Losing vacuum as soon as engine stops ?

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mathuisella
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Losing vacuum as soon as engine stops ?

Post by mathuisella » Fri 24 Nov, 2017 3:14 pm

Hi everyone, well i'm sorting out the vacuum system and here's how it goes so far.


Engine on, all doors work as well as fuel cap and boot.

the moment i shut off the engine after parking, i lose all vacuum and the door won't lock, however if i wind the window down, step out of the car and lock the door with the drivers door button they all work perfectly, both to lock and unlock.

so, Engine on Vacuum all good

Engine off, no vacuum :/

any ideas ?

I've so far done 10 inches of mercury test on the tank in the boot, it holds pressure for minimum of 15 minutes.

I put vacuum pressure ( hand vacuum pump ) on the door lock and door unlock lines from the bonnet check valve and all seems okay, doors open and close.

tsharkey
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Re: Losing vacuum as soon as engine stops ?

Post by tsharkey » Fri 24 Nov, 2017 3:48 pm

The check valve in the engine bay runs 1 line to the vacuum tank up rear and the other to the lock / unlock valve in your Drivers door. The Lock \ Unlock valve in the drivers door shifts the vacuum between lock / unlock (green / red stripes). The reservoir up rear has vacuum in it to allow multiple lock / unlock as you loose a little vacuum when you switch between the 2 modes.

With the engine off, no new vacuum is being supplied. You say the engine is off and there is no lock / unlock anymore.

Either the check valve is kaput (it is leaking the vacuum back into the main line and being vented else where) or the lock / unlock valve in your door is leaking.

However ... You say
mathuisella wrote:
Fri 24 Nov, 2017 3:14 pm
the moment i shut off the engine after parking, i lose all vacuum and the door won't lock, however if i wind the window down, step out of the car and lock the door with the drivers door button they all work perfectly, both to lock and unlock.
Does that mean that when you are in the drivers seat and switch the engine off, you can not lock / unlock the doors anymore using the door button ? If so, the above applies.

If the door lock button works, but when you are outside the car, the key wont lock / unlock, then I suggest the Key mechanism is not linked to the door and your central locking is working A-OK.
W123 1981 300TD - Family Kid mover
W202 1998 C250D Factory OM605A Turbo - Partner's daily driver
W123 1982 300CD Retro fitted OM617A Turbo - Mine
W123 1984 300TD 5 Speed Manual, to teach the kids how to drive
W123 1982 300TD Factory OM617A Turbo (Hans) - Project
W123 1985 230TE - Brother's
W123 1985 300D - Sister in Law's
1962 S-Series Valiant (Tho Daimler & Chrysler divorced, still part of the extended family)

Past benzes
W114 1969 250CE - PO put in an M110 transplant and nearly sent me around the bend
W123 1981 300TD - "Matilda" - RIP hit front side & rear but left my brother + niece A-OK

Current Projects
Coupe restoration, Turbo Wagon freshen up

mathuisella
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Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Fri 24 Nov, 2017 4:49 pm

tsharkey wrote:
Fri 24 Nov, 2017 3:48 pm
The check valve in the engine bay runs 1 line to the vacuum tank up rear and the other to the lock / unlock valve in your Drivers door. The Lock \ Unlock valve in the drivers door shifts the vacuum between lock / unlock (green / red stripes). The reservoir up rear has vacuum in it to allow multiple lock / unlock as you loose a little vacuum when you switch between the 2 modes.

With the engine off, no new vacuum is being supplied. You say the engine is off and there is no lock / unlock anymore.

Either the check valve is kaput (it is leaking the vacuum back into the main line and being vented else where) or the lock / unlock valve in your door is leaking.

However ... You say
mathuisella wrote:
Fri 24 Nov, 2017 3:14 pm
the moment i shut off the engine after parking, i lose all vacuum and the door won't lock, however if i wind the window down, step out of the car and lock the door with the drivers door button they all work perfectly, both to lock and unlock.
Does that mean that when you are in the drivers seat and switch the engine off, you can not lock / unlock the doors anymore using the door button ? If so, the above applies.

If the door lock button works, but when you are outside the car, the key wont lock / unlock, then I suggest the Key mechanism is not linked to the door and your central locking is working A-OK.

sorry i should be more clear, everything works fine ( engine on ) whether i use the key from outside or i'm inside the car and use the drivers door button

engine off - no vacuum functions work.

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Bartman4800
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Re: Losing vacuum as soon as engine stops ?

Post by Bartman4800 » Fri 24 Nov, 2017 4:57 pm

Did you accidentally reverse a check valve? The one to the brake booster?

Easy to check, just suck on it...

Bart
1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
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2002 VW Passat V6 30V Station Wagon (SOLD - This car into a money pit)
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tsharkey
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Re: Losing vacuum as soon as engine stops ?

Post by tsharkey » Fri 24 Nov, 2017 5:01 pm

mathuisella wrote:
Fri 24 Nov, 2017 4:49 pm
engine off - no vacuum functions work.
The one in, 2 out Check Valve is not holding the vacuum - Your donor car has plenty.
W123 1981 300TD - Family Kid mover
W202 1998 C250D Factory OM605A Turbo - Partner's daily driver
W123 1982 300CD Retro fitted OM617A Turbo - Mine
W123 1984 300TD 5 Speed Manual, to teach the kids how to drive
W123 1982 300TD Factory OM617A Turbo (Hans) - Project
W123 1985 230TE - Brother's
W123 1985 300D - Sister in Law's
1962 S-Series Valiant (Tho Daimler & Chrysler divorced, still part of the extended family)

Past benzes
W114 1969 250CE - PO put in an M110 transplant and nearly sent me around the bend
W123 1981 300TD - "Matilda" - RIP hit front side & rear but left my brother + niece A-OK

Current Projects
Coupe restoration, Turbo Wagon freshen up

mathuisella
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Posts: 439
Joined: Sun 08 Jun, 2014 6:03 am
Model you own: w123
Location: Brisbane, North side.

Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Fri 24 Nov, 2017 5:44 pm

tsharkey wrote:
Fri 24 Nov, 2017 5:01 pm
mathuisella wrote:
Fri 24 Nov, 2017 4:49 pm
engine off - no vacuum functions work.
The one in, 2 out Check Valve is not holding the vacuum - Your donor car has plenty.
Looked in the doner car :/ it doesn't have central locking :O

seems like it was bottom of the barrel spec :/ no bells or whistles. 4 speed manual 240d no central locking, wind up windows, no sunroof or anything.

but at least the engine is nice :) and the body is 100% rust free


any ways.

i disconnected everything and used some silicon vacuum line to directly connect only the front passenger door to the drivers door.

1. i ran the engine for 30 seconds.

2. turned engine off

3. sat in drivers seat

4. pressed button down as i watched the front passenger, it locked, then unlocked.... cycled 8 times ( 8 locks, 8 unlocks ).

So it seems my problem is either in another connection or actuator :/

but i have to go to work now for the night, so we'll see how we go tomorrow.

cheers for the help so far guys :)

mathuisella
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Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Thu 30 Nov, 2017 5:01 pm

Looks like my rubber Y adapters ( factory) have come loose over time.

I went to the usual auto places, their vacuum stuff is so expensive, I'm just going to make my own on my 3d printer.
grgr.JPG
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Tony From West Oz
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Re: Losing vacuum as soon as engine stops ?

Post by Tony From West Oz » Thu 30 Nov, 2017 10:36 pm

Why not use reticulation trickle tube barbed Tees and Crosses for your multi-way connections. Use bog standard vacuum hose to connect the crosses or tees to the rigid vacuum lines.
I did this and it works fine on my W123 300CD Turbodiesel.
Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

'83 W123 300D 325000km (Wife's car Josephine - sold).
'84 W123 300D replaced good OM617 912 with OM617 952 and enjoyed having good acceleration for the first time since first driving a 300D in 2002 - became engine and trans donor for 300CD Turbodiesel conversion. Now parted out.
'86 W124 300D sold (Wife's old car - sold )
'85 W123 300CD, 275 000km (Fatmobile) rebuilt turbodiesel from previous Fatmobile transplanted into 280CE (SOLD)
'99 W202 C250 Turbodiesel (my darling Wife's car - Sold)
'98 W202 C250 Turbodiesel (my car - Sold)
'06 Ssanyong Musso Crew Cab 2WD Ute (OM662 diesel and Auto Transmission)

mathuisella
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Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Sat 02 Dec, 2017 4:16 pm

Tony From West Oz wrote:
Thu 30 Nov, 2017 10:36 pm
Why not use reticulation trickle tube barbed Tees and Crosses for your multi-way connections. Use bog standard vacuum hose to connect the crosses or tees to the rigid vacuum lines.
I did this and it works fine on my W123 300CD Turbodiesel.
That's pretty much what i'm doing, but the local places had nothing for me, wrong size or just too expensive.

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Tony From West Oz
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Re: Losing vacuum as soon as engine stops ?

Post by Tony From West Oz » Sat 02 Dec, 2017 4:32 pm

Have you got a big green shed near you? They usually have the barbed connectors and the trickle hose (right size, does not like the heat, but can be used to test the system) when you have it sorted, replace with vacuum hose. Have you tried ebay for the hose?
Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

'83 W123 300D 325000km (Wife's car Josephine - sold).
'84 W123 300D replaced good OM617 912 with OM617 952 and enjoyed having good acceleration for the first time since first driving a 300D in 2002 - became engine and trans donor for 300CD Turbodiesel conversion. Now parted out.
'86 W124 300D sold (Wife's old car - sold )
'85 W123 300CD, 275 000km (Fatmobile) rebuilt turbodiesel from previous Fatmobile transplanted into 280CE (SOLD)
'99 W202 C250 Turbodiesel (my darling Wife's car - Sold)
'98 W202 C250 Turbodiesel (my car - Sold)
'06 Ssanyong Musso Crew Cab 2WD Ute (OM662 diesel and Auto Transmission)

mathuisella
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Posts: 439
Joined: Sun 08 Jun, 2014 6:03 am
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Location: Brisbane, North side.

Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Sat 02 Dec, 2017 4:37 pm

Tony From West Oz wrote:
Sat 02 Dec, 2017 4:32 pm
Have you got a big green shed near you? They usually have the barbed connectors and the trickle hose (right size, does not like the heat, but can be used to test the system) when you have it sorted, replace with vacuum hose. Have you tried ebay for the hose?
the original vacuum hose lines in my car is good with no leaks. I'm just using solicon vacuum line over these connectors and the original vacuum hardline in the car, works well :)

mathuisella
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Location: Brisbane, North side.

Re: Losing vacuum as soon as engine stops ?

Post by mathuisella » Sat 02 Dec, 2017 11:58 pm

24321737_10212734492809983_394087445_o.jpg
Locking side works fine, seems the open side has a leak further down the line so to speak :)

will move towards the rubbers on the actuator and test those tomorrow.
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