torque 2
Styria Building an engine Technical Information 6
Styria Engine oil leaks Mechanicals 5
260ebenz AMG engine videos Websites and Links 8
Styria M189 (300 engine) Parts Gumtree/eBay/Facebook Listings 0
T Need a M110 engine! Mechanicals 21
260ebenz S320 W140 for sale- clean the engine Gumtree/eBay/Facebook Listings 2
260ebenz Engine just needs a tidy up Gumtree/eBay/Facebook Listings 9
motec 6.9 AMG M119 6.0 engine Gumtree/eBay/Facebook Listings 0
motec 6.9 M-100 on engine stand Mechanicals 1
S Engine swap Mechanicals 7
4 Engine Gearbox transplant on 450sEL Mercedes W116 21
Oversize AMG engine assembly Websites and Links 1
SELfor50 2 x M100 6.9 VRS Kits (1 total Engine Kit) + 2 1/4" Straight Back Exhaust Gumtree/eBay/Facebook Listings 1
L Turning the Engine Mechanicals 15
Oversize W116 engine sump guards Mercedes W116 3
Styria Detailing your engine bay Technical Information 21
motec 6.9 Engine for Michel Motorsports 3
Styria 6.3 engine in 280SL Pagoda Mercedes W198, W121 SL and W113 3
WGB M-B Publication - W116 with M117 engine Technical Information 5
Styria Mercedes Chassis & Engine numbers Websites and Links 0
Oversize Weight of a 6.9 engine & trans Mechanicals 26

Similar threads

Top