| While I was replacing the fuel pump on my E-Type I noticed some hairline cracks in the fuel hoses. This was obviously a problem waiting to happen so I ordered a new set to replace them. It is probably cheaper to buy the raw hose and adapt the original fittings, but SNG Barratt sell a kit with new hoses complete with fittings that is much easier to fit. Postage is quite slow at the moment, so it was a few weeks before I finally got the hoses. The cracks opened up even more as I removed them, so it was definitely worth it. There are two E-Type fuel hoses the back of the car, with banjo fittings at each end. One from the tank to the pump and one from the pump to a hard line at the front of the car. There is an additional hose from the hard line to the carbies but I was not replacing this one today.  The E-Type fuel hoses are quite accessible once the lining is out of the boot. I already had it out to do the fuel pump. It is worth buying new crush washers when replacing these hoses. I didn’t think to order them and should have. One of them was in quite bad condition. I tried Supercheap Auto but they don’t sell this sort of thing. There is a new Bursons near me where a very helpful lady found the exact match I needed.
 One of the is a bit longer than is necessary, but there is room for the slack. Once I sorted out the crush washers, I had no leaks with the pump running and the car idling. I will take the car for a short test drive in the next couple of days to make sure that there are no further leaks.
The fuel leaks have damaged the paint in the spare tyre well. I don’t need it to look pretty as this area is not visible, but I will have the paint repaired so I don’t get rust here. I am looking forward to a nice long drive in the car without fuel leaks now the weather is nice and lock downs are finished. I have been working on a project to eliminate the monovalve from the climate control system in my 560SEC. In the last part I had almost completed the cooling hoses required for the job. I had mostly worked out hose routing I was looking for – which was combining the dual outputs from the heater core into a single hose where I could place the new heater valve. Looking further my design wasn’t going to quite line up. Once I put the elbow piece on the end, it was too long and the hoses were bent too much. I didn’t have the clearance to have another join between the heater valve and the engine block. My solution was to use some hose offcuts to try and find a single hose that would join from the engine to the heater valve and replace the factory hose. I created this, tested it and based on it working, I went to Supercheap Auto to find a hose that matched as closely as I could. In the end a hose from a Toyota Hilux LN106R 2.8 I4 Diesel fit well. I just had to trim off the ends to use the bend that I needed. The fit is not perfect, but it is close enough that it is not putting too much pressure on the hose.  I didn’t want to use the joined up bends because the place where the join needed to go was where the hose went through the firewall. The clamps may have chafed against the firewall. The single piece should work much better. Once I get a few more parts I will be able to re-install the radiator. From there I can make sure I don’t have any coolant leaks.
 From there, I was able to install the heater valve and join it to the engine block. Next step will be install the solenoid and vacuum connections. The hoses will be eventually hidden by one of the control boxes. I think it is for either the ABS or the CIS-E system.
A few friends in the Mercedes Club and I have been trying to get a monthly night drive going. Last night was the third one and yet again we had a great drive. This time we met up in Kirrawee and the drive was through the national park to Bulli. We started out with 5 cars and based on the cars that participated, it was a celebration of the Mercedes M116 and M117 V8. There was at least one of every generation represented. We had a 280SE 3.5 with the original iteration of the M116 – in 3.5 liter form with the D-Jetronic fuel injection. Then there was my 450SLC with the second generation of this engine, a K-Jetronic 4.5 liter M117. For the third generation we had a 380SEC with the 3.8 liter M116 – the first of the Alloy engines. Finally we had a pair of 420SELs sporting the fourth and final generation of the M116 with the CIS-E fuel injection. Interestingly all of these cars have pretty much identical peak power figures of around 200hp, although the torque figures and gearing vary greatly. The M116 was Mercedes first mass production V8 and ran from 1969-1991. The M100 came first but it was always a low production, specialty engine. The M117 is identical for each year other than a longer stroke and hence larger capacity.
