One of the things that became apparent in starting to use the car regularly, was that the differential had a fairly major leak.  This is obviously bad for the longevity of the limited slip diff, but on the XJ series cars, the rear brakes are inboard so major leaks can impact the rear brakes.

The independent rear suspension used on the XJ and Daimler derivatives is the same independent rear suspension unit introduced on the E-Type in 1961.  It was still far ahead of everyone else when the X was introduced in 1968, and continued to be throughout the 70s and early 80s.  It was only when the competition introduced multi-link rear suspension systems in the mid 80s was it surpassed.  The original version was used until the end of XJ Series 3 production, and evolutions of the system were used until the mid 2000s.

The reason the independent rear suspension for the XJ is related to the differential is the design of system has the entire rear suspension, differential and brakes in a removable rear subframe.   Therefore to fix my differential leak, the rear suspension had to come out of the car.

On my car the exhaust system wasn’t in great condition and had to be cut before the rear suspension could come down. This will need to be replaced later. The good news is that the underside of the car is in good condition. With the rear suspension removed, the differential could then be serviced. A clunk in the rear suspension was traced to be due to bent trailing arm mount brackets.

While the car was in having the differential leak fixed, a few other things needed sorting out, including:

• Leak from transmission pan gasket
• A couple of small coolant leaks from coolant hoses
• The fan clutch was not engaging properly when the engine was hot

In addition to those things, when changing a fuel sender on the left hand tank, it was clear that the cleaning the tank a few months ago hadn’t worked very well.  The tank was still very dirty.  New fuel tanks are still available, so I was able to purchase one and have it sent directly to the workshop to be fitted.   I had feedback it looked like it was very good quality and had some kind of internal ceramic coating.

The front brakes were leaking and so the calipers removed to be rebuilt.  In doing so, it was clear that it was necessary as the pistons were in pretty rough shape.

I also had some new external rear view mirrors fitted, including one on the passengers side.  This wasn’t optioned when the car was new, but I park very close to a wall in my storage area and I don’t want to damage the side of the car.

It as a lot of work on the car, but none of these things are all that unusual for a car that was laid up for a while.

The post Daimler differential leaks, front brakes and fuel tank appeared first on Classic Jalopy.

• Soft brake pedal
• Dirty passengers side fuel tank and pitted chrome on fuel cap
• Dented rear bumper
• Tachometer not working after my attempted repair
• Fuel gauges not working properly

The soft brake pedal seemed to be resolved by cleaning up the calipers and getting the pistons moving a bit better, and then re-bleeding the brakes.    The passengers side fuel tank was a bigger job.  It had to be removed from the car, and it was clear it had been out before and been re-sealed in some way.  It was a bit rusty inside and some of that sealer was flaking off.   The tank was cleaned in acid and then put back in the car.

The drivers side was in much better shape.  Since the rear bumper comes off to get to the petrol tank, the dented section was replaced with a better one.   I also had a better chrome filler cap to replace the pitted one with.

It turned out I had done the tachometer wiring correctly.  However, there were some issues with the wiring at the back of the Tachometer which once fixed had it working properly.

During this service, it was also identified that I would need to bring the car back in the new year to address a major leak from the differential, and that one of my fuel pumps was not working properly.   I planned to replace that myself.

While the car was in, it also had an oil and filter change and other checks.

The post Daimler Servicing appeared first on Classic Jalopy.

The main difference between a tank from a petrol W123 and a diesel is the petrol cars had the swirl pot at the bottom of the tank.   The swirl pot allows fuel to continue to flow even during hard cornering, as the return line not only keeps the pot filled, but draws fuel in from the rest of the tank.  Presumably the diesels don’t need this as they flow a lot less fuel and are less likely to do hard cornering.   In addition, an algae outbreak could clog up the little hole in the bottom of the pot.   I’ll be using the biocide additive on my car regularly, so I’m not concerned about this.

When the tank arrived, I was really impressed with how clean it was.  I couldn’t see any rust at all in the tank. The petrol fuel strainer was also quite clean.  Since I don’t want to do this job again, I gave it a clean and was able to get some of the normal residue out of the tank before installing it.   I used my pressure washer to clean inside the tank as best I could, then dried it with my cordless blower.   After that, I used some methylated spirits to make sure I got the last of the water out.

I came back the next day to prepare the tank for installation. I installed a new diesel fuel strainer.   The diesel strainer has a coarse mesh, to allow minor algae to get through and be caught in the pre-filter which is easier to change.   This is part 124 470 01 06.   I also re-installed my fuel sender.   Mercedes thoughtfully made both of these items use the same 46mm hex.   I also had to glue on the rubber ‘foot’ that sits around the strainer and between the tank and the body of the car.

