I am getting ready to commision my 82 300D for daily driving, and I need to inspect my turbo boost system for proper operation.

My ALDA and the switchover valve look like they have been monkeyed with, so I am working under the assumption that it has all been messed with and needs a total check. Car accelerates great of the line, but top end on the highway seems like it is lacking a bit.

What do I need to do to adjust my system to stock optimal and healthy? I am not interested in boosting performance - just setting to a modest 10psi of boost or so.

I have gleaned from reading the massive amounts of scattered info that I:
-need to check boost at test port on Turbo (I have a AR)
-need to check overboost solenoid shuts down boost when it should
-need to adjust wastegate OR put in boost controller
-adjust ALDA (how do I tell where to put it?)

What's the best order to do this? Tips, good threads?

Thanks so much in advance,
dd

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'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

On my old 83, I got one of the boost controllers that you splice into the wastegate line... It was from Dawes performance or some such place - a very popular item on this board 3-4 years ago.

Get a cheap 0-15 psi boost gauge from AZ. Clean your banjo bolt, then follow the line from it to where it goes to the prssure controller thing that then leads to the ALDA. On the inlet side, use a 3-way vacuum hose, and get the pressure gauge in there.

Turn the boost controller up so that it lets a lot of pressure build up. After fully warming your engine/oil, get on it hard, and see that you easily get over 15psi. Good to go.

Adjust your boost controller to give the 11.1 or 12.1 or whatever the correct pressure is per the spec, I forget.

You should be able to test the pressure on the other side of the solenoid the same way.

As for ALDA correction, can't help you there. I dont recall enough from the old days. Might get back into it now though.

JMH

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Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)

http://www.serenitysys.com/MB/Service_Info/Turbo_Tweak/tweaking_the_mercedes_617_turbo_.htm

JHZR2 - thank you for the info on the controller
Lance - thanks for the link, that very helpful for the wastegate adjustment

Do they have good enough handheld (not to install) boost gauges at AZ or NAPA?

So how does the ALDA adjustment play into all of this?

Thanks,
dd

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-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

IMO, adding an inline boost controller is better than adjusting the tired wastegate. Turbo spool up definitely was improved - time-wise.

JMH

__________________
Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)

I bought a boost gauge that measures vacuum too. Not only can I monitor the boost pressure but I can tap into any vacuum lines and test them as well.

Just an idea for you.

Danny

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1984 300SD Turbo Diesel 150,000 miles

OBK member #23

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(='.'=) This is Bunny. Copy and paste bunny into your
(")_(") signature to help him gain world domination

What did you end up getting and form where? There are so many boost gauges out there...I just want the simplest one for temporary measurement, not permanent install.

__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car

ALDA is used to tell the pump that there is most boost going on so it needs to put more fuel.

I bought a VDO one because it kinda matched the interior of my W115. But, I would just get something cheap, even Wal-Mart cheap. Most gauges are enclosed in a housing so nothing is exposed. As a result, you can literally tape it to your dash and be over with it until you are ready to find a proper gauge and a proper home for the said gauge. Also the gasoline type ones always have a vacuum side, so you get that covered for cheap. Now, what I would like to do someday is to find a switch that would allow me to select vacuum/pressure sources that feeds the gauge.

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Your TACH may have a loose connection...I was wondering why your mechanic would be dead one minute then flopping around the next... PanzerSD

i am inspired. i will replace my windsheild... with an intercooler. swedishK

for a source switch, a door lock controller would work.
John

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Before the overboost shutoff, should my boost ever be above the value I get at my 4000rpm reading?

Is the overboost shutoff supposed to only be a safety device, it is not suppoed to be used on a daily basis?

dd

__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car