The M117.968 560 Engine

The 560 is the ultimate M117 engine.   This family of engines was introduced in 1969 with the 3.5l M116 and was followed in 1972 with the 4.5 M117.   The M117 is a longer stroke version of the M116.   Both engines share a SOHC design, 2 valves per cylinder and always had fuel injection.

These engines evolved over time with the final iteration coming between 1985 and 1991.  The 560 was the largest M117 engine offered, although to be pedantic it is actually 5.5 litres.

M116M117Fuel InjectionOtherApplications
1969-1975: 3.51972-1975: 4.5D-Jet EFIIron BlockW108, W109, W111, W116, W107
1976-1980: 3.51976:1980: 4.5K-Jet (CIS) MFIIron BlockW116, W107
1980-1985: 3.81978-1985: 5.0K-Jet (CIS) MFIAlloy BlockW126, W107
1985-1991: 4.21985-1991: 5.0, 5.5KE-Jet (CIS-E) E-MFIAlloy Block, Bigger Valves, EZL IgnitionW126, W107, W463

The story goes that Mercedes-Benz were concerned that the introduction of the BMW E32 7 series with its 220KW V12 placed the W126 at a competitive disadvantage.    The W140 was apparently delayed to respond with a V12 and the 560 was a short term competitive response.  The 560 is a longer stroke version of the 500.   At the same time larger valves were also specified.  The 560 offers more power than the 500, although the 500 has the reputation of being the smoother engine.

To meet the E32’s specs a high output version of the 560 engine was offered with 220kW.  This engine had a raised 10:1 compression ratio, different cams, ignition timing and an improved exhaust system.  It was coupled with a 2.65:1 rear end, allowing it to outperform the E32.   The 2.65 contrasts with the 2.24 ratio used on the 500, and the 2.47 used on the 420.   At first, the high output version was an option, code 822.   It was offered from 10/1985-9/1987 and known as the ECE version.   My 1987 560SEC is the code 822/ECE version.

The ECE version was a start, but more and more markets in Europe required a catalytic converter.   Mercedes offered two versions for this case.   The KAT version had 180kW and had the Catalyst fitted as standard.  The RUF version was set up to allow the catalyst to be retrofitted later and had 200KW.   Both of these versions ran the standard 9:1 compression.

Mercedes still faced a challenge against the E32.   Many European markets required the RUF or KAT version.   Therefore, from 9/87 the RUF and KAT versions were revised.   Compression was raised to 10:1 and other changes introduced, such as knock sensors to retard the timing when necessary.    This made the ECE version redundant, as the RUF version now also had 220KW.  The RUF version could still be retrofitted with a catalyst.    The KAT version now had 205KW, a useful improvement.  While not the subject of this article, the compression ratio changes were also applied to the 420 and 500 engines, providing a useful power boost.  The 10:1 engines either have HV or E10.0 after their engine numbers.

The 560 engine also offered an opportunity to provide more performance in markets with strict emissions laws.   The larger motor still allowed good performance even when de-tuned for idle emissions.    This was particularly important in the all important US market.    The 1984-85 500SEL in US spec only managed 137kW.   The move to the 560 allowed power to be raised to 178-180kW depending on market.   My 1988 and 1989 560SECs were both this version.   One particularly restrictive element of this 560SEC is the exhaust system.   There is a crossover pipe that joins the output of both banks of cylinders into a single catalyst.     The primary destination of this 560 was the USA, but it also formed the basis of the Australian and Japanese versions, with minor changes.  This version of the 560 was equipped with a 2.47:1 rear end instead of the 2.65 used in other 560s.

Unlike the other 560 engines, the emissions version never had the compression ratio revisions.   It was the same story with the 420.  The rest of world 420 had the compression rise but the emissions version did not.

It was this emissions engine that was the only 560 available in the R107.   The 560SL was only offered in Australia, USA and Japan.   It was slightly lower in power than the W126 version as the exhaust was more restricted.     This is why it has less powerful than the contemporary 500SL.   The big advantage of the emissions engine is that it can run lower octane (91) petrol.