Re-installing the tank was easier than getting it out.   The only slight hiccup was the rubber ‘foot’ had been somewhat dislodged and I had to use screwdrivers to reposition it from under the car.

Once the tank was in place, it was a fairly simple matter to install a new fuel supply hose.  The car was using the fitting from the original hose, with a normal fuel hose clamped to it.  There probably isn’t anything wrong with this, but I bought the proper cohline hose.  It is for multiple cars, so I had to trim a few cm off for the W123 diesel.

Next was the return line and breather hoses.   The EPC states that these hoses are both 120mm.  I cut 120mm hoses, but I found the return hose was too long and I trimmed a few cm off it.   The breather hose was also thicker.   I didn’t actually install the breather hose at first, I waited until I had the car running so I could move it to the hoist under its own power.   I had bought the proper hose clamps for the engine bay and the supply hose, but forgot these two, so had to use the regular hose clamps here.

While I was at it, I also replaced all the hoses and filters in the engine bay.   The pre-filter was quite dirty, and needed replacement.   The main filter probably wasn’t, but I replaced it anyway.  I also used the proper hose clamps that don’t bite into the hoses.   According to the EPC, the hose from the supply line to the pre-filter is 140mm and the hose from the pre-filter to the lift pump is 40mm.

The EPC also lists a special return hose some people refer to as the ‘Cigar’ hose.   This is part number 000 997 51 52.  A lot of people don’t seem to bother with it, but since I was ordering new parts I got one.  I found it to be very long, and I had to push it a long way onto the return hard line so it didn’t kink.

At this point I was ready to refuel the car.  I had 30 liters of diesel I had pumped out of the car through a filter, so I added this to the tank.   I was happy to see there were no leaks and I began to prime the system.

The primer pump felt very odd, and I couldn’t work out why it didn’t seem to be moving much fuel.   After about 30 minutes of trying various things, I noticed that one of my hose clamps was stopping it from going all the way in.   Simply rotating this clamp restored full travel to the primer and I was able to get quite a lot of fuel moving.   I think my issues priming the system last time were due to my blocked strainer, as I was now getting quite a lot of flow.

It still took quite a few times of priming the system, trying to start the car, priming the system, and trying the start the car until it finally roared into life.   It ran well and seemed to be idling better than before.  I wonder if it wasn’t getting enough fuel with the blocked strainer.

A quick test drive around the factory complex showed no leaks and the car running well.   The downside was that the A/C had stopped working, which I will need to attend to.

Since I was happy with how the car was running and there were no leaks. I re-installed the boot trim, and left an Easter egg for a future owner on the fuel tank.

I will check the condition of the fuel pre-filter over time, but I expect that with all this work my fuel delivery problems should now be behind me.

The post 240D algae part 7 – Installing a new W123 fuel tank appeared first on Classic Jalopy.

When I returned 24 hours later I realized my mistake.   It would have been a second to pull it out the day before but even after 24 hours it was stuck.    Try as I might, I was not able to pull it out, even putting my feet against the tank and pulling back with all my weight.

A couple of days later I came back with a new plan.  Instead of pulling it out, I would push it through.    I hammered through a couple of thin drill bit.  I thought this might break the bristles off the walls of the tube, allowing the pipe cleaner to be pulled or pushed through.

It wasn’t to be.  After using a slightly bigger one, it managed to break off.  I then used a punch to try and hammer it through, but the tank was so well sealed it just went through the walls of the return line.

While it is probably possible to cut out this part of the tank and weld a new section, I don’t have the skills for that.   So I am now on the lookout for another W123 diesel fuel tank.   It’s a shame, as other than rust at the bottom this one was in reasonable shape, and it looks like it was an 80 liter tank from a later 300D.

It is rather annoying as the car is going to be off the road for far longer and I am up for the cost of another tank.  However, mistakes like this are going to happen from time to time when you take on jobs like this yourself instead of taking to a professional.   This is is why I try to take on things that the ramifications of a mistake are fairly correctable.  For example in this case a 2nd hand tank vs an engine rebuild.

I don’t regret trying to seal the tank, my mistake was not making sure all three openings were clear.

The post 240D algae part 6 – How I ruined my W123 fuel tank appeared first on Classic Jalopy.

One of the things that got me over the line was that the tank does not have a swirl pot like the petrol engine cars.   On the petrol cars, I would be worried that the sealant would block the small hole in the swirl pot that lets fuel from outside the pot be drawn inside.   On the diesel, I would not have to worry about that.    I’m actually kind of surprised there are no baffles or anything like that to stop the fuel sloshing around during hard cornering.  I suppose the assumption is that diesel drivers don’t do stuff like that.   Challenge is that many of these cars were taxis and clearly the MB engineers never met a Sydney taxi driver.  I’ve even taken my car on a lap of eastern creek raceway.

