Brakes!

After a lot of fussing the car finally has brakes! But before that happy result, there were a lot of little problems - leaks. At one point, a few weeks ago, we had the brake system all put back together and were in the process of bleeding the wheel cylinders. I was in the car. The car was up on the lift, and my helper/advisor was below doing the bleeding. I started to feel some pedal, finally, and just when I was starting to think that we were just moments away from having the brakes working, a leak occurred at the left rear wheel cylinder. Bummer.

We decided that I needed to buy a whole new set of copper crush washers and probably replace all of them. Since we were unable to continue working on the brakes we decided to start the car up and check out the carburetors. The engine started fine but shortly after starting, a lot of white smoke was coming out of the exhaust pipe. My first thought was that my rebuild of the brake booster failed and we were getting brake fluid sucked into the carbs. I disconnected the brake booster and plugged the vacuum hose to see if that helped. No. Still a lot of smoke.

Then we took the air log off of the carburetors so we could see better what is going on. Gasoline was pouring out of the carb throats and onto the exhaust manifold and we had a very short but scary fire in the engine compartment. Fortunately it was put out really quickly and no damage was done.

What we thought was going to be a good day, getting the brakes working, turned into a bad day very quickly.

The next time I went to town to work on the car I had crush washers, new gaskets for the carb float bowls and new bleeder screws. We replaced all the washers at the wheel cylinders and tested the brakes. Another leak! This time at the front left wheel. We took off the brake lines and discovered that the spot on the wheel cylinder where the line goes in was badly scored. We had to take the wheel cylinder out of the wheel, which meant taking the whole brake assembly apart. I ground the back of the wheel cylinder flat to take out the groove in it and put it back together. Finally no leaks. We got brakes working! Yay! Then I discovered a small leak at the brake booster.

The brake booster

We moved next to the carburetors. I took the float bowl covers off and removed the float valve assemblies. the valve was stuck. After soaking them in carb cleaner they moved freely and we put it all back together and fired up the engine. This time it took quite awhile before some gas started barely seeping out of the carburetor throats. There is a lot less smoke coming out of the exhaust, too. Progress is being made at least. There is still too much gas going in. We tried adjusting the mixture but that's not the problem. I need to soak the float valves some more to see if that helps. I also am going to hook up the diaphragm fuel pump to see if that is better. The idea is that the electric fuel pump is pushing just a little too much pressure for the float valve to stay shut. It's a low pressure fuel pump but maybe not low enough pressure.

While running the engine I thought I would check the charging voltage. Not charging. The generator is not generating or the voltage regulator is not regulating. Something wrong anyway. I looked down in there and could see that the wires to the voltage regulator look pretty bad. Maybe something is unhooked. We ran the engine for about 20 minutes until it got up to temperature. The cooling system seems to be good. It steadied out at about 170 degrees. We turned off the engine and then I noticed a leak in the cooling system. There is a fitting coming out of the middle of the cylinder head and there was a leak at the hose. I took the hose off and the fitting is mostly rusted away. I managed to push the hose on far enough to get it to seal so it's OK for now. Eventually I will have to replace the steel tube.

The day was over, though, and no more time to work on stuff. We got everything done that needs to be done from underneath the car so I figured I could finish working on the carburetors and fix the electrical problems at home since that can be done from above.

The next day I brought my trailer to town, loaded up the car and took it home. It is now safely back in its garage. Only now it has brakes! I figure half a day's work on the carbs might get them sorted out. Then generator charging issue is an unknown. the small brake fluid leak at the brake booster should be fixed by replacing the crush washers. I remember re-using the old ones at that spot when I put it together.

I am another step closer to driving the car, at least around our yard.

Nita ready to steer as I push it into its garage.

Further Down the Rabbit Hole

October, 1955 issue

I am deep into mechanical work on the car now and I haven't been taking many photos. This is for three reasons. 1. I am too busy working on it to remember to take pictures of the process, 2. My hands are too greasy to want to touch the camera, and 3. Any photos would be of engine and brake parts and probably not all that interesting to look at. So, because a blog post is always more entertaining if there are pictures in it, I am including vintage 190SL photos that I found on the web.

