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  #1  
Old 04-22-2004, 08:24 PM
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Unhappy w123 strange vacuum system

my 83 300D did something funny today.

when i was driving home, the power brakes went out.

then, the tranny started shifting harder (but not as bad as a vacuum line completely disconnected - i've experienced this too).

when i tried to shut the car off i had to open up the hood and do it manually.

the funny thing is, i think the power door locks still get vacuum.

i've searched the forum and got some valuable information, but i was wondering if anyone had any ideas about my specific situation.

also, i checked the vac. valve on the injector pump. i don't know it's name but it's the one bolted on to the ip and i can't tell if it has oil on it or not. there is some black stuff that looks more like rubbing from the hose, but it could be oil (?).

any help is appreciated.

thank you

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  #2  
Old 04-22-2004, 08:37 PM
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i just checked the doorlocks again and they didn't work.

i guess there was just left over vacuum in the lines.
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  #3  
Old 04-22-2004, 08:56 PM
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Sounds like a massive leak...

I hate to say it but you will just have to start at the vacuum pump and go from there with your testing. Start at the first connection and then work your way out isolating as you go.
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  #4  
Old 04-23-2004, 09:22 AM
LarryBible
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Fisherman offers the correct approach. The only thing I would add is that if the vac pump is your culprit, when rebuilding make SURE that the roller rolls smooth and everything around it is solid. If that roller breaks it can fall into the engine and hand grenade it.

Good luck,
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  #5  
Old 04-23-2004, 11:57 AM
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thanks guys

what is the roller?

is the power breaking mechanism controlled by vacuum?
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  #6  
Old 04-23-2004, 12:34 PM
LarryBible
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Yes the power brake booster is controlled by vacuum as are 95% of them on light vehicles.

The vacuum pump is mounted at the front upper, drivers side of engine. A large line connects to it that goes to the brake booster with several nipples that provide vacuum to accessories such as shut off and vac locks and modulator if an automatic transmission.

Put a vacuum gauge on one of the nipples and see if you have vac with engine running. If not, break loose line at vac pump and see if you have vacuum from pump. Be careful, the fan is spinning very close to the pump.

If no vac from pump remove it. When you do, you will see a roller on the engine side of the pump that rides on an eccentric that is on the Injection Pump sprocket mechanism. That roller should be in good shape, smooth and solid. If not replace the entire pump, if the roller is okay, simply get a diaphragm kit and rebuild the pump.

If there IS vac at the pump then you need to start applying vacuum everywhere until you see where it does not hold vacuum and that is your leak.

Good luck,
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  #7  
Old 04-23-2004, 04:26 PM
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Man, Larry, YOU ROCK! Problem...answer...next!...1,2,3 (pun intended)...
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  #8  
Old 04-26-2004, 12:26 AM
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is it possible this is my problem.

Today my new (to me naturally) 79 300d w123 (if someone would tell me if i am just supose to say W123 or just 300d you could really assist me socially) was also doing some funky things. The truth is it has since I have wowned it (one week)and it was cheap so it is expected. However today was the worst of em all. Not only did my car not want to shut off despite that my keys were coming out of the ignition after it was turned to the off position, but all of my AC things now magically stopped working in the past 24 hours or so.

I did change my oil yesterday. . .and there was a lil black hose in the way that got bumped off a bunch. . .and it certinaly had either compressed air or a vacume noise coming from it even when the vehicle was off. . . but I preyed we didnt hoze anyting and I didnt appear to.

This is just sounding as I ma into this post like it could be down the ally of my issues.

Djinn
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  #9  
Old 04-26-2004, 08:30 AM
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djinn:
Welcome aboard! As far as 300D or 123 goes, the easiest thing to do is just put the year and model of your car in your signature (click on the "user cp" button on the top right of this frame). Then you can say 300D in your posts and anyone who would be able to help you would already know it was a 123.

As far as your post goes, you answered it yourself. The vacuum hoses are the hoses right above the oil filter housing and if you knocked any of them loose (which is common during oil filter changes), the resulting loss of vacuum will cause your problem. Find which one is leaking and your problem will be solved.

The ignition switch cuts the fuel to the IP via a vacuum "switch". No vacuum = no shut down. Additionally, cars with leaky vacuum systems will sometimes need to run for a few minutes before they have stored enough vacuum to shut down via the key switch. The vehicle stores vacuum in a few locations which is why you kept hearing it when the car was off.
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  #10  
Old 05-10-2004, 08:04 PM
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Fixed it

Thank you all for your help.

I got your advice and looked a whole slew of stuff on the issue from this site and others, while awaiting the arrival of my MityVac!!

Given the condition of my vac system the documentation primarily confused me, but I read the hell out of it all the same!! To give you an Idea I am confidant that hte locking system has been completely taken out of the loop and the component that would appear to have the lines that go to those locks is not even mounted nor does it have any of the big black hoses attached to it, although i think i located black hose # 2 last night. . .thats correct just free floating in my car!!