VersionDates AvailablePowerTorqueCompressionOther Attributes
ECE10/85-9/8722045510:1Code 822, No knock sensors, revised cam, timing
9/87-10/9122045510:1Knock sensors
KAT (US, AUS, J)Entire Series178-1803899:1

The differences between the engine types are extensive:


The high output versions had ‘tri-y’ exhaust headers.   Essentially the tri-y setup consisted of four piece manifolds that joined under the car into a dual exhaust system next to the transmission.   The mid output versions had ‘euro log’ exhaust headers which was a single manifold for each side, each with a pipe under the car to the exhaust system. When catalysts were fitted, there were two.   The final option was the restrictive system where a crossover pipe behind the engine linked the two manifolds together to enter the single catalytic converter.    The KAT/RUF cars have an oxygen sensor.

The engine photo clearly shows the exhaust manifold from the ‘tri-y’ setup.


All models used EZL based ignition, but the map was different.   The mid and high output models had a switch to allow the engine to be de-tuned for poor fuel.    The emissions controlled models were not switchable.    The high output motors have a more advanced ignition, and the later (post 9/87) cars have knock sensors.   As the early ECE versions do not, they require 98 octane fuel.


High output engines hav different camshafts with ECE, RUF and KAT camshafts all having different part numbers.

The ECE Camshafts have code 16/17 (Left/Right).   RUF are 24/25 and USA is 26/27.    The ECE and RUF cams have the same profile.


  • The strict emissions version has an air pump.
  • The high output motors also have a different fuel distributor.
  • All 10:1 compression engines have high compression pistons.
  • The high output models have a separate oil cooler and pump.   This is located at the front left of the car.
  • High output models have a different (black) transmission modulator
  • Transmissions were the same on all models.   Starting with the 722.323 and then later the 722.350.   The .350 transmission was improved over the 323.

Unlike other engines, all versions of the 560 are good.   Even the emissions versions have plenty of power and are a delight to drive.   The M117 has an almost bullet proof bottom end, but an Achilles heel in some plastic parts in the engine.  If these parts fail, it is not economically viable to fix the engine.

W111 Heater lever upgrade

Most Mercedes from the mid 50s to the late 60s had a similar set of controls for the heater.   There are four horizontal levers controlling the amount of heat and the direction of the air flow.

At least on the W111, the lever on the top left controls the amount of outside airflow.   The top right controls the direction of the airflow.   The two bottom levers control how much heat on each side is allowed in.   There is no provision for A/C as this was not integrated into the controls until the mid 70s.

The levers were originally chrome, for example in the 190SL.   Later on as the dashboard evolved the levers were changed to black plastic.   This was ostensibly for safety, but there was probably a little cost cutting involved too.   The same reason was given for other changes in the dashboard, such as the removal of the wooden instrument binnacle.

W111 Heater lever

Over time the plastic levers become a bit beaten up looking.   They also don’t really fit the look of the dashboard.   As the levers simply slide into their receptacles, they can be easily replaced.   I normally like to keep cars original but mods that are easily reversible make sense.   The picture above shows the levers on the right replaced and the original plastic ones on the left.

Much worse than the levers is the horrible 90s radio.   This will be a project for another time.   Unfortunately the dash opening has been enlarged for a DIN radio.   This means the original radio will no longer fit.   I will probably adapt one of the retro radios with a 70s faceplate.

The W111 heater lever look much better in Chrome than they do in black plastic.   This upgrade would also make sense on other cars like the W108.   I’ve saved the plastic levers in case I want to put it back to stock.

W111 Heater lever


DS Front End Repairs

A couple of months ago my DS had one of the front suspension boots replaced to cure a bad LHM leak.    When this was done, it was apparent the bushings in the steering rack were worn.  Since the front of the car was apart, it made sense to order these parts and then have them fitted before the front was put back together.   I ordered the parts a few months ago, but for some reason Franzose sent them by the slow boat.   This was rather irritating as the DS has been sitting partially assembled for months.   Some of these repairs are beyond my skill so are being entrusted to Jason who does all the non routine stuff on my DS.