You never know how much trouble you are in for when resurrecting an old car. I got a new brake master cylinder but it is not exactly the same as the old one. The exact one is not available, apparently. Here is the possibly boring story.

1955 was the first year of 190SL production. That first year did not have a brake booster so the master cylinder was designed to work without one. In 1956, the year of our car, they started using brake boosters and a different master cylinder. For two years, 1956 and 1957, the brake light switch, which operates on brake fluid pressure, was attached to the end of the master cylinder. In 1958 they moved the brake light switch to the brake booster. The hole in the master cylinder where the switch used to go is now sealed off. The only master cylinders available now are designed for 1958 and newer cars. So we have to find somewhere else to put the switch.

To do this so that it matches the way Mercedes designed it requires the purchase of more parts. There is a "Y" fitting that costs $45. But this fitting is pretty thick so I would have to buy the hollow bolt that mounts it ($28). Then I would have to get a different switch because the mounting holes are different sizes. I can't even find that part.

What I think we will do is just put a generic pressure switch in the brake line that goes between the master cylinder and the brake booster. This will work fine even though it is not the way the car was originally put together.

A rendering from the 1957 190SL dealer catalog

The carburetors are another rabbit hole I am falling down and don't know how far it will go. This car has its original Solex carbs. I am SO glad I have these! To buy new ones would cost an unbelievably huge amount of money. Fortunately I don't have to buy new ones. The ones I have are leaking from the bottom though. Perhaps it's just a couple of gaskets?

I checked a diagram of the carb. It is not a couple of gaskets. What is leaking are the accelerator pump diaphragms. Maybe the cover plates just need to be tightened. I will try that next time I work on the car. If  the diaphragms are bad they will have to be replaced. A pair of new ones costs $320. Ouch!

I am missing all except one of the gaskets for where the air intake plenum (190SL folks call it an air log) attaches to the carburetors. They are paper gaskets and aren't that expensive but even cheaper is to make them myself using gasket material. That's what I will do. I will use the one that I have as a template and cut three more and it should be good.

On the assembly line in February, 1958

There are two carburetors linked together on this engine. The fuel lines are a bit complex. The one that connects to the rear carb needs to be replaced. Unfortunately I cannot just buy that piece. I would have to buy the whole assembly which is $350. I think we will try to make just the piece we need and not replace the whole assembly.

When looking closer at the carbs we noticed paper stuck in two of the ball and cup linkage fittings. This must have been because they were popping out due to wear in the fittings. I am sure the paper won't last long so I will have to order some new ones. Fortunately these are not expensive.

We pressure-washed the underside of the car this afternoon. There was a lot of oil, grease and dirt under there. We got it mostly clean and then put it up on the lift to inspect it all. There are about 30 grease fittings!  Every moving part of the front and rear suspension had one or two fittings. We greased them all so they should now be good.

Not everything is bad news on the way down the rabbit hole. We discovered that the center link tie rod was loose and, fortunately, it was just a big nut that needed tightening. A super easy fix. We discovered that the differential is not leaking gear oil. What we thought was gear oil was just old grease that had broken down. We also inspected a rubber boot that often goes bad on the rear swing axle. It turns out that it was replaced with a new one back when the car was being worked on in the early 80's. It is in perfect shape.

This truck is awesome!

The drain plug on the oil pan is all rounded off so I am going to order a new one. Lucky for me it is inexpensive and not hard to get. The valve cover gasket also needs replacing. It's not super cheap but it's not expensive either. Only about $30.

I have been working on this car for about a year and a half now in my spare time. It is starting to feel sometimes like it will never get done. There is so much left to do! But every time I work on it some small bit of progress is made so I suppose, at some point, I will actually get in the car, start it up, and drive around. Between now and then, though, I am sure there will be plenty more discoveries both pleasant and unpleasant.

Will the accelerator pump diaphragms need replacing? Will we get a brake light switch to fit the way we want it to? Will I be able to successfully get the brake booster back together? Will the brakes even work when the whole system is fully assembled? Stay tuned!

