1982 240 D - Vacuum pump diaphram - leaking - PeachParts Mercedes-Benz Forum

diesel_pinz · #1 10-09-2003, 03:45 PM

Hello everyone I want to thank everyone for all of the information that is shared in this forum - its great. I have decided that I have a leak in my diaphram - looks of white/blue/grey smoke at idle - running rough - etc.... I bought the vacuum pump diaphram repair kit - and I got 5 of the 8(I think) screws off but the other 3 stripped and bad. Any ideas? I have read through looks of the post on this issue and I came across a quick fix of by-passing the vacuum pump with a 3 foot 7/16 foot hose going from the brake booster to the intake manifold. All of the post that I read said there should be a clear hose going from the vacuum pump to the intake manifold - but after looking at my vacuum pump at least 50 times looking for another clear hose going to the intake manifold -I found out the the later model 240d do not have this hose and - it "vents the air from vac system into the crankcase" - can I do something else or connect the hose somewhere else?? I don't like the smoke and will not be able to deal with the stripped screws until next week.

Thanks Everyone in Advance

Brian

leathermang · #2 10-09-2003, 08:00 PM

Ok,, hopefully those screws are not all in a line next to each other....
There are ' self tapping ' screws which can be bought...take one of the good ones to a speciality bolt shop and explain what happened... look in Yellow pages under ' bolts'.... color code them and paint the pump where you can tell where to reinstall them the next time it has to come off....

kerry · #3 10-09-2003, 09:50 PM

I think there may be a more fundamental question here. If you don't have the clear hose to the air cleaner, do you have a pump with a diaphragm? I am under the impression that the pumps without the clear hose were not diaphragm pumps but piston pumps. Also, if you don't have the hose to the air cleaner, I don't see how a bad pump can be causing the engine to smoke since I think the bad diaphragm put oil into the combustion chambers via that clear hose to the air cleaner. So, the source of your smoke must be elsewhere (I think) unless someone can explain how oil would get into the combustion chambers some other way as a result of a bad piston pump.

Kyle Blackmore · #4 10-09-2003, 10:25 PM

When my diaphragm went in my 300D,the oil into the air filter went from a light mist to a large puddle dripping out of the water drain in the air filter housing in a matter of days.Re: the stripped screws- try some valve grinding compound on the screwdriver tip or a pair of needle-nose vise grips on the screw head . A phillips head that's stripped can also be persuaded off with a square drive (Robertson head) screwdriver. Good luck.

leathermang · #5 10-09-2003, 10:41 PM

Guess I was reading that wrong.. thinking the threads were stripped....
You might have to take out the radiator to do it...
But the very best way to deal with bad phillips head screws is a hand held impact ... hit it with a hammer... this is what saves motorcycle mechanics.... LOL
But it takes some room to have it in place and get a little swing at it...
Ps, be sure you have it adjusted so it goes the correct direction.. or it will surely take the screw head clean off or take out all the threads from the inside of the hole....

diesel_pinz · #6 10-19-2003, 02:16 AM

Hello and thanks for everyones imput on the vacuum pump problems. Well I finally got the screws out but I busted off two of the heads - and after all of that I found out the I had the wrong repair kit because I have the piston type. Put it back together and the pump did not have a good seal so it would not shift out of first and it would not turn off. I figure hell I want to save myself from buying a new pump so I tried the kit - did not work - so - I call a couple places and found one for 65.00 - good idea? Anyway had to remove the radiator and outher things but finally got the pump off and now I am trying to put the new one on it does not seem to want to go. My question is - it seems like the bolt that is underneath it on the engine it blocking it from goin on - not sure what that bolt is but it has a 1/4 inch washer ( maybe less than a 1/4) steel -almost looks like a bearings but it is not. And the bolt is not screwed all the way in I loosen it and it seem to be only in a turn or two - so the washer could move back and forth. The bolt is threaded all the way - should this be flush tight anginst the washer?? I am going to try to take a picture tomorrow - o ya - when I remove that bolt oil seems to come out?? this might help.

