New Radio

The above Clarion radio was installed. No doubt a good model in its days with digital tuner and auto-reverse, but it sounded about as old as it looks.
Originally the car would have come with the Becker Mexico, so as the Clarion was after market anyway, I might as well put one in that has the modern stuff.
The Sony I picked does not look too modern, while it does have Phone Bluetooth and an USB connection on the front screen.
Also the front can be removed, so when the SL is parked without top, there is less resistant for young criminals to help themselves. The sound is very nice indeed, although limited with the two 4 inch dash speakers.
I will in due course install some 6.5" or 6x9 in/on the rear side panels. I've seen another SL with a speaker pod spacer so the limited depth is no issue. Anyway, that will be a fun job after a couple of more greasy ones...

Fuel system March 2012

When inspecting the fuel filter it looked like it had not been replaced for a while. The hoses also had cracks in them so looked ready for renewal. When I pulled an injector, I found that also quite dirty and although these can be ultrasonically cleaned it seemed time for a full fuel system overhaul.

The parts of the fuel system under the right rear of the car;

Start of the job; Use flexible line clamps to (1) close the hose that drops from the tank to the damper and (2) the hose between the damper and the IN size of the fuel pump.

Then remove damper by removing the hose clamps from tank, to pump and from accumulator.

With the damper connect a hose to the one from the tank and drain the remaining fuel from the tank.

Although there is a hole in the floor under the tank where not only the fuel hose drops though, but also the in-tank filter could be removed from, I found this too difficult to reach. Instead i decided to remove the tank as I wanted to inspect this anyway. 

To remove the tank, just remove the trunk rear panel. Then undo the two screws from the soft top compartment that hold the expansion tank and remove the top hose. Then undo the four bolts holding the tank down, remove the fuel out and return hose and wiggle the tank out.

On the left photo you see where the return hose is connected to. Don't forget to remove that hose. It took me 10 minutes to figure out... 

These are all the old parts that I replaced.
The old in tank fuel filter at the top and the new one underneath. It needs a 46mm socket to remove as a multi-grip pliers only slip off and damages your hand :(

On the right you see the new in-tank filter with the drop hose coming down as well as the new hose from the accumulator.
Left you see the same hoses but from the rear middle fo the car.

I cleaned and resprayed the damper and also reused the accumulator. But all the rubber between the tank and the hard fuel line has been replaced.





On to the engine side of the fuel system. Replaced the injectors its seals and insulators. Perhaps the old ones could have been checked and cleaned, but decided to do the job once and properly so just replaced all 8 with new Bosch ones (the 4 shiny copper things sticking out of the engine just above the valve cover).

These are some of the old ones with the seals and insulators.

While I was at it I also replaced the valve cover gaskets on both sides (photo of one of them here), as they were dried out and leaked oil all over the block and (on LH side) on the exhaust causing smoke.

Picture taken from the parts manual showing all the parts involved.

All in all a good days work, but the car is running beautifully smooth now, the fuel pump noise is no longer noticeable and I have piece of mind that the fuel system is not going to fail on me the next 10 years. Oh and I had much fun doing it and learned a lot.

Tires & Alignment February 2012

Now the suspension and the steering rods all were replaced, it was time for some new tires and off course the much needed alignment. There was a mix of 3 different brands of tires around the car. Although they were not all worn, I decided to replace them all with Pirelli P7 tires. I also replaced the spare, as the tire code indicated that it was from before 1980 so although never used, very much dried out.

The wheels that are fitted to the car are Zender Turbo 8Jx16H2. I'm not sure if they were a factory option or an after market, but they suit the car very well I think. The standard rim is a 14" so with these 16" the tire size differs from the book. I had the Pirelli P7 tires in 225/50R16 fitted. North Terrace Tires recommended these after my requirements if Soft, Gripping and Quiet while mileage is not so important as I'll do only 5000km a year or so.

I really like the look and feel of the tire so it was a good choice I believe.

Alignment; I tried to do an caster, camber and toe-in alignment with the eye, when fitting the suspension components, but as the car was on the hoist hanging in the air, it is impossible to get this right.
When North Terrace Tires did the alignment, I asked for a printout before and after. It turned into a horror story ;)
Camber left from +0°13' to +0°14'
Camber right from -0°37' to +0°01'

Toe left from +3°07' to +0°11'
Toe right from +0°05' to +0°11'

Setback/Caster from -0°56' to -0°29'

Geometry driving axis from -0°04' to -0°01'

All in all a massive improvement in just under 30 minutes. When I have redone the rear-suspension I'll probably get another full alignment done.