This pic is from the 1957 dealer catalog

The Big Push

Last Tuesday I loaded the car on my trailer for a trip to a friend's auto repair shop. He has lifts and a huge selection of tools as well as people who are used to working on cars all the time, unlike me who is a dabbler. The plan was to install all the new brake parts, fix or repair other brake parts, and get a look at the underside of the car to see what else it needs.

I had a helper, but really I was his helper. Nick has been working on cars his whole adult life and has the skill and confidence that I don't have. I always get frustrated when something doesn't come apart easily and I often end up breaking things. He knew just how to get stuck things unstuck.

We got it up on the lift and started working. The first project was to remove the brake master cylinder which is in a spot that would be extremely difficult to get to if the car was on the ground or even up on jack stands. Up on the lift, it was much easier but still a challenge. Nick worked on this while I took the wheels and hubs off and got all the brake parts for the wheels ready to install.

We spent all day working on the car and got the master cylinder removed, the front brakes done and one of the rear brakes. I repacked the front wheel bearings, too. The master cylinder was pitted, as I suspected, so I ordered a new one. It should be here tomorrow. I thought about sending the old one to be re-sleeved but that would take a couple of weeks. The new one will get here sooner.

Nick discovered that the center link tie rod needed to be replaced. Fortunately I have one that was bought for the car 30 years ago and never put on. Also the oil pan and differential leak so we will try to do something about that while the car is there.

The first wheel cylinder gets installed

The next day I couldn't go to town to work on the car but Nick finished putting the wheel cylinders in and fixed a steel brake line that I messed up when I was taking the brakes out of the car. So great that he can do this!

Thursday was another day in town for me. All of the bays at the shop were in use so we couldn't put the car up. I spent an hour or two trying to get the brake booster out of the car. Some of the mounting bolts were rusted and it is not an easy thing to remove anyway. Part of the process means lying under the dashboard. I am a big guy and it's a small car. I was pretty crammed in there but got it out. The plan was to take the brake booster home and disassemble it to see what it needs.

I did that today. It was a challenge. The case was stuck shut by rust and gunk. I eventually got it apart, though, and cleaned all the parts I could get apart. Most of it looked really good once it was cleaned. There are a couple of rubber gaskets that need to be replaced for sure. The power piston is the biggest one and it is designed to move air, not brake fluid. The gasket on it is made of leather! Fortunately it's in good shape.

brake booster mostly taken apart

The brake booster uses the engine vacuum to assist in pushing brake fluid to the wheels. It's a complicated piece of equipment. I hope I can get it to work without too much expense. Buying a new one is out of the question. New ones cost almost $2000! If I need to get a rebuild kit I will have to spend just under $300. It is possible that I can find generic replacements for the rubber washers that I know are in bad shape. We will see how it goes.

Next week I will be back at the shop installing the new master cylinder, replacing the tie rod, and fixing the leaks in the oil pan and differential. It will take longer to get the brake booster done. If I am too excited to drive it we might bypass the brake booster. The car doesn't weigh much so not having power brakes should not be too big a deal.

My hope, before I started this big push, was that the car would be marginally drivable by this Thursday, which is my birthday. I am beginning to doubt that we can get it together in time but maybe?

Documentation Exploration

I found out through the 190SL Group forum that you can send away to Germany for a copy of the original build sheet for any Mercedes. All you need is the VIN number. So I sent our VIN to the Mercedes Benz Classic Center and the guy there sent it to Germany. A few days later I got a digital copy of the build sheet. There was a problem, though.

Everything is in German and the copy is quite faded and distorted. Remember that this piece of paper was almost 60 years old! Anyway, from what I could determine, this build sheet was for another car, not ours! It said that the car with this VIN number was a coupe, not a roadster, and that it was originally metallic gray with red upholstery. Ours should have been red paint with black upholstery. Definitely not our car. So I had to do more research.

wrong car!

It turns out there are three numbers associated with these cars. There is the chassis number, the body number and the engine number. Most of the time the chassis number became the VIN. On our car the body number was selected to be the VIN. I don't know why or how rare this is or if it is a problem. The car has been in our family since 1975. Probably not a problem.