Sealing the tank added another week and a half to the project.   You can’t just buy the tank sealers at Repco or Supercheap, so first it took 3-4 days to arrive.    The sealers are also part of a three stage process, which adds time.   I went with the KBS Gold Tank sealer, primarily because I could buy the parts individually and they had the sizes I wanted.   The POR15 product required me to buy an entire kit for over $200.   The first stage is a strong degreaser that I already have.   Then there is the rust converter, then finally the sealer.

I bought the KBS Gold rust converter and then the sealer.   While I waited for the new products to arrive, I used the degreaser.  The tank was already pretty clean but it did seem a little cleaner after that process.

The rust converter and KBS Gold coating arrived yesterday, so after my kids went to bed, I went down to start the process.  The first step was the rust converter.  Since most of the rust was in the bottom of the tank, I needed a way to make sure it did not run out of the drain hole.  I took the old fuel strainer and broke off the mesh part, and then used a bolt, washer and nut to turn it into a makeshift cap.   I also used a wire cleaning brush to mostly block the return line.

The instructions called for a minimum of 20 minutes using the rust converter, moving the solution around every 5 minutes.  I ended up doing about 35 minutes and while the tank was fairly clean, I got some minor rust debris out once I removed my makeshift plug.

Once the solution had drained, the tank had to be washed out a few times and then fully dried.   Washing it out was fairly easy, but drying was a slow process.   It took about an hour using the small 18v blower I use to dry the car after a wash.  I stopped every 10 minutes or so to peer into the tank with a torch to see where I had to direct the air.   I also used a paper towel that I rolled up long and thin to dry the low area around the strainer opening.

It took about an hour to get the tank dried out.

Next step was to start the process of coating the tank.   I put my makeshift plug back in the hole for the strainer and made a funnel out of an old coke bottle.   I wish I had put gloves on at this point.  My hands are still covered in the paint.

Basically the process is that you’re supposed to coat the insides of the tank by rotating it around to get an even coverage.  Than after about 30 minutes drain the excess.   I coated the bottom and the sides, but didn’t want to clog the breather, so didn’t coat the top.   I was left with maybe 100mls in the bottom which took an eternity to drain out.  The drain hole has a lip around it.   After a lot of rotating the tank, I got about 90% of it out.  I then tried to angle the rest so it dried into the seam of the tank.    The whole process took about an hour and a half.

I now need to leave the KBS Gold sealer to cure for 96 hours.   That means I can refill the tank over the weekend.   I also suspect I may have an 80 liter tank instead of the 65 liter tank the car came from.   I’ve had a look at pictures of the tanks online.  The 65 liter tank seems to have a different shape.   I’ll be able to measure it when I refill it later.

The post 240D algae part 5 – Sealing the W123 fuel tank appeared first on Classic Jalopy.

On my last article I had some good advice on how to clean the W123 fuel tank.   Armed with this, I used part of a steam mop to act as a steam cleaner on the tank.   Apparently the steam kills the algae.

I found that the attachment for the steam mop was the perfect size – fitting exactly into the hole for the fuel sender.    This allowed me to put the fuel cap on the W123 fuel tank, sit the tank over a catch container and introduce a lot of steam into the tank.

I spent about 20-30 minutes pumping steam into the tank.   This seemed to soften up the debris at the bottom of the tank, so I put the end of my pressure washer into the fuel sender orifice and was able to blast out the rest of it.   By moving the angle of the pressure washer I was able to get reasonable coverage of the tank and my catch container soon filled up with horrible dirty water from inside the tank.

It was also suggested to use methylated spirits to get the water out of the tank after I cleaned it.   I only had one bottle on hand, and used it to give the tank a good rise.   The next day I came back with some more and rinsed the tank even further.

at that point, looking inside the tank looked far cleaner than before.   Now most of the gooey residue was out, I could see that while the W123 fuel tank was mostly in good shape there was a little bit of surface rust at the bottom.   This is because water is heavier than diesel, so the water sits at the bottom and rusts the tank, and allows the algae to grow.   At least now I have removed nearly all of that.   The picture shows the area of the tank below the fuel sender.   It is a bit worse on the other side, but I have no way of photographing that.

Once I let the tank dry a bit, I used my battery operated blower to dry it out some more.  After blowing a lot of air into all three orifices, I was able to get the tank looking pretty dry inside.   Any leftover liquid should be mostly methylated spirits, not water.

