Electrical Vacuum Pump Conversion Project - PeachParts Mercedes-Benz Forum

mach4 · #1 12-20-2013, 02:14 AM

I thought I would start a thread on a project to replace the engine driven vacuum pump on a 617 engine with an electrical pump.

There are a number of donor options and in doing the research on possibilities I created a list of possibilities.

2005-09 Audi A8 Quattro [8E0 927 317]
2004-06 VW Touareg [8E0 927 317]
2001-05 VW Passat [8E0 927 317]
1998-01 Audi A4/A6 [8E0 927 317]
1999-05 VW Jetta [1J0612181B and D]
1999-13 Volvo (most) [31317445]
1999-03 Saab 9-5 95 [46 46 220]
1994-99 Saab 9-3 900 9000 93 [46 46 220]
2011-12 Chevy Cruz [13343961] * (Pump appears ok, the problem is with a switch)

In an initial trip to the junk yard I found a VW pump but it was way too expensive. Today I found one for under $20 so I grabbed it. It came off a Passat. Here is what they look like.

I haven't ordered the vacuum switch yet but will shortly.

Right now I'm working on a design for a bracket and will get the pump mounted up before proceeding with the switch and relay.

The reason for the conversion is to eliminate the possibility for the engine driven pump to spill it's bearings and take the engine out.

There are at least two ways to control the pump. The first is with a controller. This is one that is used to control vacuum in a CNC machine environment.

It's $95 and is available on the BuildYourOwnCNC web site.

The other option is to use a switch and relay. I'm leaning toward this switch, which is available from EVParts

Pictures and progress to come.

strelnik · #2 12-20-2013, 08:26 AM

Quote:

Originally Posted by mach4

I thought I would start a thread on a project to replace the engine driven vacuum pump on a 617 engine with an electrical pump.

There are a number of donor options and in doing the research on possibilities I created a list of possibilities.

2005-09 Audi A8 Quattro [8E0 927 317]
2004-06 VW Touareg [8E0 927 317]
2001-05 VW Passat [8E0 927 317]
1998-01 Audi A4/A6 [8E0 927 317]
1999-05 VW Jetta [1J0612181B and D]
1999-13 Volvo (most) [31317445]
1999-03 Saab 9-5 95 [46 46 220]
1994-99 Saab 9-3 900 9000 93 [46 46 220]
2011-12 Chevy Cruz [13343961] * (Pump appears ok, the problem is with a switch)

In an initial trip to the junk yard I found a VW pump but it was way too expensive. Today I found one for under $20 so I grabbed it. It came off a Passat. Here is what they look like.

I haven't ordered the vacuum switch yet but will shortly.

Right now I'm working on a design for a bracket and will get the pump mounted up before proceeding with the switch and relay.

The reason for the conversion is to eliminate the possibility for the engine driven pump to spill it's bearings and take the engine out.

There are at least two ways to control the pump. The first is with a controller. This is one that is used to control vacuum in a CNC machine environment.

It's $95 and is available on the BuildYourOwnCNC web site.

The other option is to use a switch and relay. I'm leaning toward this switch, which is available from EVParts

Pictures and progress to come.

Great idea! I am looking at putting a power brake booster on a 170D or 180D which have none.
Am also looking at front disc brakes.

cho · #3 12-20-2013, 09:01 AM

.

another cool project I might consider...out of curiosity...why do we
need to control vacuum pump?

edit: is it just a on/off so it is not runnin' all the time...lot of folks converting to ecars use similar solutions fwiw..
also good switch and relay 24+18 bucks

thanks

cheers
ChO

.

Mölyapina · #4 12-20-2013, 09:17 AM

Cool! Methinks I'll be following your lead soon... the VP in my 'SD has 211k on it, so I need to replace it anyway.

OM617YOTA · #5 12-20-2013, 09:22 AM

Looking forward to how you mount your pump and how loud it is.

I have that exact pump solid mounted to the inner fender and by golly the whole county knows when it kicks on. It's loud and a different tone from the engine, can clearly be heard above the straight piped exhausted and the usual diesel clatter.