Chassis number plate on firewall behind the battery

With 190SL's the whole "numbers matching" thing doesn't apply. With 190SL's the three numbers almost never matched, not even the very first cars. I read that. on the first two 190SL's made, the car with chassis number 5500001 had body number 5500002 and the chassis number 5500002 had body number 5500001. It really didn't matter to the guys at the manufacturing plant. Our car has a new engine in it so that number definitely will not match what was originally put in the car.

Body number plate on driver's side door jamb.

Our car's body number is 6502520 and the chassis number is 6503849. The first two digits depict the year it was made, in reverse. So the 65 means that it was made in 1956. The next five digits are the production number. In 1956 they built 4032 cars. Ours was number 3849 of that production year which would indicate it was made late in the year. The official production numbers from Mercedes aren't completely correct, though. Here's a link to a page that describes the production over the years and how Mercedes sort of fudged the numbers.

190SL's were hand built. Each body part has the body number on it, at least the last four digits of the body number. Only number-matched body parts fit together properly. On our car you can find the number 2520 stamped or written on the body parts. I even found it in chalk on the inside of the back of the driver's seat.

There is another chassis number plate mounted to the frame of the car. Above the plate, the same number is stamped into the frame below the voltage regulator. It is facing up so it can be really filthy with oil and dirt. I scrubbed ours off but you can barely make it out. Not an easy place to get to either. I couldn't read it at all just by looking at it. I had to use a flashlight and stuff my camera down there, take a picture, and blow it up in order to see that it is the same number as the plate behind the battery.

An unusual thing about 190SL's is the year the car was built is often not the year shown on the title. The cars were registered the year they were sold, not the year they were built. So our car is registered as a 1958 but it was built in 1956. I figure that it probably doesn't really matter as far as the legal stuff goes but it is important to know the year it was made to get the right parts.

When I registered it here in AZ, I didn't bother to try to change anything. I suspected that might turn into a bureaucratic nightmare. Still, it would be cool if, someday, I could get the title changed to show the year of manufacture and to have the chassis number be the VIN like most of the other cars out there. Or maybe it doesn't matter at all.

Now I have to bother the Classic Center again with a new number (the chassis number) and ask them to send to Germany for the build sheet that actually belongs to this car.

I will end this post with something much prettier than these dirty number plates and faded documents. I found a model of our car in a thrift store for $15. Cool, huh?

Lots of Little Details

One of the things I was dreading having to pay for was a headlight trim ring. The car came with only one and that was original with the car. It says Bosch on top of it. New ones are available but they don't have anything engraved on them and they cost $600 each. So, in order to have a matching set I would have to buy a pair or hope to find someone selling a used one that matches my other one.

There are two styles of headlight rings. The European style has a larger opening than the ones made for cars that would be sold in the U.S. After about a year of regularly searching eBay I found a ring for $65 and, because it was so inexpensive, I took the chance and bought it. That's when I discovered the details of the difference between Euro and U.S. trim rings. It was Euro. Wrong for this car.

I kept searching and finally found a correct, original U.S. trim ring on eBay. I made an offer, the offer was accepted, and I got a used headlight trim ring with the correct Bosch engraving on it for $300. It was in nearly perfect condition, too. So cool!

I got the re-sleeved brake cylinders back and have ordered and received the new steel brake line that I messed up. I really need to try to get the master cylinder out of the car but it is so hard to get to that I will take it to a shop in town with a lift. I am waiting for the shop to be ready for me. Another brake part I am a little nervous about getting into is the brake booster. This is a complicated bit of machinery that uses engine vacuum to boost braking. Fortunately I can bypass it until I am ready to tear into it.

I was missing the little arm that holds the hood open. After some research I realized that this hood support was just a piece of steel flat bar with a notch in it. I made one and installed it on the car. It worked great. Later, when I was looking through a box of parts, I found the original one. So I took off my home-made one and installed the correct one. So much better than holding the hood up with a board wedged in there.