Thanks in advance for your help

wgreen · #7 10-19-2003, 01:31 PM

a picture or two of that area would really help.......

diesel_pinz · #8 10-20-2003, 01:30 PM

the bolt inside the circle is the one that I question - anybody know what part that is? and should it be flush tight?

Stevo · #9 10-20-2003, 04:15 PM

OH GEEEZ

You say this bolt was lose,

Yikes, Thats the timing device and I would put blue lock tight on it and torque that puppy down. The injector pump is on the other side. I am hopping someone else can explain a little more about this timing device.

When you put the pump back on have the valleys vertical on the little "roller coster" track (turn the engine )

diesel_pinz · #10 10-20-2003, 04:40 PM

Stevo -

Thanks for your reply - I think the threads on the bolt are messed up because I can not torque it down any further - I might be able to, but I don't want to strip something on the inside? or should I try to torque it down hard? do you have any idea the name of that bolt? - I would like to buy a new/used one -

Why and how do I get the valleys vertical?

Brian

Stevo · #11 10-20-2003, 05:29 PM

Brian

If it looks like you are having trouble with the threads you better stop right there and wait for someone that knows more than I do. I do know that getting that T/D out with the timing chain wrapped around it, is a bugger so you dont want to have to take it out. That shaft that the bolt is screwed into goes all the way through and you must remove the sprocket first to get it out. Lets stand by, Is lucky you caught it. I would call that bolt
"the BIG ONE" They would know if you described where it came from, maybe someone has the part#
To get the valleys vertical, turn the engine (clockwise) as you would when adjusting valves

Steve

Stevo · #12 10-20-2003, 05:53 PM

Brian

OK I just happen to have a 616 up on end with the vac pump off and the T/D bolt (The BIG ONE) lose. I was wondering if someone could have used a bolt that was too long or a washer that was not fat enough.... so the bolt measures 45mm long (1.76") and the washer is 8 mm thick (.3") So this will be something to check out and make sure you have the proper bolt and washer.

Steve

diesel_pinz · #13 10-30-2003, 04:59 PM

I found a new bolt and put it in and then I was able to put the new vacuum pump on. To get this bolt in I had to do use a good amount of elbow greasy. After I got the car back together - I had a real hard time getting it started. It really took me alot of effort - cranky for 5 minutes starting for a second and then stall. This went on and on and finally after giving up and trying it the next day it's back to a normal start and runs. The only problem is it runs different than before. There is almost NO LOW END power - once I get going (15 or 20) it seems to be fine except for the smoke (at low end and at running - varying on the amount I am stepping on the pedal ( Different smoke than before with the bad vacuum pump - this seems to be a good amount of regular diesel smoke - grey / black / heavy.) ) It also seems to be running louder than before - pretty loud nailing. And it also seems like it is studdering when cruising. I also notice that the back of the car is dirtier (very dieselish - from the smoke). And it seems like it might be running a bit higher in temp. Any ideas where to go? I would be glad to provide more information.

Stevo · #14 10-30-2003, 06:23 PM

Brian

Sounds like a timing issue. Youl get more opinions on this but I think you need to check timing and I would go so far as to say if your chain has jumped a tooth it could be out, what, 18 degrees, I think, so that could cause damage. Don't want to cause a panic attack but better to be safe. There is lots in the archives about timing. I use the bubble method (don't want to get into a pi**ing contest here.

) Was the old bolt the right length (washer the right thickness too) and the threads gone, or what. The bolt should have threaded in EASY then come up hard & tighten down then.

Steve

diesel_pinz · #15 10-30-2003, 06:44 PM

the bolt was the right one - the threads were pretty damaged on the old one so I think there might have been some damage to the threads on the inside. I was thinking it was the timing chain too - on a scale of 1 to 10 - how hard is it to do compared to the vacuum pump?