I need to install an electric vacuum pump to operate my brake booster in the W123. I have no need for the other systems that once ran on vacuum.

Just wondering what model pump others have used. Perhaps theres one that just threads on to the factory line from the booster vs something I need to fabricate. Where did you mount your electric pump?

Thanks!

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Old Blue - 83 240D 6 speed manual trans, OM648
Green Machine - 2001 Europa G500
87 300SDL Bought on Peachparts. Low-ish miles..?

Family Truckster - 2012 VW Touareg TDI

Patchouli Wagon - 2004 E500 - SOLD
333k mile 97 BMW 750il V12. - SOLD
The Californian - 85 300TD - SOLD
Daily Super Sedan - 03 Audi S8 -SOLD

If you have an automatic transmission, you also need vacuum for that.

The nutshell issue is that the vacuum system for the transmission always has a vacuum bleed/leak. That can mean a vacuum pump runs all the time the vehicle is running.

There are a few threads on it. I only tested it to see if it worked. There is at least one other thread.

Add On Electric Vacuum Pump for W123 Locking System

If you go to summit racing, you will see what vacuum pumps are used by what in the past been called hotrodders use.

Go to eBay and you can see all kinds of vacuum pumps. Note that electric vehicles that use vacuum brake boosters have vacuum pumps that are made for that job.

For someone making their own system there is a need for a turn on/turn off switch that goes on when the vacuum drops to X level. That means you need the vacuum switch and a relay.

I bought some check valves like the picture ones on eBay and is have some eBay ones that are all plastic. They are also made for use in fuel lines.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

Note that this is in conjunction with the normal vacuum pump that comes on my Volvo Diesel.
The Volvo Diesel Vacuum Pump has too low of a vacuum. After 3 brake pumps I run out of vacuum.

I wired installed an electric vacuum pump to the brake light switch. When you step on the brakes the vacuum pump goes on. That has worked fine. Not it has a manual transmission.

If you W123 had a manual transmission, and you installed an electric vacuum pump to turn on with you stepped on the brake i don't know if that would build up enough vacuum fast enough for the brakes to function normally.

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84 300D, 82 Volvo 244Gl Diesel

I was hoping for a response like: use this pump X out of vehicle Y.

I have an OM648 in this car which does not have a vacuum pump. I have a 6 speed manual transmission behind it. I also have manual climate control and deleted the A/C. The automatic locks have never worked in this car and I don't plan to fix them. I just need to have my brakes boosted with vacuum. This car is quite peppy with the OM648 and I need to be able to slow it down . Right now I press on the brakes really hard which is not so safe.

I've seen some universal hot rod type pumps for ~$400 but I really didn't want to spend that much then wire in and build a custom mount and take up 1/4 of my clean engine bay. I probably wouldn't spend that when for a bit more I could go hydroboost. I've already had custom power steering lines created....

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Old Blue - 83 240D 6 speed manual trans, OM648
Green Machine - 2001 Europa G500
87 300SDL Bought on Peachparts. Low-ish miles..?

Family Truckster - 2012 VW Touareg TDI

Patchouli Wagon - 2004 E500 - SOLD
333k mile 97 BMW 750il V12. - SOLD
The Californian - 85 300TD - SOLD
Daily Super Sedan - 03 Audi S8 -SOLD

I can give you links to my research , it may take some looking around the internet to see what you like . This is a YouTube link , britannica restorations Ltd . , the video content is the following . Experiment with electric vacuum pump 300tdi . A wealth of good knowledge , gave me a better understanding of the system .

I would contact Leed , the vane style vacuum pumps are superior in long life and quietness . Summit sells them

An engineer where I used to work was into electric vehicle conversion. Those guys deal with this problem on every conversion where they need to handle their booster. I’d do a search on that and see what they come up with.

The guy at work used a diaphragm pump from KNF Neuberg. I think he chose it because it was a similar pump used in our product line of industrial test equipment and he could get free diaphragms from the stockroom. Although it was a high quality pump, the duty cycle in our app was quite high 24/7 and it needed service every three years. The diaphragms cracked like a clock.

I’ve been following your build thread. Really cool stuff you’re building.

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79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles

Have you asked h3ffe what he's using?