Driving out of the workshop, it's completely a different car. It was very nervous and the tracking was horrible. Now I can drive without hands ;)

Of course this had to be celebrated with a wonderful drive though the Adelaide Hills...

Week 6 to 10 Xmas & New Years

Too many X-mas parties...
I lost the momentum of the weekly updates as weekends away as well as Xmas parties affected the progress a bit. But on the other hand days off work helped here and there. Anyway hope you enjoy reading my progress over the last 5 weeks.

Engine oil cooler hose

The lower engine oil cooler hose, that goes from the oil pump to the oil radiator, was very porous. Therefore a consistent oil leak, that would drip on my new suspension rubbers... not an option...
Forum friends suggested to not even ask MB for a price, just go to a hose place. So went with my old hose to Enzed here in Adelaide and they made me a new hose reusing the couplings for about $70 while I was waiting! How good is that...
I just replaced the porous one, as the other one, from the top of the radiator, to the next the oil filter housing, is impossible to get to. In hindside it would have been quite easy when the front axle carrier was off, but that's another story.
So for now, no more oil drips from this corner of the car...

Front suspension

It was time to tackle the front suspension job. As I stated before the car 'drove like a boat', while these car were in their days famous for their 'suburb' and 'crisp' handling. Time to get some of this back. My shopping list was the following:

- Upper wishbones including ball joints
- Upper and lower control arm bearings/bushings
- Lower wishbone ball joints
- Bilstein shock absorbers
- Front axle torsion bar rubber bearing, clamps & links




When fitting, especially the axle-carrier to body rubber mounts the Mercedes-benz workshop manual refers to Napthalen (000 989 04 60) to lubricate the rubbers when remounting. After some research found that this is castor oil grease, meaning it is not petroleum based, rather plant based. In the local Repco found PBR Rubber grease that is just the same thing...

To remove the control arm bushings, you need to make a tool. I'll place a photo of this later. Basically a M12 tap end, with a receiver and a number of rings and bolts, so you slowly can pull the rubber out of the control arm.


Front Axle Carrier to Body mounts

These look like they have never been replaced... very dried out, torn and basically not rubbery at all...
Had to use a engine hoist, to keep the engine in its place, while dropping the axle carrier. The role of the axle carrier is basically that the body rests on it, with the mounts we're replacing, then the engine also rests on this, while it is supported by the control arms and wheels.

Getting the springs back in between the control arms was a tricky job. Although I had the appropriate inner plate spring compressor, the plates have to be placed just right, otherwise either the upper one is stuck in the housing or the lower wants to twist so much that it cannot be undone. Anyway the first took 4 goes and about 3 hours, the second was first go and less than half an hour.

Engine mounts
The engine mounts were incredibly dry and worn so these had to be replaced. It only made sense to also replace the engine shock/dampers. Well I'm glad I purchased the new ones, as the old ones once removed had no damping what-so-ever left in them! 

The removal of the engine mounts should have been as simple as removing the 19mm bold after removing the spark plug lead above. In practice the years made it quite hard and no WD40/impact gun etc was going to fix this. So I just undid the shocks/dampers and left the engine mounts for later to worry about. As I also wanted to replace the front axle rubber mounts, I found later that when I unbolted the front axle carrier (supporting the engine with a hoist), the carrier was hanging on the dried out engine mounts.
So just some wiggling teared the engine mounts in two and gave me access to the engine carrier (the arm that connects the engine to the engine mount). This was bolted to the engine with 4x12mm bolts and the impact gun did this with ease. Then the engine carrier arm, could be placed in the workmate, and then the 19mm bold came off easy...


Mounting the new engine mounts while the axle carrier was removed was quite easy. For the engine shock/dampers I had to make a special tool. The new rubbers needed to be squeezed quite a bit for the nut to go on. There is no way in fitting the nut without this tool.
I used a cheap 100mm door hinge, removed the pin, drilled a 22mm hole for the nut and socket, and a 12mm slot to slide over the piston. I connected these with two 50mm M6 bolts and wing nuts and the rubbers could be squeezed. As you can see there is quite a bit of tension but it did the job...

Steering

Although in the maintenance records it showed that the Power steering box was overhauled, cleaned, resealed and painted only 8 months ago, the steering was still very indirect.
Inspection showed that the rubbers on the tie rods were torn, therefore probably caused dirt to go in and grease out of the joint, creating play and a bad steering feel so these had to be replaced. While I was at it, also replaced the drag link and the Steering damper. I purchased an idler arm repair kit but did not fit at this stage as this seemed still fine.