 We then proceeded towards waterfall before entering the national park for a nice windy drive to Bulli – taking in the sea-cliff bridge along the way. At Waterfall we managed to corral a BMW 735iL (E32) along the way. I’ve done that road a few times, but never at night. Doing the road at night is a totally different experience, less traffic and more concentration on the road.  We met up at Bulli before coming back via the motorway. The motorway was completely empty on the way back. My 450SLC performed well for most of the drive, especially on the twisty bits and the motorway. The new injectors have really made a huge difference and they will probably pay for themselves pretty quickly with the vastly better fuel consumption I am now getting from the car.
For the second time on these night drives I had car trouble on the way back. I had to stop suddenly suddenly when I was going through Ramsgate. After that I had a very spongy pedeal. My cars are dropping like files and the only one I have available to use now is my 1986 300SE. I won’t be driving the 450SLC until I can investigate further. I hope to have the 560SEC ready for next month’s night drive. The Mercedes Club hold a mid-week drive pretty much every month. I’ve been a member for more than 10 years but never managed to attend one. I had a free day today and the drive looked really good. This months MBCNSW mid-week drive was up to the Hunter valley. The route was via the Putty road, which I’ve done a few times before. Mid-week is a great time to do this route as the Putty road gets very busy with motorcycle groups on the weekend. These also attract highway patrol. 
Attendance was pretty good for a mid-week event. I took my 450SLC. The 450SLC is well suited to this route, but the choice wasn’t really much of a choice, as only the 300SE and 450SLC are up to a longer drive at the moment. The 250SE is not charging so would promptly run out of electricity. The 560SEC is currently without a radiator or coolant hoses, and the 560SEL is having some minor panel damage repaired. Exacerbating this situation is the long shipping times due to Covid19. As well as my SLC, at the MBCNSW mid-week drive there were two other 107s – a 380SL (with a 5.0 engine) and a 350SL. Sadly the 350SL failed to proceed early on. It was belching out black smoke and the owner thought he might have a batch of bad fuel. I sure hope it was only that! There was also a 380SEC and a manual 190E, which are quite rare in Australia. As well as the classics there were three moderns, a C Class, an E class and an SLK. 
The route started out taking us west, towards Richmond. From there we turned off at Comleroy road, and then at Blaxland ridge road. These are both roads I am quite familiar with, using them to come back from the mountains and avoid the M4 or M2. We then joined the Putty road, the original way to the Hunter. The Putty road has some twisty sections and some long straights. It is nice to drive it without bikes up your tail every few minutes. We took the Putty road right up to the hunter and then turned for Broke. There is a slightly faster way to go for Broke, but the road is not as good. We had a rather nice lunch at Harrigans Irish Pub and then a few of us took a rather spirited drive back via Wollombi and Central Mangrove. It was really good to get the SLC out and stretch its legs. I suspect both my SLC and the 380SL 5.0 will need new fuel accumulators as they both struggled to start when warm. I’ll probably need to replace the transmission mount. I have not yet inspected it, but from the vibrations I was feeling I am pretty confident it is collapsed. My 560SEC has been leaking from the power steering and self leveling suspension. In both cases, it is obvious that (at least some) of the leakage is coming from the low pressure hydraulic hoses. It is possible there are additional leaks in the steering, but fixing this obvious one is a good place to start. I had looked at doing this job a couple of months ago. I quickly saw it was quite fiddly and as I was planning to use the car the next day, I decided to put it off. Once I realized I would be removing the radiator this seemed the perfect time to do the job as there would be a little more room. Unlike the high pressure hoses on the output side of the pump, the low pressure hoses are just standard hoses and are on the input side of the pump. The first one I did was the power steering hose. I had previously ordered a meter of the Mercedes power steering hose, which should be enough to do 3-4 cars. I’ll need to do this job on my 300SE at some point. Doing this job is a good time to change the power steering oil. Even better, if you have an assistant to do a flush as well. The pump runs at too high a pressure to do it on your own. Because of the position of my A/C hose, I found it easier to remove the elbow fitting, as can be seen in the picture below. The flexible hose is quite short and joins up to a hard one in the frame below the P/S pump. The old hose allows for the new one to be cut to the proper size. In the photo below you can also see the hose for the self-leveling rear suspension which is very wet. 
My hose was not in horrible condition, but it had been weeping out of the hose material. The new hose and the size required can be seen below. The EPC lists the exact size, and for example the 300SE needs a slightly longer one. 