I ordered and received the two missing parts from the horn ring assembly and put those in yesterday. I haven't tested it yet. While I was in an electrical mood I took some time and removed all the fuses from the fuse box and cleaned all the connections which had corroded over the years. It is good to have this done so I know that at least the fuse box won't be the problem when I get around to getting the lights working...... I hope.

I spent some time working on the doors. I found the clips that hold the fuzzy strips in place and installed them on the driver's side door. The window goes up and down between these strips. I cleaned and lubricated the window regulator mechanisms on both doors. There are a couple of missing bits before I can put the windows in. There are guide blocks that go on the front and back of the door glass. I have three of them and am missing one. I also need some thin felt strips for where the window gets bolted onto the channel that goes up and down. Once I get these things I will have windows that go up and down.

Last week I got the missing passenger-side metal false floor piece. It didn't fit. I had to trim it. This is because there are old sheet metal patches in the floor of the car that take up more space than the original floor panels did. Once I got it to fit I painted it black and installed it. Now the floors of the car are all ready for carpeting. I am not ready to order the carpet just yet. A carpet set for this car will cost about $650. That's pretty steep but I want to get the right stuff - German square weave. Not sure what color to get. I have been looking at photos of other people's 190SL's to see what they have done. The two most obvious choices are caramel or red. The upholstery is a caramel color - officially called dark tan. Most of the red cars with dark tan upholstery I have seen have dark tan carpet. But red might look cool, too. It would also show dirt a bit less than the dark tan.

There are some chrome trim bits in a box that I haven't been able to figure out where they go. Well, yesterday I figured it out. they go on the posts on either side of the windshield and they hold the rubber seals for when the windows are up. I spent some time cleaning them up. Also in the box was a bunch of weather stripping that was purchased for the car 30 years ago. I wasn't sure where it all went but now I know. Another mystery solved.

I started messing with the sun visors and with figuring out which little chrome piece is the center hold down for the convertible top. I am missing most of the screws for these so I will have to get new ones. The sun visors have green plexiglass in them. They are not in too bad shape but I also have brand new plexi if I decided to replace the original ones. Before I do that I think I will try some CD scratch cleaner on the old ones. Maybe that will clean them up enough that I won't have to go through the trouble of taking apart the frames on the visors.


It's slow progress getting this car together but it is happening. I read about a guy who was almost finished putting his car together and he had 900 hours in it already. I just need to keep plugging away at it.

Solving the Mysteries

Lights

 

I have redoubled my efforts to work on the car in the last few weeks. As it gets closer to being drivable I am getting excited. One of the big projects is to get all the lights working. I installed the front turn signal assemblies, which was fairly easy. Only one screw was stuck and I had to drill it out. In order for the turn signals to work, though, I have to install the horn ring which happens to also be the turn signal switch. You turn the horn ring left or right to turn the signals on. This was a strange design that they abandoned a couple of years after our car was built in favor of mounting the turn signal switch on the column instead, like most cars these days.

The order of parts in the horn ring

Because the turn signal controls and the horn are on the horn ring there are five wires hanging out of the center of the steering column. The horn ring assembly is complicated and I was scared of it and was wondering if I should just have someone who know what they are doing put it together for me. I decided to give it a go, myself. After sitting there staring at the parts for a couple of hours I pretty much figured out how it goes together, mostly. There were still some mysteries, though.

How the wires attach.

Fortunately I am a member of the 190SL Group, a club for owners. On their web site is a forum that is extremely helpful. I managed to find a photo of where the wires are supposed to attach and the order in which the parts of the horn ring are supposed to go together. I found out that I am missing a big rubber washer. According to a friend who restores vintage Mercedes, if I were to put it together without this washer I would get shocked when I touched the steering wheel! So I better order that washer.

I got bulbs for the front and rear turn signals in the meantime and installed them in the front but the rear is another mystery. The bulbs don't seem to be the right ones although the technical manual says to use the bulbs I got. I need to ask my friend what the deal is with that.

This car is being restored by my friend

Speaking of my friend, he recently got in a 1962 or 1963 190SL to restore for a client. He has it completely taken apart and the paint stripped off. All the parts are on shelves next to the car. This is great because I can check in with him every once in awhile, as he restores the car, to see how things go together. I am so lucky to have this opportunity. There can't be that many people specializing in restoring old Mercedes. What luck there is someone right nearby!


