Hi all,

I know that one valve must be the one for the vacuum lock system but which one is it, and what is the other for?

Thanks in advance.

i think the vac lock system usues a seperate vacuum system with a pump under the back seat. not engine vacuum related.

there are so many vacuum stuff under the hood i don't know what all they work...but a picture of the valve would help a lot.

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1987 300TDT
1981 VW MKI Caddy 1.6 diesel, waiting on engine swap
1983 D-50 Power Ram 4x4 "Mitsubishi" 2.3 turbo diesel
assorted gas powered crap and motorcycles

RIP: 1984 300TDT, 1982 300TDT, 1984 190D 2.2, 1992 300D 2.5, 1987 300TDT, 1982 Maxima LD28, 1983 Maxima LD28, Isuzu C223 P'ups X3, 1983 Holiday Rambler 6.2 Banks turbo diesel, 1984 Winnebago LeSharo 2.1 TD, 1985 Allegro 6.5

I would not be so sure his 78 240D has an Electric Vacuum Pump for his door looks.
I know my 300D has no Electric Vacuum Pump.

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84 300D, 82 Volvo 244Gl Diesel

You will need a Vacuum Diagram. When you see it you will note the Plastic Vacuum Tubings are color coded.
Another way to find out is to disconnect something and see what stops working.

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84 300D, 82 Volvo 244Gl Diesel

The yellow check valve is for the vacuum tank under the rear shelf. can see the tank above the fuel tank in the trunk.

One line goes into the valve, and two go out the rear. one to the tank and the other line to the drivers door for the door, fuel door and trunk locks. the tank is only for a vac supply for those locks when the engine is off.

My 80 240 only has one check valve.

there is no electric vac pump for the 240D, just the engine driven pump.


Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

^ Agreed, my 82 only had one as well.
78240D, can you attach pics?

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83 SD

84 CD

Here's what I mean....

Attached Thumbnails

 

Hmmmm, those are not stock check valves, I don't think, but should be okay.
Not sure what the red line goes to.
The green with yellow stripe on mine (my old one) is for the HVAC pods, that car has manual controls, but even the CCU has that green/yellow line. You'll also see a brown line, that branches off before, that goes to the ignition switch to provide vacuum to the shut off actuator when the key is turned off.
It's hard to tell, but is the brown/violet line hooked up to one of those? That doesn't make sense, as it usually goes to the shut off actuator from the ignition switch.
Maybe someone has swapped out different color lines, they are all the same size.

After a close look, my pic has the yellow check valve unplugged and the line that used to go to it is plugged off. The door locks don't work, but the car shuts off with the key.

Attached Thumbnails

 

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83 SD

84 CD

Don't know if this is relevant but on my 85SD the red line is the main climate control source going to the vacuum manifold in the console by the passenger's left leg. Mine was plugged in the engine compartment when I bought the car from FL. Significant changes were made in 85 & the 126 may not match yours but diagram is in the FSM.

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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.

Hi toomany MBZ,

My routing is obviously different than yours as my car is 6 years older than yours and not an auto. I've noticed that you have a 2-way check valve on the line that goes to your IP shut-off valve and mine does not. Could that be an issue for me?? The car shuts off fine it's just the door locks bleed off overnight.

That is not a two way check on the shut off valve at the end of the IP. the green thing is a vacuum dampener, abd the ivory colored thing is a vacuum control valve for the automatic transmission.

Yours being a 4-spd stick won`t have this.

I don`t know what your other check valve is either. and also the red line.

my 80 240D only has the yellow check valve. I think the 240 only has one vacuum pod for the heating system over on the right side. that would be what the green line is for.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

That car has a manual transmission.
The egr (78's didn't have one) has been bypassed, that's my guess why it even has a VCV, which is located just above the shut off actuator, not part of it. The connector with the green dashpot (vac damper) used to have a three way connector, now it just has a rubber hose from the main vac line.
Junkman, my SD has a red line also.

Attached Thumbnails

 

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83 SD

84 CD

you can confirm where the red line goes by pulling the passenger cover by the left leg. Connected in the engine bay & you have vacuum to the cabin climate coontrol manifold. Disconnected and you don't. Check the FSM for what vacuum pod works what.

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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.