Front brakes & Wheel bearings
While the front hubs were removed it made sense to overhaul the front brake system. Luckily I have a mate that works at a brakes place here in Adelaide. He organised an incredible deal where I only paid trade price and no labour!!! I got the discs, pads, piston and brake hose replaced. The calipers were rebuilt including sand blasting and respraying. They look new! They also replaced the bearing cups so I could fit the hubs back with nice new bearings. All in all, a fabulous job and quite an important one.


Timing chain
On the forums a lot of members are talking about horror stories of the timing chain. The tensioner timing chain guide can break, the chain can slip off and a lot of damage could be done inside the block. In addition to this, as the chain stretches the timing is out and a lot of horsepower is lost. So time for a check.
I removed the left valve cover to reveal a perfectly looking timing chain guide engine tensioner. So cleaned up the cover and refitted with a new gasket and some ease of mind.


Next on the list:
Remove the seats, clean the rails, vacuum the carpets underneath, fit the new sheepskin covers and remount the seats, moving the driver side to the lowest mounting holes.
Get a wheel alignment done.
Go for a careful drive, burning in the brakes and then recheck all the torque settings on the suspension parts.
Finally finish the transmission oil change
Replace the rear diff oil
Replace the fuel filter and all its hoses.

Week 5 Clean & Polish

Hi Guys,
This week went a bit different than planned. Although I knew that I would not have much progress on the car due to the workshop floor being painted, suddenly I found myself polishing the car to deliver St Nicolaas to his birthday party at the Dutch club here in Adelaide. But the car came up beautifully...


Speakers
The new 10cm / 4" speakers arrived. The shape as you can see in the picture on the left was slightly different where the original have quite small 'ears' for the mounting, and the new ones have staight sides. This was not a problem for the speaker hole next to the steering wheel, but the hole next to the dashboard cupboard was too tight, and I had to cut some of the steel from the new speaker to make it fit.
So if you are looking at replacing yours, make sure they have little 'ears' so they fit quicker.
But I'm not really happy with the fit as the hole in the dashboard is larger (vertically) than the speaker (old or new), allowing air to short circuit (semi open baffle). This makes it impossible for a small speaker to produce any kind of base, so I will be addressing this later with some filler and polyethylene tape. Of course you'll never get proper base from such a small speaker, but it will not be that hard to make it produce more low than it does now.

Interior clean up
The interior has been hiding underneath factory sheepskin covers possibly since the delivery date in 1978. This means that there was a lot of rubbing and it took quite a while to get it clean, but the result looks as good as new...










The back seats cushions are very flat. Not sure how much padding should be in here, but surely more than it has now...
Also found some rust underneath them. As there is nowhere to go for rain that would have come in at some time, I'm not surprised... I'll treat this later with some rust converter and probably put a drain hole in.

Timing chain postponed
Got some prices. Basically $350 + postage from US, about $600 from Australia and $1000 fitted. Will look at this soon as I am scared by the horror stories of a failing chain, but this will be at least a couple of more weeks before I'll even order the parts. First the suspension, the brakes etc. Oh, and a good number of hoses. I've been told that I should at the very least do all the high pressure petrol hoses. As these go over the engine a burst can have quite disastrous consequences...

Accelerator pedal

This is a new job added to the list. The pedal was no longer mounted to the floor.

It's supposed to be attached to a bracket that is welded onto the floor. Then it hinges from this, while at the top a sliding eye transfers the movements onto the linkage.
The bracket is no longer (completely rusted away). This seems a very common problem (remember the car is 33 years old) and a new Steel bracket as per photo on the right is simple to make and can be welded or pop-riveted into the floor. As the floor mats do hold the accelerator pedal enough in place for now, there is no large hurry. Somewhere in the next couple of months is fine.


Polish and clean
This took the biggest part of the Saturday but I am very happy how the car shined up...



What a huge job this was... Although not planned yet, it is actually timely as I expect the new seat covers next week.

Service records
Created a spreadsheet from all the service records and invoices. I was pleased to see that the car was regularly serviced... For fun, I created a chart to see the actual mileage per year as taken from the service records.
The red arrows show when the second owner took ownership and when I did. They both plateaued before the sale.

Next week
I should be receiving the new lambs wool seat covers. The second half of the workshop floor needs to be painted and although a good mate of mine is doing the painting, it stops the process of working on the car. Next weekend is mainly Xmas parties, so I won't promise too much ;)

Cheers,
Marco