Rather than speculate it is probably fuel starvation or very low to no boost. First make sure the line and fittings to the alda are not obstructed.

Too typical of these to ignore. It could also be very late in timing. Smoke out the tailpipe might also indicate that.

Open the return from the injection pump. Fuel flowing out at idle and when you rev it? If there is close that line for a test.

Problem is severe enough cause should be easy to identify. That the car will not go fast is a major clue.

I guess considering glow plugs when having cold starting issues would be no brainer, but this car starts on the first bump at 50 and 60° so it didn't occur to me.

My mechanic buddy thought that was good enough proof of good compression. He didn't have a suggeston about getting more power.

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Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

I haven't yet read about rebuilding injectors. I'll look into it. I have experience with improved injectors (gasser) on my E30. I put in the next-gen injectors, rebuilt professionally, 4 ports instead of one, better atomization - wow, noticeable power increase and it was already fast.

Will have glow plugs in the mail soon. Need to read up on reaming the carbon.

Tonight I looked at the ALDA. I'm embarrassed I didn't notice it sooner. I don't think my mechanic buddy saw it either. The line not clogged but broke:





Don't think I did it while working on the engine. I was never in that vicinity. The banjo bolt is plenty clean. I'll need new line, not going to slide over this fitting.

I have a mighty vac vacuum pump. Is that useful for checking the ALDA? Or is the pressure the wrong way?

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

I think greazzer rebuilds them for reasonable money.

that explains your low power problem.

you need a reamer that goes into the glow plug hole

To me, odds are with the new hose it will run a lot better. The car should run 100 mph if things are all working correctly.

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The ALDA uses the pressure from the turbo to increase the fuel flow from the injection pump, so using a miti-vac to put pressure into the ALDA is correct, but limit the pressure to 15 PSI. If the ALDA leaks down quickly or won't hold pressure at all, you may be able to take it apart and replace the o-rings to fix that.

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Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

So what, just put the mighty vac tube on the banjo bolt lead and apply 15 psi of vacuum? I'm going to need to remove that old bit of plastic tube from the lead anyway.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

Many on here including me have had Greazzer rebuild injectors. Reasonable price, fast turn around and much easier than sourcing parts then going through the learning curve.

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.

Yes, exactly that .

If it won't hold vacuum you'll soon know .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Obviously if the car was sluggish from the first time you drove it. You did not create the problem..

Just before you hook up the new hose to the alda. Blow on the end to make sure there is no obstruction in the over boost valve or the manifold connection. That line when functional does not really have constant air flow as such. It relays the air pressure from the manifold to the alda. By just compressing the air.

With that line open there would have been air flow. This might have included some of the egr garbage fed into the manifold going through that line. That increased the chances of soot buildup in the manifold fitting and the over boost protection valve.

So you just make sure that the system is still open by reducing the air pressure applied. Or just take the car for a short drive to make sure the sluggishness is gone. The engine was just simply fuel starved.

I likes me the sound of this.

Does it have the same thread as the glow plugs, sort of like a tap but not as agressive? I've seen the kits you can buy to extract broken glow plugs, it's not that kind of thing is it?

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

I can't find that hose stock at Pelican. I'll send an email.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K

It just looks like vinyl hose basically. Sold at most hardware stores. Take the barb with you after removing the piece of old hose to check for fit.

link to a om617a reamer (connect mercedes and source together if I try to post it as one word the link gets blocked): https://mercedes source.com/store/heavy-duty-carbon-reamer-pencil-glow-plug-chambers


more on reamers:
https://www.youtube.com/watch?v=bdsojoTJ0p8

Good stuff. I deleted the part about how to get to the site. Who knows, they don't like to be a platform for a competitor, not that I think they'd search every post.

I've heard of the trouble in getting reamers out. I don't have any Kroll, I have some PB Blaster. Probably wouldn't hurt to spray some on now. I'd hate to need to spring for one of the extractor kits now. IIRC I've read of home made reaming tools.

But yes, I think I'll be getting his reamer and the wrench that goes with it.

__________________
Te futueo et caballum tuum

1986 300SDL, 362K
1984 300D, 138K