 

False Floors

 

Template for right rear false floor

Missing on our car are the wood false floor pieces that go in front of and behind the seats. The car being restored has them so I made templates from these so I can cut my own out of plywood. They are more complex than I hoped. The front ones are easy. The rear ones have other wood strips and some metal bits on them. There are two pieces for the rear. The larger piece, which goes behind the passenger seat is screwed on. The smaller piece is meant to be a "door" to a  compartment underneath.

The rear false floor sections cut from plywood

Using the templates I made, I cut and sanded four pieces of plywood. I just tested some black paint on them and it seems to work. The plywood needs to be sealed against moisture and it needs to be black, too. I will be using a primer-less spray paint meant for outdoor use. It should work fine. The pieces shown at left are for the rear floor.

Door Locks

 

A couple of months ago I took the front door handles to a locksmith. I don't have a key for them and I want them to work. They sat at the locksmith's for about a month. They said they couldn't find key blanks and gave them back to me. This weekend, with the help of the 190SL Group forum, I figured out how to get the cylinders out of the locks and managed to find a key that fit. It fit but it wouldn't turn.

With the locks apart I was able to file down the pins so that the locks now work. Well, not quite. There are two springs missing. They cost $50 each  but I think I can find generic springs that will work. We will see.

Down inside here is the retaining washer I made

One of the locks was missing a locking ring that keeps the cylinder assembly from spinning around and from falling right out of the door handle. I looked up getting a new one of these and this little ring, only an inch in diameter, is $90! I made one instead. I took an old washer that had approximately the right outside diameter and used a Dremel tool and a die grinder to make a new one. It worked!

License Plate Mount

 

The holes in the rear of the car are spaced for European license plates which are longer than U.S. ones. The mounting holes don't line up. I fabricated a bracket that will allow me to mount my license plate. Yes, I now have a license plate. I finally registered the car. I guess I am getting optimistic that the car will be on the road soon.

Brakes

 

The brake cylinders are in California now being re-sleeved. They are at R. Karp Sleeving in Upland. CA. He is putting stainless steel sleeves in them which will make them better than new since stainless steel is less susceptible to pitting. I should be getting them back in a week or so.

I still need to order some steel brake line parts and the brake booster probably doesn't work so I will have to take that apart and see if I can fix it. It will probably take me a full day to get the brakes back together once I get the wheel cylinders back from the sleeving place. When the brakes work I will be able to drive it around our yard! I will have to get the lights working before I take it on the road though.

Taking the Brakes Apart

Brake parts - the front brakes are in the box on the left.

Since the car had been sitting for over 30 years, the brakes did not work at all. This weekend was the start of the process of getting the brakes working - dis-assembly.

The front wheels are the most complicated. There are two cylinders at each wheel. I managed to get them completely disassembled in one fairly long day. The first wheel took the longest since I had to figure out how to do it. The second wheel went a lot faster.

I also needed to remove the rubber brake lines which had swelled closed over the years. This was the biggest problem. The nuts that held these lines on were stuck and took a lot of force to get undone. One wrench had to be on the inside of the engine compartment and another wrench had to be on the wheel side. Nita helped with this and the driver's side line came apart ok.

The air log is the big thing at the top of the picture.

Removing the rubber line from the passenger side was hard. The only way I could get a wrench on the nut inside the engine compartment was to remove the air log. This is a big aluminum tube thing that collects the air from the air cleaner and distributes it to the two carburetors. It took awhile to get the eight nuts and screws that held it on. Then I could get to the brake line nut. It was stuck and, in trying to get it loose, I broke the steel brake line. Oops! Now I have to get another one which will cost about $60.

While the air log was off, I was able to fix a leak in the fuel system. One of the nut that held a fuel line onto a carburetor was loose and I couldn't get to it with the air log in the way. Another problem fixed!

