new member, merc 190 problems

[simonmc]

Hi, there all.
I have a few small problems with my ebay bargain 1886 190. I knew of several of the faults already and most of these will be solved by a good service. However the seems to be a leak in the vacuum system wich means the central locking, headlight adjust, and the vaccum gauge do not work. However the pump under seat seems to work. Also the tacho does not work. All of the faults are of a non critical nature but are annoying as i would like to get them working. I have already found several disconnected pipes and reconnected them.

Is the vacuum gauge electrical or mechanical? And how do you remove the instrument cluster?

Also are the small white/yellow cylinders one way valves? and if so do the come apart? (I work in a rubber gasket factory, so i may be able to replace any seals)

Thanks for any help

simonmc

 

[benzfan]

There are several things that use vacuum on a 190e, those you have mentioned as well as the ventilation flaps on the climate control. Do those work? If so, it is not likely a vacuum leak. A leak would cause a rough idle on a 190. If the vent flaps work, it is more likely that someone in the past had a leak, and just plugged the offending section of vacuum lines. The vacuum gauge is mechanical and has a line connecting at the rear of the cluster. The 190e has a vacuum resevoir behind the rear splash guard in the rhs wheel well (in Canada anyway - yours may be on the other side). There is a vacuum line that runs across the car behind the battery to supply this resevoir. If a previous owner had a battery leak or explode, this line will literally be eaten away. I have seen several that had that (again, I describe a Canadian model - I suspect yours is just a mirror image, with the vacuum lines starting on the drivers side near the brake booster, then crossing to the passengers side behind the battery, to the resevoir behind the splash panel). Check this line. Once you have determined the resevoir functionality, you can then start to move forward into the engine compartment checking all lines, then back into the passenger compartment checking lines. Look for plugged lines, disconnected lines and finally leaking individual components, but I suspect you will find a section plugged off. Don't be afraid to disconnect things with the engine running, to check for the presence of vacuum in that section.

Given that your tach does not work and your vacuum gauge does not work, I would pull the cluster first. This is easy if you remove the steering wheel. Don't forget to disconnect the speedo cable as you bring it out, as the cable will limit your pulling of the cluster. Be careful with the fibre optic connections for the console lighting. The cluster on the 190 is relatively fragile, and if someone has tampered with the odometer mileage or "serviced" the cluster, they may have messed up the reassembly by overtightening some of the screws that just thread into plastic. This breaks the plastic, and can affect the ground connection for the tach that is simply a flat strip of metal that relies on tight screws for its connection integrity and runs across the back of the cluster. I have seen this too on a car I bought many years ago. Crooked dealer. Make sure the hose to the back of the vacuum gauge is intact, and you can again run the car with it disconnected to confirm the presence of vacuum.

Vacuum problems are some of the most difficult to track down, but if you approach it logically like you would an electrical problem (i.e. section by section, starting at the source) you will find it in short order. Best of luck.

 

[simonmc]

Cheers for that info, not to sure about the heating controls as the car did not get warm much on the drive back yesterday from picking it up (75 miles). Found out this afternoon it had the center of the thermostat removed! I did notice that the drivers side vent did warm up a bit but the center ones did not seem too. Looks like i will have to slowly have diagnose the vacuum system as you said.
Also is it possible to get airlocks in the cooling system, and if so what is the recommended way to remove them as i want to flush out the cooling system as the water in the system looked a bit rusty?
P.S. i hope the odometer has not been fiddled with as it is on 197K.......

simonmc

 

[benzfan]

The centre vents should only open when the A/C is running, not the heater, so it looks like you probably have a disconnected or plugged section of vacuum system unless they were blowing cold air in which case the entire system may not be getting vacuum. You can test by selecting various combinations of outlets with the car running and seeing if the flaps do indeed move.
Air can be bled out of the heater by dialling the heat up full, and running the car up off idle for a bit. It doesn't take long. 197k is reasonable for an 86, but that doesn't mean it hasn't been fiddled. Through a lot of research, I found mine had a true mileage of over 400k miles and over 500k when I sold it and it was still a solid car. I did replace things like bushings and bearings. The 190 will last a long time and is easy to work on. I recommend buying a copy of the Bosch fuel injection manual from Amazon or some such bookseller, which is extremely helpful in learning the KE Jetronic system and giving you the knowledge to troubleshoot. MB also had a CD manual which is a very good investment if you are planning to keep the car a while.

