I called the dealer, but they were no help. (Maybe I didn't explain myself very good.)

I searched for a while on this site, but didn't see exactly what I'm looking for.

Here is my question...

84 300D (turbo).

There is a hard, plastic, clear (OK, not so clear) vacuum hose that runs from the back of the intake manifold to a switchover valve (according to Haynes). The valve is located on the firewall, driver side. Haynes calls this tube a "delivery line from intake manifold" and is part of the turbocharger system. (Another hose goes from the switchover valve to the aneroid compensator in the IP.)

Can I replace this hose with regular rubber vacuum hose, or should I get special?

If I need special hoses, is the dealer the best source or are there other sources?

Also my hose seems to have black stuff all in it. I don't think that is good, but it almost looks so perfect that you could almost convince me that it's supposed to be there.

Anyway, I have to ask... should it have anything in it or should it be clear and open?

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1984 300D 398K-daily driver
1998 Honda Accord 102K -wife's daily driver
1991 Volvo 740 289K
2000 Toyota Corolla 143K

I believe this stuff is polypropylene rigid tubing. The dealer has it, you just need to ask for boost signal line. Probably expensive.

It is also available from Performance Analysis in Oak Ridge, TN along with door lock vac diaphrams, rebuild climate control units, etc.

You cannot use plain vac line because it is under pressure, not vac, and the expansion of the rubber hose would be a problem.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

It (clear line) should not have anything in it, should be clear and open! This tubing passes a boost signal thru the valve on the firewall to the ALDA and allows it to increase fuel flow of the IP in proportion to boost level. The intake is also likely to be covered with this crud. Comes from the EGR valve which should be blanked off or at least have the vac tubing plugged or removed. Clean all of the crud from 'banjo' bolt at intake all the way over to the ALDA, if it goes that far.

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1961 190Db retired
1968 220D/8 325,000
1983 300D 164,150

Ah ha!

(Light bulb goes off....)

The turbo has the entire intake manifold under pressure, right?

Can you tell I'm not used to working with turbo engines too much?

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1984 300D 398K-daily driver
1998 Honda Accord 102K -wife's daily driver
1991 Volvo 740 289K
2000 Toyota Corolla 143K

Thanks for all the info.

Line needs to be clear. Clean it from one end to the other.

By the way....I've got the EGR block kit (for testing purposes) just this week. Got it from... ummmm.... can't remember his name, but he was posting the kit a few weeks back on this board.

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1984 300D 398K-daily driver
1998 Honda Accord 102K -wife's daily driver
1991 Volvo 740 289K
2000 Toyota Corolla 143K

the alda pressure line. look it up on **************.com thats the only place i could find it.

__________________
have no worries.....President Obama swears "If you like your gun, you can keep it

Me.

bought turbo boost line with one banjo fitting from mb dealer last year. less than seven dollars.

don

I replaced both the banjo fitting line AND the signal line from the switchover valve to the IP. Total was about $15.00 AND it came with a new banjo fitting. Made in Germany. You'll also need to clean out your switchover valve when you install the new lines, since they have the black soot in them. Most likely also plugged.

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84 300DT Puke Yellow. Totalled after 438,000
84 300DT Orient Red. 169,000 (actual mileage may vary)
2002 Explorer EB (wife's)

Courtesy of Gsxr:

Vacuum line ("plastic" Tecalan pipe, 4mm OD, 1mm ID)
=====================================================
000-158-14-35 - Transparent (sort of white)
000-158-89-35 - Transparent with red stripe
000-158-91-35 - Transparent with blue stripe
000-997-39-52 - Brown
001-997-81-52 - Black
116-276-06-30 - Black with white lettering
123-276-16-30 - Black with red stripe

Just order it by p/n. The dealer can be a moron.

Here's my clear vaccuum line.....

http://pg.photos.yahoo.com/ph/captainwilliammccue/detail?.dir=6188&.dnm=16d9.jpg


Got as much as you want of the blue line. Goes great with my china blue wagon

Check your local plumbing supply.
They should have several choices that are better than OEM.

__________________
ASE Master Mechanic
https://whunter.carrd.co/

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
2003 Volvo V70

https://www.boldegoist.com/

When you going to upgrade that primer pump.

Forget to mention I like the way you did the lights.

Also if you had a feather up your a$$ and I had your car we would both be tickled. :p

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'10 Chrysler T&C Stow-N-Go White. Grandpa's ride.

'13 Chrysler 200 Touring Candy Red. Grandma's ride.

Age and cunning will always over come youth and vigor.

I've wanted to replace the boost signal line between the banjo bolt to the switchover valve to the alda.Mine is very old and brittle. I searched locally for a suitable replacement and was finally directed to the Freightliner shop.This morning I bought 6 feet of air brake line for a buck and a half.Heat resistant .25 inch black tubing.

psfred, do you know their phone number? I could not find their web site. Tnx.