Once the front brakes were out I spent an hour or so cleaning all the parts. I couldn't get the pistons out of the wheel cylinders. It was getting dark so I gave up on that. Later that evening I looked up how to remove stuck pistons and got some good advice.

This morning the plan was to take the rear brakes off. This went really smoothly. The rear brakes only have one cylinder per wheel so there are a fewer parts. The rubber brake lines were stuck but, this time, I just cut them with a knife to make them easier to remove. I should have done this with the front wheels but didn't think of it. It turns out that the rear right wheel cylinder was new. It must have been installed when the restoration process stopped 30 years ago. I will still have to take it apart to see what the inside looks like. It could be ruined by rust after sitting so long.

One of the front wheel cylinders

The next project was to try getting the stuck pistons out of the front wheel cylinders. First I tried compressed air. I put the cylinder in a vise and held a cardboard box in front of the opening in the cylinder. I fired up the compressor and shot 90-psi air into the opened bleeder valve and the piston popped right out into the box. Perfect! It worked the same way on the next cylinder.

Compressed air didn't work on the last two cylinders. I used a grease gun instead. The end of the grease gun hose was the same thread and diameter as the hole in the cylinder so I threaded it in and pumped the handle. The piston slowly moved forward until it plopped out into my hand. I only had enough grease to do one of the wheel cylinders.

The problem with the grease gun method is you have to get all the grease out of the cylinders. Grease is not compatible with brake fluid.To do this I scraped out as much grease as I could using my finger. I used a rag to get more grease out and dropped the cylinder into a can of parts wash. Finally I sprayed carburetor cleaner through every hole and wiped it down with a clean cloth. That should be good enough.

With the pistons out of the cylinders I could inspect the bores. They were all pitted and ridged too much to get away with simply honing them. Bummer. What I think I will do is send them out to a place that puts stainless steel sleeves in them. This will be better in the long run since the stainless won't be susceptible to rust pitting.

I also need to order some parts. I need one of the steel brake lines and I really should get a master cylinder rebuild kit. I didn't take that apart yet. It is not easy to get to. I think, for the rest of this project, I will bring the car to a shop in town so we can put it up on a lift. That will make re-assembly a lot easier.

The front brake shoes look new.

My brother, Randy, found a couple of boxes of Mercedes parts at his place and sent them to me. Inside were several wheel cylinder rebuild kits and one complete rear wheel cylinder. Cool! This will save me some money. I also discovered that the brake shoes are good and the front ones are new. Nice! I hope that, when I get the front cylinders sleeved, that the rebuild kits are the right size. If so, I will be getting off easy.

I need to be able to roll the car around so I put the wheels back on, even though all the brake parts are out of it. It really rolls easy! Now I have to be careful to not push it into something. No brakes at all now, not even the emergency brake.

Top to Bottom

Another project is to get the convertible top put together. The frame was corroded and stiff and had the tatters of the old top hanging from it. I pulled most of it off and then started polishing the aluminum. With cleaning, polish, and lubrication it all works smoothly now. Some of the wood in the frame needs to be glued back together and I need to get some fabric to wrap some of the frame parts. I am not sure what to get, though. It looks like it had two layers - a thin black material first and a thicker caramel colored fabric on top of that. The straps that hold the stays in position also should be replaced.

Back in the early 80’s, when the car was being worked on, a new canvas top was purchased. When we got the car out of our mom’s garage in 2013, there was a stained cardboard box in the trunk. In this box was a new convertible top. It is still new, although it’s 30 years old. The fabric is fine so I will put this on the car once the frame is fully prepared.

I wanted to get the driver's seat in as soon as possible so I have something to sit on when pulling the car in or out of the barn. Before I did that, I wanted to patch all the holes in the floor and get it cleaned and sealed. There are several rust-through holes in the floor of the car. I started with the driver’s side first. Once I scraped a bunch of tar-like stuff off the floor, I discovered that it had been patched before. Two steel sheet metal panels were screwed onto what remained of the original floor and the tar was spread over it all to seal it.

It took me a couple of days but I managed to get it patched pretty well. On the smallest holes I used epoxy putty. On the larger holes I made sheet metal patches. The worst damage was right in front of the driver’s seat where the steel floor was about to fall through. I welded this back together and then used the epoxy putty to fill the remaining holes.