The car also had a vibration from the camshaft pulley.  This was a good opportunity to replace it with a rebuilt one I had purchased.  The one on the car had been welded up and it vibrated.   Due to its configuration, the DS uses a camshaft pulley for accessory drive.   Most cars use a crankshaft pulley.

Steering rack bushings

The aerodynamic shape of the DS precludes a normal radiator grill.   Instead of air being forced through the radiator once the car is up to speed, the DS engine fan sucks the air up a chute through the radiator.   At idle, the fan is not running very fast, so in traffic the air flow over the radiator can be sub optimal.    This is why the fuel injected models and the DS23 have an auxiliary electric fan.   The electric fan cannot replace the engine fan in the DS, as it will not pull enough air at high RPM.   It can supplement it in heavy traffic, especially in a hot climate like Australia.

I purchased a slimline Davies Craig 10″ fan.  The airflow rating is just under 700CFM and draws 7 amps. It was mounted behind the radiator.    This is where the factory mounted the electric fan and doesn’t stop air hitting the front of the radiator.  We also added a fan controller so I can adjust the cut in temperature.   This can be seen to the left of the radiator in the picture above.   Also visible in the picture without the radiator ducting is the ducting for the front inboard brakes.

There are a number of finisher panels under the front wings around the wheels.   These had surface rust, so were powder coated along with the air cleaner assembly.   They look much better, especially with the new paint job.

Powder coated panelsAfter all these repairs the front of the car is back together and the wings on.   I have some of the original stickers to mount on the new powder coated air cleaner once I give it a clean.

Back together

Before Jason came to work on the car I had given the radiator a good flush.   Being originally from South Australia, the cooling system on this car was quite dirty when I got it.   This time, a few years later I was able to remove some more deposits but it was much better than before.

The car is not yet finished.   I was unable to adjust the windows properly.   Turns out the mechanisms have been modified in the past with non DS parts.    This will be fixed along with wiring up the new fan.  The new powder coated pieces look great compared to how it was before.

Powder Coated

I’m looking forward to driving the car again. It has been off the road for a while but is going to be much better with these repairs.

Auto Brunch St. Ives February 2019

Auto Brunch event is a cars and coffee event held monthly at St. Ives Showground.  I attended back in November and enjoyed the day.    It’s an easy event, you can drive in and be parked in minutes and leave whenever you like.   With over 100 cars on display its a nice way to spend an hour or so.

This time I took two of my young children who also enjoyed looking at the cars.   We only stayed about 30-40 minutes which was enough to have a wander around and check out the display.

As we had another event on later in the day, I didn’t have time to go and get one of the other cars.   I took the 300SE which was filthy from the light rain earlier in the week.

It was the start of a hot summer day in Sydney so there were a number of open topped cars out, including quite a few MGBs.   As usual there was a good mix of different interesting cars.    Unlike some of the other events with over the top security and lots of rules, I love the informality of this event.    I would encourage anyone to drop in to Auto Brunch on the first Sunday of the month as St. Ives Showground.

560SEC fuel leak

When I last used my 560SEC before Xmas, I noticed a rather large puddle of petrol underneath it.   I’ve not driven the car since as it is rather dangerous to drive with such a leak.   I had assumed it was probably fuel hoses.  Many cars run on E10 rot their hoses.  I purchased a few of the relevant hoses so I would only have to do the job once.  In addition, I had previously acquired a filter for the car and keep a spare K-jet fuel pump just in case.

Here in Sydney it has been mostly mid 30s C and 80% humidity for the last two weeks, so I have not been particularly motivated to work on the car.   We finally got a break in that weather so I went down and had a look.

On removing the cover, I found the main leak coming from one of the two fuel pumps.   I also found the fuel hose from the filter to the hard line that supplies the engine had been poorly modified for the wrong fuel filter.  It didn’t look like it was in great condition either.