The new hose is quite hard to get on the hard line, and the clamp further tightens it on. I am not expecting any leaks here! I found my battery cable cutter the easiest way to get a good cut on the hose. One of my hose clamps got broken on removal so I will need to replace it later. The hose for the Self-leveling suspension was in a really bad way. it was leaking quite badly out of the fabric cover, and the hose made a crunching sound, indicating that the inside of the hose had completely failed. I found the easiest way was to clamp off the hose and cut it, so I could remove the reservoir. As I had flushed the system recently, I didn’t plan to evacuate the fluid. 
The bracket for the reservoir was a bit crusty and at some point I should do something about it. I don’t think it is supposed to be painted, I think it is supposed to be anodized. I will have to check. The hardest hose clamp is the one that connects to the SLS pump. I needed to find a screwdriver that was the right length and head type. Too long and the fan got in the way. Too short and I could not grip it properly. I think I had nearly all the Phillips head screwdrivers in my toolbox out until I found one that did the job. I used fuel hose as a replacement as that is basically what the braided hose is. Again, I was able to use the previous hose to determine the required length. It was a bit of a fiddle, but I was able to use my finger to stop the oil coming of the top of the reservoir as I turned it on its side and swapped the hoses out. I then used the hose clamp to stop leakage until I had pushed the other end of the hose onto the hydraulic pump and tightened up the clamp. 
I am hopeful that these new hoses will fix some of the worst of the leaks on the SEC. Especially the SLS hose, that one was particularly bad. I will be performing the same jobs on the 300SE at some point. As part of the work I have been doing to the 560SEC, I have removed the radiator. The radiator was leaking from the top tank and appeared to be original. It was an IMI unit which was one of the OE suppliers and had a 1987 date code on it. W126 radiator removal is fairly straightforward. Fist step is obviously draining the coolant, and there is a drain valve at the bottom of the radiator. The coolant will drain must faster if the radiator cap is off. I am really happy with how clean the coolant is, and how little residue there is in the cooling system. A big contrast to my Citroen DS and the years it spent in South Australia. At the top there are a couple of metal clips that are easily prized off. Mine had gotten a bit rusty, so I will be replacing them. There are clips that hold the radiator on, and that hold the fan shroud to the radiator. The W126 radiator and fan shroud cannot be removed as a single unit. The shroud must be pushed back a little so the radiator can be withdrawn and then the shroud removed separately. There are six hoses that must be removed. At the top there is the main hose to the motor and the small overflow hose. They are removed in a matter of minutes with hose clamps. As they are at the top and do not get moisture flicked up from the road they are generally in good condition. The bottom is a different story. There are two coolant hoses – the main hose to the engine and the smaller hose to the remote tank. I found that my clamps had rusted in place. For the main hose, I eventually got it free with some penetrating oil and using a socket on the hose clamp instead of a screwdriver. In the end I had to cut the smaller hose. I will be replacing the hoses, but was hoping to keep the current ones as spares. The other two hoses are for the transmission oil cooler. The end of my hoses looked really rusty and they were not wanting to move. Given their age, I ordered some new ones and removed them at the other end which, thanks to oil leaks around the engine, were rust free. As I was not going to keep the hoses, eventually I got the other end off after more persuasion. Of course, removing the hoses at both ends means a big mess under the car as it is hard to catch all the oil drippage. Cleaning up oil spills is a good use for Murdoch newspapers. From there it was a simple matter of sliding the radiator out past the shroud. The A/C condenser remains in place, so the freon does not need to be evacuated. There is nothing obviously wrong with the old radiator, but the new one certainly looks much cleaner.  The radiator and shroud out of the way gives a little bit more room to replace the low pressure hydraulic hoses for the power steering and self leveling suspension. They are both leaking and will be the subject of the next part in the series.
My 560SEC had been leaking coolant and giving me heat when I didn’t want it. Last week I started the repairs for these problems. As the Bosch and Mercedes W126 Monovalve repair kit was no longer available, I have been installing the Klima Design Works monovalve elimination kit. In the first part I removed the W126 monovalve, auxiliary water pump and other hoses. This gave me the room to give the area underneath the heater hoses a good clean. There were some leaves and other detritus. Its important to remove this stuff it can cause rust. The mud stays wet far longer than if the area was clean. 