I cleaned it all with a wire brush and then sanded the whole floor with 100 grit sandpaper. The final step was to put two coats of POR-15 on the floor. It now looks pretty good, if I do say so myself, and it is sealed up, too. The passenger side is next to receive this treatment, then the trunk floor.

The seat rails were a little bent so the seats would not slide on them. I had to spend a couple of hours straightening the metal before I put the driver's seat in. Now the seat slides pretty smoothly. I need to put some sound-deadening insulation on the floor under the seat. The car originally came with jute insulation which explains why the floor rusts out on these cars. The jute absorbs water like a sponge and keeps the floor metal damp. I plan to get some synthetic insulation that will not hold water. I have a roll of jute that came with the car and I will use some of that in places where water won't settle.

When taking a long look at every part of the car, it is apparent that there is still a long way to go to get it drivable and even longer to get it looking good. Several of the knobs and dashboard bits are just hanging below by wires and cables. The windows are out of it and it looks like there may be missing bits from the window mechanism. No keys work in the locks. The ignition is the only place where the one key I have works. None of the lights work. Upholstery was started but is nowhere near finished. One seat is partly done and the inside door panels are mostly done. There are many more little things, too. Lots to do but I will get there and she will ride again!

No Stopping Now!

I was pretty sure that the brakes were not going to work. Even though the car had its brakes worked on before all work stopped on it thirty years ago, hydraulic brakes don’t hold up if left to sit. Brake fluid is hygroscopic, which means it absorbs water. That could mean that there was more water than fluid in the brake lines which would cause serious rust in the master and wheel cylinders. Still, there was no harm in adding fluid and seeing what happens.

The brake booster

I opened the brake fluid reservoir and loaded it up. My wife, Nita, was my brake pedal pusher as I worked my way through all the bleeder ports. There were two on the brake booster and, as Nita pushed on the pedal, clean brake fluid squirted out. Awesome! This meant the master cylinder wasn’t totally shot. It also meant that the brake booster might be in better shape than I feared.

My next task was to bleed the wheel cylinders. There are two cylinders on each of the front wheel and one cylinder on each of the back wheels. When I opened the bleeder port on the front wheels water poured out. Not good! Once the water was out, no amount of brake pumping produced fluid. Either the master cylinder was more screwed up than I originally thought or the soft brake lines were swollen shut. I suspect it’s the clogged brake lines.

I tried bleeding the rear brakes. Nothing happened. No water or fluid. For sure the front wheel cylinders will be pitted with rust, maybe too pitted to hone. The rear wheel cylinders are likely to be bad, too. The car will need a complete re-do of the brakes. The car will go, but it won’t stop, and stopping is kind of important! I went online and checked the cost of getting all new wheel cylinders, master cylinder, and soft brake lines and the cost totals up to about $1000 not including rebuilding the brake booster. That’s really not too terrible and it would be great to have all that stuff be brand new. I don’t want to be worrying about the brakes once I get it on the road. I have to save up for the brake parts so this part of the project will have to wait awhile. I can drive it without the brake booster so I can wait even longer to rebuild that.

In the meantime I discovered that the emergency brake works just fine. It’s a mechanical cable brake, as most e-brakes are, and it was in really good shape. So I can stop after all! I just have to remember to keep my hand on the e-brake handle at all times so I don't panic and try to use the brake pedal. I am only going to use this when I am pulling it out of the barn or putting it back. No driving on the road like this!

Up until this moment the 190SL was being kept in a friend’s garage. One of the conditions for bringing it home was that I could pull it in and out of the barn easily when the space was needed for other uses. With the e-brake working I figured that was good enough. I hitched up my trailer and brought the car home. It is much more convenient to work on it here. I can go out any time and put in an hour or two on it and since I got it home I really have been able to put more time into it. The other day I went out and polished the two hubcaps I already have and the trim rings. They aren't in perfect shape but they look a lot better than they did when I picked up the car. I need to keep an eye out for two more hubcaps.