560SEC fuel leakThe picture above shows the replaced pump (the one furthest from the camera) and the replaced filter (above the front pump).   The hose in the foreground is the one that looked bad, it had been cut and a different hose spliced in to attach to a different type of fuel filter.     A pump and filter change on these cars is simple, but a little fiddly.    Unlike the 300SE, the fuel that came out of the filter was not dirty.

While I was able to get the pump and filter changed readily, I was not able to disconnect the fuel hose from the hard line.   The hard line is up behind the differential and drive shaft, and my 17 and 14mm spanners were too large to get up there.   I tried for a while, but not wanting to break the hard line, I decided to give up and have somebody else look at this.   Luckily there is a European mechanic 20m away from my little workshop.   I’ve never used them before, but this is a good opportunity to push the car down and see if they can get this sorted out for me.   They seem to mostly cater to BMWs, but I’ve seen a 560SL there before.    With the pump, filter and this hose changed, it should cure my 560SEC fuel leak.

In the future, I wouldn’t mind changing the hose from the tank to the fuel pumps, as it looks a bit older.   I don’t have one of these hoses to hand and the tank would need to be drained, so better to wait until its mostly empty.

Before I started this job, I noticed another issue.   I had pushed the car back into place because of its leaking fuel pump and not moved it for a few weeks.   Pushing it back out I noticed a massive pool of ATF on the ground.

560SEC ATF leak

Strangely enough, while I was using the car daily, I hadn’t seen a leak.   The car did come to me quite low on fluid. There is obviously a leak that seems more based on time than use.  Looking under the car, it seems to be on the plastic attachment with the two lines coming out of it.   Possibly there is some kind of O-ring that has broken there?

ATF leak



Hero Hoists Side by Side Parker Installation Part 4

The Hero Hoists Side by Side Parker is now installed and fully operational.   The locking mechanism is now working, and I have put the E-Type on top.   In the last part, I had the electrical connection hooked up and did the final adjustment.

Hero Hoists Side by Side Parker

The challenge I had with the locking mechanism was that a 1M rod needed to be installed from the rear of the hoist.   I did not have this much clearance.   To solve the issue, I cut the T-piece off the rod with an angle grinder and drilled out the bit of rod left in the hole.    I then purchased an M12x1.75 threaded rod from Bunnings warehouse and was able to get that rod into the hoist from the underside.   I then used nuts and washers to affix the T-piece back on the threaded rod.


This worked fairly well and the locks are now functioning as they should.   This hoist has two sets of locks and they look quite robust.

Threaded Rod

I also wanted to make a minor adjustment to the placement of the hoist.   This is no problem as it comes with a castor kit.  It was a pretty simple matter to install it and move the hoist about 200mm.   I was able to do this on my own.

Hero Hoists Side by Side Parker Castor Kit

The hoist is a tight fit for me, but worth it to get two more cars into my warehouse.   As outlined in the last part, I need to investigate adjusting the drop ceiling to gain an extra 100-120mm.   This will provide more flexibility for the upper cars.    Unfortunately this is probably not going to be enough height to use the 9th lock position.   Using the 9th would have allowed the Traction to be stored underneath.   The final configuration will probably be E-Type and SLC on top and DS/560SEC down below.

In the future, I may investigate an LED kit for the underside of the ramps.   I may also look at getting some wooden inserts to fully protect from drips.   Hero Hoists offer an aluminum insert kit, but its quite pricy.  It also covers the middle of the hoist between the ramps.   This wouldn’t apply in my case as I have shifted the second set of ramps to the right.

Hero Hoists Side by Side Parker Installation Part 3

The Hoist is almost operational!  The only thing left is to get the unlocking mechanism working.   In part two I installed the motor and hydraulic lines.   Yesterday an electrician connected up the hoist for me.   After fixing a minor hydraulic leak I had a working hoist (sans unlock rod).  This is timely as I needed to get the 560SEC inside.

While the unlock rod is not working I can manually unlock the hoist if I need to.   I was able to position the hoist at the height setting I’ll likely be using it and park the 250SE underneath.