The picture above shows the cleaned area. It also shows the space I am going to fit the new components. The two outputs from the heater core are seen on the right, and the hose back to the engine in the middle. The bracket where the W126 monovalve used to go is on the left. My plan is to use a T-piece to join the two outputs, run the coolant through the heater valve, and then place the vacuum solenoid where the W126 Monovalve used to go. 
The picture above shows the setup I plan. I have a few more hose clamps on order before I can fit this. The clamps that went on the W126 monovalve side were too large. A vacuum line will go from the end of the valve back to the solenoid and the whole thing will be covered up my the control box that was there before. I used new heater hose except for the bend, which was in good shape.  Once the new hose clamps arrive, I will finalize this assembly and then move on to changing the radiator. The new assembly is slightly too long but the flexibility of the hoses should hopefully allow it to work.
My 560SEC has been having a couple of problems with its cooling system. Coolant has been weeping out of the top tank of the radiator. In addition, the monovalve has failed, causing unwanted heating at idle. The radiator looks either original or replaced very early in the cars life. As these radiators have plastic tanks, I have purchased a new one to replace it. It used to be possible to purchase a monovalve repair kit from Mercedes or Bosch. The supply of these has now dried up. There is a kit from a company called MTC but all the Mercedes Forums and facebook groups are litted with stories about how this part never works properly. A friend of mine put me onto a company called Klima Design Works that offer cooling system upgrades for W123 and W126 cars. They have a monovalve elimination kit for sale. Their kit is focused more at the W123, but can be adapted to the W126 as well. 
The kit uses a vacuum solenoid to turn off the coolant flow instead of the electromagnetic monovalve. I especially like that the valve is closed if something goes wrong. Here in Australia it gets very hot, and A/C is used far more than heat. The W126 system is a bit more complex than on a W123. For starters, the heating components are behind the first firewall and the heater core has two outputs that go into the monovalve instead of one. Klima Design Works suggest leaving the W123 monovalve in place and putting their heater valve upstream of the monovalve. They do suggest removing some of the components to increase flow. 
The picture above shows the coolant flow for the heater. Its not 100% correct as this picture shows the duo valve for the manual climate control, but other than that, its the same. The coolant enters the heater core via hose 68, and exits through hoses 50 and 53 where it enters the monovalve. The monovalve controls the flow of coolant. There is an auxiliary water pump (26) that helps flow coolant at idle to generate more heat. 
The hoses are exposed when one of the control boxes (that sits in the metal frame) is removed. The monovalve is on the left, hoses in the centre and the auxiliary water pump underneath. The simplest way to install the kit would be to cut the hose on the engine side of the auxiliary firewall (hose 68) and install the heater valve there. That seems like a bit of a hack job to me. I want to keep the components on the other side of the firewall as the factory did. The advantage of leaving the monovalve in place is that the car will look more original. Having said that, removing it can easily be reversed, and I am planning to remove it and the auxiliary water pump. The auxiliary water pump is only necessary in very cold climates, and it is one more thing to leak and cause problems. On the Series 1 cars it can cause major problems as it is unfused. Best case it takes out the climate control unit. Worst case it causes a small fire. The Series 2 cars don’t suffer from that problem and disable it if too much current is drawn. I am thinking of combining hoses 50 and 53 with a T-piece. I would then mount the heater valve on this combined hose and join it to hose 59. This would be the simplest solution. The heater valve would sit where the auxiliary water pump used to be and the solenoid would sit where the monovalve used to be. Other than cutting hoses (which are consumables) I won’t be permanently modifying the car in any way. 
The picture above shows the removed monovalve, auxiliary water pump and various bracketry. It is a very fiddly job removing all this stuff is there is very little room to work between the two firewalls. Still, with these components removed there is now plenty of room for the new heater valve and solenoid. The picture below shows an elbow piece as an example of how the hoses will flow. 