At this point, I also gave the area where the fuel tank sits in the car a bit of a clean while I had easy access to it.

I think I now have the tank as clean as I am going to get it.   I’ve not yet decided if I should use a product to coat the inside of the tank given there is a bit of rust at the bottom.  It’s not too bad, but it’s easier to do it now while the tank is out.   I didn’t see any rusty flakes when I was draining it.    At this stage I am probably leaning against it.

The post 240D algae part 4 – Cleaning the W123 fuel tank appeared first on Classic Jalopy.

Previously, I had determined that the fuel strainer was blocked and pumped out 40 liters of diesel into fuel cans.  I assumed there was not much left.   My next task was to see if I could remove the strainer.

A couple of weeks ago, it was a rainy Sunday and my three kids were bored.  They were keen to come with me to my little warehouse unit and help me out on the cars.   The first step was to get the 240D out and up on the hoist.   The three of them were quite pleased that they were able to push the car out on its own.  Then I showed them how to use the positioning jacks to spin it and position it properly for the hoist lifting arms.

Next was to get the car up into the air and drain the remainder of the tank.  We used a tool to stop the flow of fuel as we disconnected the main fuel hose.  I wasn’t sure how much diesel could flow through the blocked strainer, and didn’t want a face full of it as I disconnected the hose.  It turns out I needn’t have bothered, as only a thin trickle of fuel was able to get past.

We let the fuel drain slowly into a bucket.   We were seeing some debris come out as we drained the fuel, although not a lot at this stage.  I had previously purchased a 46mm socket online.  It required a 3/4″ drive, and so I also purchased an adaptor.   Trouble is, I lost the adaptor and so my new socket was totally useless.  By then the kids were bored and we left the car to drain into the bucket.

A couple of days later, I went back and the bucket had just slightly overflowed.  There was more fuel than I figured in the tank, but I was lucky that it was only a tiny bit more, as there wasn’t a very big puddle around the bucket.   There wasn’t a whole lot of clearance around the strainer, so instead of buying another adaptor, I bought a different 46mm socket that could use a regular ratchet.

Even with that and a wobble extension, it was hard to get enough grip on the strainer.  Even when I could, and using a long breaker bar, I was unable to get the strainer to move, the socket would just come off.   I spent (or wasted) two evenings trying various ways of getting the strainer to move.

Eventually a friend told me that taking the fuel tank out of his W126 was surprisingly easy.   The W123 is quite similar to the W126 in that regard, so I decided that I would remove the tank.

Yesterday I went and started that process.  It really wasn’t so bad and I should have done this earlier.   I found this article from dieselgiant the best.   It is quite simple.  While the car was still up in the air, I removed the hoses for the return line and breather.  They were quite hard, so I will replace them.   according to the EPC, they are both supposed to be 120mm in length.

Next with the car on the ground, the divider panel comes out with an 8mm socket.  There are four bolts.   There is no need to remove the carpet backing.   Most of the guides tell you that you need to remove the first aid box and disconnect the sender from the top.   I didn’t, and it was quite easy to remove it from the boot.

It looks like the tank will clear the vacuum reservoir that sits above it, but it won’t.   It is held on by a plastic fastener that I removed with a trim removal tool.   There is enough slack in the vacuum line to put the reservoir to the side.   I also found it easier to remove the right hand side boot liner, which is moulded plastic.   There was one plastic fastener below the tail light.

Its a bit fiddly to get the tank out due to the filler neck.  I found using a pry bar on the right hand side of the tank, as I pull it out from the left was the easiest thing to do.

Once I got the tank out, I was able to use the breaker bar and my 46mm socket to get the strainer out.  It was not easy, I doubt I could have done it from below, had I kept trying.   The fuel sender unit was even harder.

It was also interesting to discover that a used fuel tank was installed some time after 2005.  The replacement tank was removed from a 300D 18/06/05.  It is in keeping with this being a fairly low mileage car that saw limited use.

On removal, it was clear why the car was not running well.   The strainer was coated in black gooey algae.   Its surprising it ran at all!   The sending unit on the other hand was very clean.  On inspection, the sides of the tank are also very clean, there is just a layer of gunk on the bottom.   I used a couple of small brushes I had on hand to clean around the area near the strainer, but I want to find something better before I re-install the tank.    I’m not too keen to use water, as I don’t want to contaminate the fuel or cause rust issues in the tank.

My next steps will be cleaning the tank more, and then starting the re-installation. This will include cleaning up the area where the tank goes.

The post 240D algae part 3 – removing the W123 fuel tank and fuel strainer appeared first on Classic Jalopy.