I need some help. I have an 85 300SD and I recently broke my ALDA by over-adjusting the screew CCW. I can now turn unscrew the top screw all the way out. This results in unsafe drivability as I can not even get power enough to climb my driveway without a good running start. I have almost no power off the line now, which is what I was originally trying to increase.

I read about removing the innards of the ALDA, but the screws holding it together are locked in good. I did remove it from the IP in order to try this and now I'm wondering what my options are from here.

I haven't found any available on ebay, and I haven't found a local junk yard with any old mercedes diesels. So, I'm wondering:

* Anyone know where to get an ALDA without an entire IP?
* Can I temporarily or permantly drive the car without causing damage with the ALDA removed?
* If so, what do I do with the two hoses that were connected to the ALDA banjo bolt? What about the large nut on the IP that the ALDA screws into? Should I cover it?
* Is running with the ALDA removed the same as running with it on and the capsules removed? (Not that I can get the thing apart.)
* Are there any other options that I might not be aware of?

This is my daily driver and I really need to get it back on the road. Thanks in advance for the help. I'm trying to take a more cautious approach to things from now on.

Brian

Screw nut where you thought it was before.Take a zip tie,or larger hose clamp to hold screw in while driving. It works.

* Can I temporarily or permanently drive the car without causing damage with the ALDA removed?
ONLY if you install a boost gauge and actually watch it.

* If so, what do I do with the two hoses that were connected to the ALDA banjo bolt? What about the large nut on the IP that the ALDA screws into? Should I cover it?
Plug the hoses. The IP is fine, it has a seal on the shaft. You can also remove the guts of the ALDA and reinstall it to work as a dust cover.

* Is running with the ALDA removed the same as running with it on and the capsules removed? (Not that I can get the thing apart.)
Yes.

* Anyone know where to get an ALDA without an entire IP?
You can always offer somebody here a few bucks to go to a junkyard and pull one for you.

No, it doesn't. Once that screw breaks out the alda has been destroyed.

There are guys here that run with out the ALDA with no problem. If you have that much loss of power I would look at other things first like the line on the back of the intake manafold to the ALDA being broken so the turbo is not building pressure. The only big worry with the ALDA removed, to me, would be stuff getting into the IP.

__________________
1983 300SD
200000miles

Forced been driving 2 months same good mileage and no smoke.I sealed screw with rubber washer.
Machinist 40 years.

You are driving around with a 1/2 dead ALDA and only getting 1/2 your possible boost-enrichment, of course you are going to get good mileage and no smoke. What is your 0-60 time? 18 seconds?

I don't care how many years you've been a machinist, how many years have you been a diesel technician?

Once that screw has broken out the capsule inside has lost its seal, no longer functions and cannot be repaired. At that point the only repair option is to replace the entire ALDA.

Whilte we're on the topic of ALDA removal(I'll be doing it to my car tomorrow)
Who says you couldn't take the entire square IP cover off and duplicate it; minus the ALDA hookup?

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

On the left is how an intact ALDA looks inside. Notice the screw, its soldered onto the top capsule.

On the right was my ALDA after I broke the screw doing the exact same thing BrianC did. Notice the hole? The capsule has a precisely calibrated pressure inside and the screw is a plug that seals it. Once that screw breaks the seal is broken the calibrated pressure is vented and there is no way to fix it.

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There would be no place for the linkage inside. The said linkage is riveted to the lever deep inside the governor and the only way to remove it is to cut it off. I wouldn't do it on the car, metal filings in the governor and injection pump are not something I want to think about!

Just take it off and forget about it. I did on the 300SDL and there was a big difference. Now the SDL actually gets off the line nicely. As Forced said, you should watch the boost as you could possibly run into t situation where the wastegate does not work and boost pressure goes into dangerous levels. Make sure the wastegate hose is intact.

__________________
"I have no convictions ... I blow with the wind, and the prevailing wind happens to be from Vichy"

Current
Monika '74 450 SL
BrownHilda '79 280SL
FoxyCleopatra '99 Chevy Suburban
Scarlett 2014 Jeep Cherokee
Krystal 2004 Volvo S60
Gone
'74 Jeep CJ5
'97 Jeep ZJ Laredo
Rudolf ‘86 300SDL
Bruno '81 300SD
Fritzi '84 BMW
'92 Subaru
'96 Impala SS
'71 Buick GS conv
'67 GTO conv
'63 Corvair conv
'57 Nomad

Ah, so that will be a modification that gets lumped in with the rack limiter removal this winter

__________________
$60 OM617 Blank Exhaust Flanges
$110 OM606 Blank Exhaust Flanges
No merc at the moment

Thanks everyone for the extremely helpful information. I think I'll try it out without the ALDA.

I picked up a boost guage per ForcedInduction's recommendation and am going to hook it into the port on the intake. One thing I'm not experienced with is wiring up accessories like this. For this guage, I believe I've got a ground wire, one for the +12V, and one for the dashboard lights.

Do I just hook these wires into the fuse box somewhere?

Brian

The boost gauge should have two electrical connections and a port fot eh pressure tube. WHat you can do is splice the electrical connections into the dashboard lights. I tapped the wire lighting the ashtray. I installed my gauges in the sunglass tray under the ashtray in the 300SD. I ran the tube from the intake manifold through the hole in the firewall where the electrical wires go to the fusebox, over the steering column and down the inside of the center console. I had to take the panel under the instrument cluster out and the wood panel under the shifter. I also removed the ashtray to get the the wiring.

I then ran the wire from the exhaust temp gauge (pryometer) using the same path. I bought matching VDO gauges.

__________________
"I have no convictions ... I blow with the wind, and the prevailing wind happens to be from Vichy"

Current
Monika '74 450 SL
BrownHilda '79 280SL
FoxyCleopatra '99 Chevy Suburban
Scarlett 2014 Jeep Cherokee
Krystal 2004 Volvo S60
Gone
'74 Jeep CJ5
'97 Jeep ZJ Laredo
Rudolf ‘86 300SDL
Bruno '81 300SD
Fritzi '84 BMW
'92 Subaru
'96 Impala SS
'71 Buick GS conv
'67 GTO conv
'63 Corvair conv
'57 Nomad

Remember that the port on the intake is metric, M10x1.0, not NPT (pipe thread). They are close but not close enough.

Ah Thanks for the info. Mine came with the NPT fitting. I went to the local autozone, which didn't have an adaptor.

It looks like some people have T'd into a hose going to the ALDA.

*Since I removed mine, can I just use one of the lines that I plugged?
*Should it be the clearish one which was connected to the banjo fitting (not the one connected to the bolt itself)?