85' 126 project car !!!Help!!! :) - PeachParts Mercedes-Benz Forum

polarisrmk · #1 05-07-2009, 12:26 PM

Ok so i have been on this forum reading for about the past month the do's and don't's of the mercedes diesels. I am a certified marine technician, audi/vw technician, and BMW freak. This is really my first shot at the mercedes diesel but they have always intrigued me. For starters bought the car (1985 300SD) for $950. Car has 291K on it engine only has 91K on it. Previous owner spent over $8000 in the last two years on various vacuum issues, new engine (not rebuild), ect (have reciepts for all). Heater core went kaput a year ago and the thing has been sitting ever since. I bought the car for a steal, as he didn't want to put any more money into the thing. Long story short Dash and HVAC is now out of car after much bad language and many referances to this forum. I am replacing both the heater core, moldy A/C evap, and one faulty vacuum element. Is there anything else that i should be replacing while i am in here. All vacuum hoses seem to be good and i have treated everything with Wurth "Rubber Care". A must for german car owners, and I can't beleive noone on the forums has mentioned it! It saves all your rubber parts and brings old ones back to life

.

On to the under hood goodies. I have decided to get rid of the EGR and block it off (seems to be a no brainer

) . ARV valve confuses me i haven't quite decided what to do there seemst to be mixed feelings about this little thing (any help would be great!). I want to turn the boost up to 12 PSI and i work for a company that produces superchargers and boost controllers and the like, so i will be putting electronic boost controll on the thing and various other gauges

. Ok What to do with the ALDA???? Some people say remove it, other say leave it alone, others say shim it. WTF do i do

! I want to make this thing run like a raped ape but keep decent reliability and longevity. I am thinking Intercooler or possibly supercharger fed turbo (gotta love connections).

I am sure i will think of more things to ask.

TX76513 · #2 05-07-2009, 01:18 PM

Welcome to the Forum!

No sense replacing anything that's not broken. With that said as soon as you get the dash back together you will probably have a vacuum pod go bad. They are a little pricey to just replace them since you got her opened up. With time you will be a Pro and entering the dash area through different locations - trust me.

If you read enough if the threads on the Alda - there are as many good experiences as bad. For the time being I would leave it alone. My thoughs are that MB did a pretty good job engineering a good balance between economy and performance.

$950 is a great price, congratulations these are wonderful cars. Something else you will probably read here also. There is nothing more expensive than a cheap Mercedes.

Skid Row Joe · #3 05-07-2009, 01:44 PM

If you are versed with VWs and BMWs......I don't see anything you won't be able to handle on these MB diesels. You're in the right place.

polarisrmk · #4 05-07-2009, 03:06 PM

[QUOTE=TX76513;2194632]Welcome to the Forum!

No sense replacing anything that's not broken. With that said as soon as you get the dash back together you will probably have a vacuum pod go bad.[QUOTE]

Thats what happend on my 124 in florida. A/c always blew out the defrost and fogged the windshield up argh!!! but they are about $80 a piece so i am going to just replace the one.

TX76513 · #5 05-07-2009, 03:10 PM

Fair enough sounds like you know how Murphys law works with MB's!

LUVMBDiesels · #6 05-07-2009, 03:14 PM

Welcome to the club!

One other thing, I would suggest is to join the MB Club of America at mbca.org and go to your local chapter meetings. You will meet lots of people who know and love these cars and can you can learn many tricks from them...

Good Luck.

BTW, on my 300 SD I just backed the ALDA screw out 1/2 turn and it made a world of difference in off the line power. I also had a mechanical boost controller set at 14psi (to go any higher without more fuel is a waste)

On the OM603 I have now in the SDL I just removed the ALDA.

I also blocked off the EGR and ARV valves. If you take the EGR valve off the intake, the hole is the perfect size to be blocked by a quarter. I went all 'authentic' and stuck a 1981 quarter in my 1981 300SD

WDBCB20 · #7 05-07-2009, 03:21 PM

The rubber diaphragm insert can be replaced for the 3 single chamber pods 104, 107 and 110 but not the 3 dual chambered ones 95, 98, 101. The picture shows the innards of a dual chamber pod. The rubber diaphragm number 1 is similar in design to those found in the single chamber pods. This can be replaced. Number 2 can not be replaced because the rubber is compressed between the outer and inner wall of the cup which holds the rubber in place as indicated by the red arrows.

The 3 single chamber pods 104, 107 and 110 are less likely to fail, require much more disassembly to reach and remove, but are cheapest to replace by just changing out the rubber insert.