After spending hours looking at stuff I decided to just go at it!. I started where I knew we knocked off the line and got no pressure from the side the sucking was coming from previously. . .nothing! Then i moved to the other side and wham!! needle jumped. I worked my way to the four way and found that no device beyond the four way was getting pressure. The little yellow thingy withthe two hose nipples only had one attached hose and upon attaching the mity vac to the exposed hose I saw the needle jump.I noticed two lines that were not occupied coming from the firewall to that general region (however no coupler??) so i attached it to the first yellow one using ahose that came with my new beloved tool (that's correct the MityVac to the rescue once again), and killed the key and bam it died. . .I then danced a lil jig and proceeded to try the same procedure withthe other mysterious yellow vacline coming out of the dash. . .I did not have the same results!!. . .so I returned it to my origional coupling and tried the AC. . .it all is better now.

Believe it or not that was the condensed version of the procedure. . .and I suppose what I am getting at is I still dont know what an IP is or what I even did for that matter. . .but it works and the Jig flows on!!!!!

This car needs a lotta luvin and I now dont knwo where to begin. . oil leaks and slow preformance, electric window oddities, Door vac systems. . .Identifying the misc. piece of floating unmounted hardware under my hood. . .the options are seriously limitless. . .I am currently happy with my success and if you all knew how little I know of mechanics you would never get in my car after I knowing I worked on it. Everyone has their skeletons in their closets!!

Thanks again

J
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  #11  
Old 05-11-2004, 09:26 AM
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Exclamation

Welcome to the forum.
Please do not expect neck snapping acceleration from your 300D. Please do not expect to feel the back of the seat as you press into it under the power of the MB 5 cyl, Just be happy that it gets you from 0-60 in 20 seconds (or thereabouts).

Your education has begun. You have a steep learning curve ahead, make use of this forum to Search for the answers to your porblems, then ask an informed question of the members.
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Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.
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  #12  
Old 05-11-2004, 07:55 PM
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Quote:
Originally posted by TonyFromWestOz
Please do not expect neck snapping acceleration from your 300D. Please do not expect to feel the back of the seat as you press into it under the power of the MB 5 cyl, Just be happy that it gets you from 0-60 in 20 seconds (or thereabouts).
Tony you are correct, it is a stepe curve. I have a few things going for me. First is this forum and the info and people contained therein. Secondly, I bought a cheap car that I am only a little afraid to screw up. Number three (and perhaps the most important), I am on a personal rennisance of sorts and have a burning desire for knowledge. . .right now. And lastly. . I am now reemployed (Starting the monday after my purchase) and although this will take some time away from my hobbies. . .it does wonders on the spirits which goes quite a long way!!

As for your quoted posting . . I am aware of what it should do and kinda have an idea of what may be wrong. I counted 30 seconds to 50. . .which by everyones estimations is pretty slow for this car. I never expected to break the sound barrier. . .but I do live in the sount and many yahoo's like to ride up on me and have a lil road rage fit. . .so out of courtisy I am trying to do all I can!! I plan on running WVO or B100 in the long run (probably WVO first, for obvious reasons), which although shouldnt affect this . . .it wont help it either. I have a ton of blowby and suspect that my engine is worn. Should a worn engine produce a slower acceleration. That may seem to be a stupid question. . .but I know there are no stupid questipons. My logic just tells me "Naturally it will you jack@ss"!!

Any how you can feel free to answer the question or not as I will find on my own anyway!!

Thank you all again. . . at the very least it is nice to have a supportive group that doesnt think you are nuts when you tell them what you are going to be doing!


J
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  #13  
Old 05-11-2004, 10:58 PM
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OUR MB's SUCK
When our cars DONT suck they run like shiat ROFL
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  #14  
Old 05-13-2004, 01:32 AM
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is your 300 still soon to b a daily driver?
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  #15  
Old 05-13-2004, 08:12 AM
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Djinn,
You will see from my signature lines that I recently did a heart transplant from Fatmobile 2 to My wife's Josephine and Vice versa.
The Fatmobile 2 had a motor with ~220 000km on the clock. Josephine had ~380 000 km on hers.
There was a very noticable difference in acceleration (which is why my wife wanted the swap).
This difference is MUCH more than the difference in mileage should cause, given similar treatment over the years.
As I do not know Josephine's history, I cannot comment. Fatmobile 2 however was owned (2nd owner of the car) by a MB mechanic, who serviced it for the first 23 years. His comment was that "That motor is a one in a million. Everything came together perfectly at the factory and it just spins out better than any other OM617 I've ever seen."

So there are motors which were good when new, there are motors which were GREAT when new. The treatment they recieve over their lifetime is a greater influence on their performance after 20+ years on the road.

I am now used to the (lack of) power of my car (Fatmobile 3), my wife is happy, LIFE is GOOD.

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Fatmobile 3 84 300D 295kkm Silver grey/Blue int. 2 tank WVO - Recipient of TurboDesel engine.
Josephine '82 300D 390kkm White/Palamino int.
Elizabeth '81 280E, sporting a '79 300D engine.
Lucille '87 W124 300D non-turbo 6 cylinder OM603, Pearl Grey with light grey interior


Various parts cars including 280E, 230C & 300D in various states of disassembly.
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