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1981 240D 4sp manual. Ivory White.

This is a whole kit on ebay: 28146Electric Vacuum Pump Kit For Brake Booster Vacuum Pump Electric Vacuum Pump $198.00 shipping US $15.00 SpeedPAK Standard (that means it is coming direct from China and will take as much as a month)

Go to ebay and see it.

There is also a similar kit on ebay for $155 Electric Vacuum Pump Kit Mounting Hardware for Brake Booster 12 Volt 18 to 22 looks like free shipping

They both seem to be this vacuum pump- SSBC 28146 Electric Vacuum Brake Pump Kit Brake Booster. Go to Summit Racing and see if this is the same kit they are selling.

Here is the installation instructions for the SBC V Pump:
https://static.summitracing.com/global/images/instructions/ssb-28146_au.pdf


Concerning the plug and play. No on I know has done that.

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84 300D, 82 Volvo 244Gl Diesel

https://www.youtube.com/results?search_query=Experiment+with+electric+vacuum+pump+300tdi

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ASE Master Mechanic
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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.
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Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

https://www.boldegoist.com/

Subscribed just in case I ever try this solution .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Reading through some current posts and saw a link to this older post of mine in a thread started by vwnate1. I wanted to come back and update this with greater detail.

I ended up mounting a vacuum pump from a 2010-15 Camaro where my AC dryer used to sit. It can be seen in the lower left of the photo.


The setup is vacuum pump > check valve > pressure sensor > brake booster. I used AN line to run from the pump over to the booster. I'm not using any other vacuum in my car. No auto locks, and I have manual climate control.

Don't use crap pressure sensors from China. The ones that are on amazon for $28. They're all trash I tried 2 or 3 of them. I'm now running one of these in the link below to sense vacuum and send ground to my relay which triggers the pump. https://www.whitmancontrols.com/catalogsearch/result/?q=P88V-1-K5TB

Honestly the system is not as good as the mechanical vac pump but works. Some times at first press the pedal is hard but then if I press it again it's fine. I could probably adjust the vacuum sensor but haven't messed with it much. This car is not my daily driver.

__________________
--------------------------------------------
Old Blue - 83 240D 6 speed manual trans, OM648
Green Machine - 2001 Europa G500
87 300SDL Bought on Peachparts. Low-ish miles..?

Family Truckster - 2012 VW Touareg TDI

Patchouli Wagon - 2004 E500 - SOLD
333k mile 97 BMW 750il V12. - SOLD
The Californian - 85 300TD - SOLD
Daily Super Sedan - 03 Audi S8 -SOLD

Thank you ! .

The switches have multiple choices but only one image ~ do you know the difference ? .

TIA,

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

You can answer a question for me. When I tested a similar vacuum pump. I found that the steel end cover got really hot. What I want to know is if that is normal for that type of V pump.

I have a Volvo diesel that has a weak vacuum pump. If you pump the brakes say 2-3 times even with a vacuum reservoir you get that hard pedal. What I did is with a relay I wired up a electric vacuum pump to the brake pedal switch so a soon as I step on the brake pedal the vacuum pump would turn on.
You can also do that with your present system so that the vacuum pump turns on as soon as you step on the brake pedal and the vacuum does not have to fall set off the sensor. Just use another relay and run another relay and set up another circuit to power the V pump and use it together with the vacuum sensor.

Perhaps a larger vacuum reservoir would also work.

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84 300D, 82 Volvo 244Gl Diesel

My car has a mechanical W220 OM648 vac pump. I believe OM613 cars also used this setup.

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1983 300D Midnight Blue
4 speed, W115 intake mani, non-EGR exhaust mani, KKK K26, 3 pc Euro bumpers, Lo-spec Euro headlights, AL129X, hubcaps, custom A/C

1987 300TD Smoke Silver
Euro headlights, thermostat relocation, coolant bypass mod, rebuilt Becker + Jehnert + Helix audio, OEM Oris roof boxes and surfboard racks, Euro towbar

1983 300TD Reed (Moss) Green / Dark Olive MB Tex Euro spec

1983 300TD Silver Blue / Blue cloth Euro spec, OM648 and 722.6, 15" hubcaps, W126 S2 brakes