The hoist is a three phase 415v model.  It was no extra charge and since I have three phase power I might as well use it.   The motor should be more efficient and last longer.

Today I did final checks and looked to balance the hoist.   It was odd because one corner was about 10cm off the rest which seemed strange.  On closer inspection I found that the cable had come off its runner.   This probably happened when I first applied power to the motor.


As can be seen in the picture, there are rods to stop this from happening.  Fixing the problem is pretty easy – put the hoist on its locks to take tension off the cable, disconnect it from the post and remove that rod.   It is now easy to re-route the cable and re-install the rod.

Once I had positioned the hoist I was able to measure how much space I would have at various positions.   At the most likely one I will have 1344mm above and 1559 below.  This should allow me to have the E-Type and 450SLC on top and most cars (Traction excepted) below.   I do have the possibility of raising the false ceiling about 120mm to give a bit more room up top which I will investigate in due course.   The 250SE is there now, but as it is the widest car I own, it will not usually park under the hoist.

Concluded in part 4.

Product Review Update: SCA Hydraulic Vehicle Positioning Jack

Back in 2015 I did a review on the SuperCheap Auto Vehicle Positioning Jack.  I had purchased a set of these during a SCA sale.     Overall, I have mixed feelings about this purchase.    The jacks are useful to move cars that are not running.   The big challenge with them is that moving even a medium sized car requires two people, even on a flat concrete floor.   It is much easier to push a car without the jacks if it is moving in a straight line.

My expectation was that I would be able to push a regular size car around myself.  I expected that it would require effort, but I did expect to be able to do it.    The only car I have moved on the jacks that was easy to move had no engine.   Moving a race car with no interior, but with a motor was nigh on impossible on my own.

Vehicle Positioning Jack

It would also be easier to use them if they would open about 5 CM more.   As can be seen in the picture, one of the plastic guides has split, but that is my fault for moving part of the hoist on the jack.

Surprisingly, if the need is to spin a car around, it can be easier to use only two of the jacks instead of all four.

I do not know if the inability to move a car is due to this particular vehicle positioning jack, or is common to all.   I suspect this is a cheap unit and others are better.

Hero Hoists Side by Side Parker Installation Part 2

In Part 1, I had done the heavy lifting to get the Side by Side Parker installed.    I have arranged an electrician to come and hook the hoist up on Wednesday.  This gave me a deadline to get as much as I could before they arrive.   Most importantly to mount the motor.

The motor is quite heavy, but straightforward to get mounted.   A hydraulic fitting needs to be screwed into the motor so it can drive the hoists hydraulic cylinder.   The hydraulic fluid chamber also must be filled.   The motor can be mounted either at the front or back of the post.   Even though it may be slightly more awkward to operate, mounting it at the back will save space.

Side by Side Parker Motor

Next was to install the mechanism to release the locks.   This involves a serious of rods that are controlled by a handle near the power unit.   This was proceeding quite well when I noticed a problem.   To fit the rods to connect the rear lock release, a rod must be inserted that is about a meter long.   I don’t have a meter of clearance at the back of the hoist.   Due to the posts in the workshop, I don’t have that much space to move it forward to add in this rod.

I may need to find a way of cutting this rod so it can be inserted from underneath.  If I cut it, I will need to find a way of re-joining it, so perhaps having threads added?   The picture below shows the rod on the right with the T-piece at the end.   This T-piece means I cannot install it from the bottom.    This is the only thing I have left to do before the core installation is done.

Locking Rod

I may not be able to solve this by Christmas.   At least having the power connected should allow me to raise it to the highest level so I can park cars underneath until I can find an alternate to this rod.

Continued in Part 3.

Hero Hoists Side by Side Parker Installation Part 1

I help defray the costs of my workshop by renting some spaces for car storage.   This was making the workshop quite cramped, especially with the addition of the 560SEC.  Hero hoists offered an interesting four post hoist – a model that could lift two cars side by side and lift them both without the centre pillar.     The presence of the centre pillar would have made it difficult to get some other spots to the left of where the hoist is to go.

