... I hope you mean solar panels on the roof of your house...
I'm picturing solar panels on the MB charging some type of death ray... mmmmm
get a 13mm wrench and pull the MC from the booster, look in there and see if there is any fluid in there... if there is, your mastercylinder is leaking into the booster. and more likely than not you will need both a booster and a MC...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Hahahaha yes, solar panels for the house roof. However, at one point since these cars don't run off spark plugs and don't really have much electronics in general, I was thinking of mounting a panel either on the roof of the car or on the dash, and removing the alternator to gain power and HP. Thats another day..... maybe.....

Ill take off the MC to see if there is fluid in there. Not looking forward to buying both a new MC AND a booster

If I need a booster I will certainly be hitting you up vstech. I found some much lower priced as "refurbished" but still are not exactly cheap - if you have some to spare than I would love to buy one off you.

Ok, took the master cylinder off, and the booster is filled with fluid. I was able to get just about all of it out, but there was a LOT in there. I would say there was almost 2 bottles of brake fluid in there (12 ounce bottles) in the booster.

I assume this is probably causing the issue right?

How would I tell if that damaged the booster as well?

Also, I know there is brake fluid that got on/in the lines to the vacuum pump.... will this damage vacuum pump components, and if fit gets into the crankcase, will this damage anything?

Thanks

This would certainly cause poor braking. Go ahead and take it for a drive. If it got in., it would mix with the oil. Maybe eat seals? I wouldnt worry about as long as it was below the mbc itself as the vacn is drawn at the top.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Ok I got the new master cylinder installed, giving me the same problems. The brake booster holds vacuum until the brake pedal is pushed. Also, I noticed that if I let the engine run for a little bit, I can turn it off right away. If I hold the brake pedal down while I turn the car off, it takes it much longer to turn off.

Is there any possibility that this could be from poorly bled brakes? Would that let too much vacuum out when pushing the pedal down too far?

I am assuming its time for a new brake booster Is it possible to remove on a w116 without removing the MC again?

bump

I have always just assumed that the vacuum system needed a second or two to recharge the brake system after using all the available vacuum. Normal usage of the brake system, after all, rarely involves two vacuum-sucking emergency stops in rapid succession.

I can keep the car running indefinitely by pumping the brake pedal moderately with the switch off; it just consumes all the available vacuum and therefore doesn't let any of the other components get any.

I don't think you're experiencing a "loss of braking power" when this happens, I think you're just feeling what manual non-vacuum-assisted brakes feel like. I assumed they just didn't have enough vacuum pump to let you drain the entire system and re-vacuum it instantly. As long as it's back to full capacity within two or three seconds, I assumed it was perfectly normal.

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~Michael S.~
Past cars:

1986 300SDL
1987 300SDL
1982 240D
1982 300SD


Current:

1987 300SDL

I think you have started on the wrong end here. The problem is almost certainly your vac pump. Did you test it?

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

I have not been able to locate anything to test the vacuum with. The thing that makes me think its the booster is when I push the brakes it makes a swoshing sound like its sucking in a lot of air, and the vacuum holds fine till the brake is pressed.

Either way, I got the booster after seeing these posts, and the other one is already out. So I am going to install this new one (got it cheap, 50 bucks brand new from Checker Auto). After that, the only thing left is the pump.

then what happened?

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Aquilae non capunt muscas! (Eagles don't hunt flies!)


1979 300SD Black/Black MBtex239000mi
1983 300TD euro-NA. White/Olive Cloth-MBtex 201000mi. Fleet car of the USA embassy in Morocco
1983 240D Labrador Blue/Blue MBtex 161000mi

I think he replaced his booster.

Car still slow to shut off - vacuum questions

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91 350SD
14 F150 Eco
19 Fusion Hybrid
11 GT500

Well, I replaced my booster, and the car stops much better now. But still, if I push down on the brake several times over a period of a few seconds, I lose all power assist function, and have to push very hard to apply brakes. I got too busy with other projects and am just using it as is for now. I assume it needs a pump rebuild as I dont seem to be leaking air from other parts of the vacuum system....

Try replacing the check valves first.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

I thought of that, but it has the same problem when I take off all external hoses and block off the connecting ports to the main booster line.