My engine needs more than the 25 psi I make at full throttle going 80 mph or the 22 I make at 70 mph. That or I need a much much better IC and many other "tricks" to burn all the fuel I put in. But then I'm one of a very few with a pump that can put out way more fuel than stock. If you are blowing black or dark smoke you need more boost until the egt readings tell you to back it off.

Im still smoking pretty bad at 20 lbs... maybe a intercooler would be a good addition

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1996 s10 zr2 with a 6.5 turbo diesel
1996 c2500 suburban with a 6.5 turbo diesel
1981 300sd with a turbo 617
Monte carlo figure 8 car

I'd like to have the fuel to smoke, ...

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Gone to the dark side

- Jeff

id rather have the power without the smoke, but if i have to deal with smoke to make power then i shall.

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1996 s10 zr2 with a 6.5 turbo diesel
1996 c2500 suburban with a 6.5 turbo diesel
1981 300sd with a turbo 617
Monte carlo figure 8 car

Agreed, sort of. I'm building a 603 rignt now, trying to SWAG the fuel increase, boost increase, timing, and turbo size so that I will hopefully get good power with reasonable smoke and EGTs at full-throttle. I wouldn't be betting on me getting it right the first time, wish I could afford 7mm elements.

__________________

Gone to the dark side

- Jeff

getting close or not getting close the first time is better than never trying at all.

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1996 s10 zr2 with a 6.5 turbo diesel
1996 c2500 suburban with a 6.5 turbo diesel
1981 300sd with a turbo 617
Monte carlo figure 8 car

I went through the winter with a weak starter and replaced it a month ago with one I rebuilt and no more starting problems so I have time to deal with other issues such as boost.

I tried adjusting the Alda, had it fully C.C.W. and still getting max 9 psi. I then pressure tested the Alda aneroid and it would not hold pressure for very long. I pumped it up with a mini bicycle pump to 15 psi and it would leak down to 0 within 5 seconds or so. Should it hold pressure longer than that and how much longer?
I had shaving cream around the connections including the banjo fitting at the aneroid and saw no bubbles so I am pretty sure the aneroid is the part that is leaking.

What should I be doing next?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

your ALDA is leaking at the seal where the pin goes down to the pump pin.
As the boost pressure source is huge it should not influence much the ALDA work. If you adjust the ALDA all out it does not matter if it leaks.
Or you take it off completely to test boost pressure.

Tom

Thanks Tom,

Anything I have to be careful with so I don't break it? There's no fasteners on the cover other than the slotted screw and 10 mm locknut. There's a big hex nut underneath the cover - looks to be around 27 mm. Is that the nut to remove the ALDA? A link to a good DIY would be appreciated.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I don't have the link right now but yes the hex 27 underneath and a hex ?24? just above the 27 hex to hold the ALDA.
There might be a spacer between ALDA and pump that fall out or stays in.
This spacer is a basic adjustment when the ALDA was put on the pump in the last diesel shop (or by factory). Use this spacer again with the same ALDA on the same pump.
Once removed you can use the shaving foam to see the leaking seal.

Your boost line goes directly from the manifold to the gauge?

Tom

The hard vacuum line from the ALDA banjo was kinked with a pinhole about 6" from the banjo. I fixed it by cutting off the damaged section and splicing a T in with rubber hoses. That T is where the boost gauge is connected.

Could the leaking seal explain the 9 psi max boost? I guess it can ha? With the ALDA off, if I see the leak at the seal with the shaving cream, I'll plug the line to the banjo and my boost should go up along with more power?

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Your 9 psi boost is likely a weak spring in the waste gate. If you have a KKK turbo it is easy to adjust, the garret is a little harder. Look up waste gate adjustment on this site and you should be able to find it. On my 300d it was at 9 psi also, and I put it to 12psi. Stock pump settings on this one. Alda is removed, and egr blocked.

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1977 240D turbo

oh the leaking seal, it is very unlikely to cause any real lose of boost, the volume is just to small, even having the line to the alda off and venting to the air would not cause a lose of boost. Think large volumes of air.

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1977 240D turbo

After getting all the lines cleaned and the boost gauge installed in my 85 300CD I'm seeing a max boost of 8 psi, with a regular boost of only 7. No smoke.

from reading here, It's my understanding that I too suffer from a weak waste gate spring. My boost gauge is tied into the hard line from the banjo bolt also using a Tee.

I have not checked the ALDA yet or done any adjustment to it.

I'm planning on getting out there today and playing with it some more and doing the spring adjustment.

turns out I have the KKK turbo... So I just finished increasing the boost and doing some testing.

Now the boost is around 17 but I saw it hit 19 for a second. I held it at full boost and the over boost protection kicked in at 16 and dumped the pressure... Like it should... So good there.

Now, I need to work on that Alda.. I'm still debating if I should remove it or just adjust it.