 

[simonmc]

Thanks again for the info. My car is only a base spec 190 so it does not have air con or fuel injection. However any info can only incease my knowledge base. I have the last few mot certificates and it seems the milage could correct.

I think a systemactic elimination of the vacuum systems is in order. As a quick test on things like the headlamp adjust, would sucking on the vacuum pipes to each part work to eliminate them as faulty, or would i need a stronger vacuum?

Also i read somewhere that there are perisable seals/diaphams in the actators for the central locking. Are these items expensive?

By the vacuum pump under the rear seat i found another connector near the pump that did not seem to go anywhere. Should there be another unit next to the pump that i'm missing?

 

[Geoff_Slade]

If the 190 heating system is like the W124 E class then the centre vents only blow cold air (or with a/c they blow very cold air!). Strange at first when all other manufacturers have centre vents that blow heated or unheated air but I suppose that's the thing about MB they are different to all other manufacturers and have their little idiosyncracies that you eventually get to know and love. Sorry can't help with the rest of your queries.

 

[benzfan]

If you are getting vacuum at individual components and they are not working, you need to purchase a vacuum tester, which is just a gauge mounted to a squeeze handle with a test port and is not expensive. It will draw and hold vacuum on individual devices so you can see if the vacuum is holding and the device operating. If the vacuum does not hold and the connection to the tester is not leaking, the actuator you are testing is faulty.

 

[simonmc]

Hi, again. I have got the vacuum gauge and the headlamps working, and there does not seem to be any other leaks. I found that the pipe to the vacuum gauge had come away. However i could not find any fixings holding the instrument cluster in, only a friction clamps i could see from underneath. Where are the fixings or does the instrument cluster just pull out? I managed to get the pipe to the vacuum gauge back in from underneath which was very tricky but i still need to pull the cluster to investigate the tacho problem, as the fuse feeding keeps blowing and thats stopping me fixing the cooling system properly :-?

 

[benzfan]

The cluster should just pull out (partially until you get the speedo cable disconnected). Sometimes it's easiest to reach up under and push from behind, if your hands are small enough. This should dislodge it.

 

[squealinneil]

simonmc,
There's a 190 only site at http://www.mercedes190.com/
Together with the wealth of info available from the knowledgeable on this site you should be able to dismantle that thing & put it back together in a weekend!
How much was your ebay 190 carb?

 

[simonmc]

My 'Bargain' cost a whopping £132 from ebay. So far has only needed a bit of work to get it run better ( the run back form dorset helped as it had been stood a while) and a good service/tune should sort out the slight hesitation i get when i accelerate. There is a couple of small cosmetic bits on the body that need sorting out, but i am waiting for better weather.

Overall i am very plaesed with it, and starts very well in the morning. This is the most important thing for me as i work nights and being in the carpark at 6 oclock with a car that wont start is not fun.

It still has 5 months MOT left. All the minor faults on it that i have sorted out have not cost me nothing but time, and have given me great statisfaction. Also the better half loves it and she does not mind IF i have to spend a few quid on it. It is by far the best impulse buy i have ever made. Much better than the vauxhall it replaced.

 

[squealinneil]

They're great cars. I have 3 at the mo. a 2.0, a 2.6 & a 2.5-16 (you can tell I like them). They were over engineered & over built beacause it was MBs 1st venture into the small car market & they had to get it right. There are zillions of them still on the road with D, E, F & G registrations. You don't see hardly any Fords, Vauxhalls, Rovers etc from the same era. They don't build the new models nearly as well. None of the 190s I've had have ever had any rust either - none.
Hope your car keeps going for you, but if something goes wrong at £132 it doesn't owe you a penny.

 

[simonmc]

I agree its a great car. I have found a website that has online manuals http://mb.braingears.com/
Well usefull.

 

[Neophyte]

Vacuum?

Guys, I've got a 190e '92 2.6 auto. Does this vacuum thing - what is it? does it power components in my car? what does it look like? am real confused!

thanks!