Removing all these hoses is a good opportunity to clean out the leaves that have accumulated underneath the hoses. I’ve also removed the cowl coverings to give things a good clean in there. It was necessary to remove the control box bracketry. I’m a member of a few different car clubs (Mercedes, Jaguar, Citroen), but am rarely able to make events. With a young family the times rarely work for me. A lot of the time I spend either working on or driving my cars is late at night. I figured I am not the only one in this situation, so after a poll of a few friends from the Mercedes club, we have started up a monthly night drive. Not only is driving at night more convenient for me, but the traffic is greatly reduced, especially cyclists. Obviously you have to be more aware, particularly of wildlife. Many petrol stations are closed too. The first one was in late July and the route was up the old Pacific Highway to the outskirts of Gosford. 
On that inaugural drive, we had a 380SEC, a 420SEL, my 450SLC and a 280CE. The old pacific highway is quite a twisty road and is a lot of fun even at the legal speed limit. It was also a good run for the 420SLC with its new injectors. That drive was pretty uneventful and we came back via the motorway. This months night drive was around the back-roads between Dural and Wisemans Ferry. That route is not as demanding as the Old Pacific Highway, so it was a good night to take my 250SE Cabriolet.  The weather was almost warm enough for top down motoring with the heater on, gloves and a hat. On that drive we had a 280SE 3.5 (above) and a W211 E55 AMG, Audi S3 and CLA250.
This months was also a lot of fun, but perhaps a bit more eventful. At the final meeting point we disturbed an amorous couple in a Ute who had to quickly get their clothes on and drive angrily away. Secondly, on the drive back the charging light on my 250SE started to flicker on and got brighter and brighter on the way home. After a while, I turned off the radio, but figured headlights were pretty important. Luckily for me it was failing slowly so I was able to drive home without incident. When I arrived back, I tested the voltages with a multi-meter. With the engine running and headlights on I had only 11.6 volts at the battery. With the engine and headlights off, I had 12.2. Thankfully the 250SE does not have any sensitive ECUs etc that would not have enjoyed running with low voltage. A couple of months back, I noticed a bad fuel smell from my E-Type. I was able to trace the problem to a leaking E-Type fuel pump. The car still had the original points type SU pump, which are rebuildable. After speaking to a few people, and doing some research, I decided to purchase a new pump. The new SU pumps are a solid state version, so no points inside. I’ll keep the original pump with the car in case I ever sell it and somebody wants the original. 
As can be seen from the picture above, the new pump looks pretty much identical to the old one. It is a relatively simple matter of moving the mounting brackets from the old pump to the new. The photo below shows the brackets on the old pump before I transferred them. 
I later learned that it is much easier if you just slip on the circular bracket without tightening it up, to locate where along the fuel pump it should sit. I didn’t have it quite right and I had to undo it to properly locate the bracket. These brackets are what turn the generic SU pump as used in countless British cars to the E-Type fuel pump. While replacing the pump, I also replaced two of the rubber isolators. The were the two for the circular bracket. The rubber isolators stop vibrations from the pump transmitting to the car. In the parts diagram there are supposed to be three, but the front one on my car was different – It was being used as a ground connection and there was a small rubber donut that was still in good shape. On the other hand, the other two were in poor shape with one completely broken. 
Getting to the furthest one can be a bit of a pain. The new isolators were actually a bit easier to fit as they had hex top and bottoms to make tightening up easier. Once the isolators were in place, I was able to locate the circular bracket, tighten it up and then mount the pump to the car. I sanded the washers to ensure they were really clean and then its quite simple to attach the fuel hoses to the E-Type fuel pump. While I was attaching them, I noticed some very small cracks starting to appear on the outside of the hoses. They do not leak, but before I put all the trim back in the car, I will order some new hoses and replace them. 
A few quick tests showed no leaks. Firstly when turning on the ignition and priming the pump. Then while starting the car and letting it idle. Finally driving for 10 mins and pulling over to check for any fuel. All good. Surprising the new E-Type fuel pump has impacted the driving experience. The car has better throttle response if you accelerate in top or third gear. Before it felt like it was pinging, but actually the old pump might have been starving the car of fuel? In any case the car is better and I was able to re-advance the timing a bit on the small adjustment wheel on the distributor. The engine is still not as smooth as I would like. I notice the motor mounts look quite flat, so this is something to look at. It may also need a tune if the fuel pressure was off before. | |