Dan Stokes · #6 12-20-2013, 09:29 AM

Thanks for this post. I've been kicking this idea around but you have a prettier solution than I've come up with. I'll only need it for shut off in the S-10 but I want it to be fool proof (given my level of "fool" that'll be tough).

What is that switch used on? Is it something I can scrounge at PnP? And is the VW pump Diesel-only or do lots of Vdubs have them?

Dan

pawoSD · #7 12-20-2013, 10:01 AM

Quote:

Originally Posted by Jooseppi Luna

Cool! Methinks I'll be following your lead soon... the VP in my 'SD has 211k on it, so I need to replace it anyway.

211k? The VP in my 300sd has 321k and works fine....I'm not worried. I had it off around 280k and it was in perfect shape inside. We have several 617's with original pumps and high miles with 0 issues.

I think there's a lot of VP paranoia around here, how many have actually had one fail? I replaced the one on my OM601 with a new engine mounted one because the original had 250k on it and was the exposed bearing variety. The new one has closed bearings and has been working great for 6k so far...

JB3 · #8 12-20-2013, 10:05 AM

where is this mounted in the VW application? does it have a special mount to cut down on noise?

I want one too

Smoker · #9 12-20-2013, 10:34 AM

There are some threads on this. I bought the Saab vacuum pump and two different vac cut off switches and a couple of relays. Used saab pump came with full mounting bracket assembly, including the rubber anti vibration bits.

It's on hold as I have the 300CD for sale, but since I have everything to do it I'm considering tossing it on the 240 tomorrow.

240's pump is fine I'm just looking at getting rid of that little bit of drag, and the potential bearing bomb. Since the 240 uses the pump only for brakes, it won't be running a lot. 300 uses it for climate, trans, seat backs, brakes....probably not the best first candidate.

mach4 · #10 12-20-2013, 11:01 AM

Quote:

Originally Posted by JB3

where is this mounted in the VW application? does it have a special mount to cut down on noise?

It's mounted on the drivers side toward the front right next to the ABS module. It has three rubber mounts for vibration isolation.

mach4 · #11 12-20-2013, 11:11 AM

Quote:

Originally Posted by Dan Stokes

Thanks for this post. I've been kicking this idea around but you have a prettier solution than I've come up with. I'll only need it for shut off in the S-10 but I want it to be fool proof (given my level of "fool" that'll be tough).

What is that switch used on? Is it something I can scrounge at PnP? And is the VW pump Diesel-only or do lots of Vdubs have them?

If you only need a shutoff solution, this is gross overkill. Use a vacuum pump from a Benz that is used for locking and unlocking. Dirt cheap readily available and low enough draw you shouldn't even need a relay.

There are no vacuum switches used on these pumps in their native installation. There is a vacuum sensor that is tied into the ECU that activates a relay when needed. Same exact operation as the electronic controller in post 1.

Smoker · #12 12-20-2013, 11:20 AM

For shutdown I'd guess the saab (and many other euro gasser) cruise control assist vacuum pump would be fine.

If someone wants I can yank one off a parts car and measure the vac.

mach4 · #13 12-20-2013, 11:35 AM

Quote:

Originally Posted by Smoker

For shutdown I'd guess the saab (and many other euro gasser) cruise control assist vacuum pump would be fine.

If someone wants I can yank one off a parts car and measure the vac.

It should also be fine for the lock/unlock function as well as climate control...just not brakes.

In fact there's no reason why someone couldn't set up a two circuit system with the brakes having its own pump and isolated from the majority of the potential leaks.

funola · #14 12-20-2013, 11:43 AM

Thanks for posting this. I'll be following your progress. Does the car you took the vac pump from have a vac reservoir and vac switch? Have you looked into whether removing the cam driven vac pump will cause any issues with what drives it (the timing device)?

Mölyapina · #15 12-20-2013, 11:46 AM

Quote:

Originally Posted by funola

Thanks for posting this. I'll be following your progress. Does the car you took the vac pump from have a vac reservoir and vac switch? Have you looked into whether removing the cam driven vac pump will cause any issues with what drives it (the timing device)?

Some folks over at STD have eliminated the vac pump, I think. I'll see if I can find that...