95, 98, and 101 are doomed to fail sooner rather than later if they are as old as the car. But they can easily be accessed by removing the glove box. 95 and 98 -the two mounted together directly behind the glove box, close the outside air (recirc) flap entirely (when the "O" extreme right button is pushed on the CCU button panel) or most of the way (when AC is on and max. cool is dialed in on the temp wheel). if they're not working your AC will never cool properly because the flap stays open allowing warm outside air in to blend with the cooled air. When 101 fails the system defaults to defrost directing all airflow to the windshield.

Conclusion: replace rubber insides of 104, 107 and 110 "while you're in there" and replace entire pod when 95, 98, or 101 fail.

polarisrmk · #8 05-07-2009, 03:33 PM

107 has failed on mine and the system defaulted to defrost. whats up with that? The climate control unit has been resoldered recently but it seems as though the wrong buttons activate the wrong vacuum elements when i had my guages and testers hooked to it. is it possible to hook something up wrong inside that control unit? I have not opened it up yet as my main goal was to get the damn heater core out so it would stop ruining the carpet. Had to bypass the heater core to get the car home when i bought it and up here in the mountains it is still pretty cold in the middle of april at night. Was a cold ride.

polarisrmk · #9 05-07-2009, 03:35 PM

Quote:

Originally Posted by LUVMBDiesels

Welcome to the club!

One other thing, I would suggest is to join the MB Club of America at mbca.org and go to your local chapter meetings. You will meet lots of people who know and love these cars and can you can learn many tricks from them...

Good Luck.

BTW, on my 300 SD I just backed the ALDA screw out 1/2 turn and it made a world of difference in off the line power. I also had a mechanical boost controller set at 14psi (to go any higher without more fuel is a waste)

On the OM603 I have now in the SDL I just removed the ALDA.

I also blocked off the EGR and ARV valves. If you take the EGR valve off the intake, the hole is the perfect size to be blocked by a quarter. I went all 'authentic' and stuck a 1981 quarter in my 1981 300SD

I will try your advice on the ALDA .... do you know what the base setting is? It may not be right from the get go but the car does run well and seem pretty quick compared to most i have driven.

toomany MBZ · #10 05-07-2009, 04:34 PM

If your ALDA is sealed, it's at the factory setting.

polarisrmk · #11 05-07-2009, 05:47 PM

ALDA is not sealed.... Motor was changed 91k ago and pump has been rebuilt so who knows what whoever has done to the setting on the ALDA

ARINUTS · #12 05-07-2009, 09:50 PM

when you floor it, is there black smoke? that means there is (more than) enough Fuel.

I turned the ALDA screw counter clockwise all the way out. (Just make a note to remember the original setting.) then I went for a spirited ride. the black smoke was very obvious. then I screwed the ALDA back in until I felt that the power was the same as full blast, but less smoke.

Blake smoke = unburned fuel , so why waste it

I'm also a Bimmerphile where are you located?
01 740iL sport
97 328is
93 740iL
89 325i
87 L6 ( soon to be boosted )
87 325i Turbocharged
85 745i ( euro / factory Turbocharged)
84 745i "
83 300SD

polarisrmk · #13 05-08-2009, 11:21 AM

Have not driven it since i bought it i will have to check on that... As i recall it was no more than usual... I like your method better than anyone else... BMW people typically have great insight

I am in utah .... land o Xi's and ix's
Drove the new 335D I think i am in love

polarisrmk · #14 11-04-2009, 08:17 PM

UPDATE!!

Have been driving the car now as a daily driver 50 miles each way up a steep canyon. I absolutely love the power and smooth ride of this car.

My latest issue though is I want to put nicer wheels on it. So i went out and bought some 2001 E class wheels with tires here locally. I had to use spacers to get them on the car. They look beautiful!!

Took the car over to have them balance the tires today and the tire shop said all the tires were perfectly balanced and that the wheel spacers were causing the vibration

Now i am thinking that i am going to have to sell this set of wheels to get ones that dont need spacers. My question is what should i be looking for? It took me forever to find these ones and I really don't want to get rid of them but i cant have a wheel falling off or the massive vibration above 55mph. I keep trying to get help but they keep moving my posts to the wheel and tire section which noone reads so i am hijacking my own thread to get an answer from you diesel guys. Please help with any insight.

PS i have a nice set of E class 16" wheels with brand new snow tires on them for sale!

bsmuwk · #15 11-04-2009, 09:04 PM

Vibrations will go away with a good quality set of hubcentric 5x112 spacers.