The idea was to be able to take a 4th car for storage and still have room for my cars plus a workspace.   Hero Hoists offer two models of the side by side parker.   the regular one and the high lift model.    The high lift model is probably the better value, but its a bit deeper too and I couldn’t fit the extra depth nor need the higher lifting capacity.    Personally, I would have found it better if the smaller model was narrower by 200-500mm.

I found Hero Hoists to be pretty easy to deal with during the buying process.   I was able to come out and look at a similar model on the weekend and they were able to answer all my questions.   The price is reasonable for what you get.    One slight downside was that the shipping took a lot longer than anticipated.   Obviously this is not completely in their control but worth noting.

Hero Hoists are not a manufacturer.   They have an OEM relationship with Advantage Lifts (in the USA) who have the hoists manufactured.    Therefore there is a lot of information about the Advantage lifts that can be found on the internet.   I was quite impressed with the inclusions including caster kit, jack trays, drip trays etc.   The hoists also appeared to be well constructed and sturdy.     These lifts do not require compressed air to free the locks, which I see as a big advantage.

Based on the videos that explain how to assemble the lift, I figured that my Brother and I could do it.   Professional installation is quite expensive and you still need an electrician to connect it.    The delayed shipping meant the hoist only arrived the day before he was moving to Perth so I only had him for a few hours.

The hoist arrived on a tilt tray and realistically you would need access to a portable forklift or an engine stand to remove it.   I was very lucky in that the time the hoist arrived my neighbour at the workshop (who has a forklift) was around.  He was able to help unload the hoist from the truck.

Hero Hoists

The hoist is seriously heavy – the delivery package weighs more than 1.5 tonnes.   Unfortunately, the forklift is too tall to fit into my workshop.   We were able to use it to get the hoist close to the door.    If you didn’t have the forklift you would need to use an engine stand and remove one piece at a time.

Hero Hoists DeliveryThe hoist is extremely well packed.   The pieces are bolted together and there is plenty of cardboard and bubble wrap.   From here, a portable hoist would be highly reconnected.   This lift is heavy duty and very heavy.

The two heaviest pieces are the cross beams.   To get them into the warehouse,  we lifted up one end at a time and inserted some wood blocks under each end.   This gave enough clearance to lift the cross beams up with the forklift and lower them down onto my car dollies.   The car dollies made it easy to wheel them inside.

Next are the ramps.   The power ramp has a hydraulic cylinder inside and is extremely heavy.   We needed to borrow some neighbours to lift it off.   Even with four men it is quite heavy.   We were then able to lower it onto a car that raises hydraulically about a meter.   We used the cart to bring in all four ramps, with the power ramp last so it was still on the cart.

The posts are comparatively light.   They can be moved by one person at a pinch but with two its very easy.    Using the cross beam on the dollies, were were able to position them roughly where they should be.   We were then able to push the cross beams onto their side and insert the posts from the bottom.   As our cart moves up a meter, we used the lowest lock to position the cross beam.  Once the cross beam has both posts inserted, it is a relatively simple operation to stand it up.

To position the power ramp, we used the cart to raise it higher than the cross beams.   We could then position it and gently lower it down onto the cross beams.

Hero Hoist assembly

At that point my brother needed to leave but the heavy work was mostly done.   I was able to manoeuvre the ramps onto the cart and use the cart to position them where they needed to go.   A floor jack was helpful to bring the last ramp up from floor level to make the lift onto the cart easier.

Moving the ramps around

Minor adjustments are possible once the ramps are in place.   Next step is the control cables.  I found the videos to be far more useful than the manual which is for the generic four poster.   One item that is not covered in the videos is the extending of the hydraulic cylinder.  This is mentioned in the manual.   If this is not extended then there is not enough length to connect the control cables to the top of the posts.

Each post has a top cap that allows the cables to be installed.   The cable routing is quite easy once you have watched that section of the video a couple of times.

Hero Hoists installation Next step is installing the locking actuators and the motor assembly.    I have an electrician coming later in the week to hook up the power.

Continued in part 2.