Electrical Vacuum Pump Conversion Project - Page 9 - PeachParts Mercedes-Benz Forum

Dan Stokes · #**121** 01-30-2014, 02:50 PM

Oops - guess I missed that tasty tidbit of info! Yep, that's the little jewel. I now have all the parts identified and most on the way to make my race-only system work. I'll pick up a box and mount all the little stuff (switch, relay, etc) in there to make it more sano.

Dan

pgringo · #**122** 01-30-2014, 04:40 PM

Quote:

Originally Posted by Dan Stokes

I think I made a significant find for this conversion. There's a company called EV parts that offers a vacuum switch designed for this type of application. I found them online and they're EV as in Electric Vehicle Parts. Inc. - they specialize in bits for EV builders. The woman on the phone said that they have these built with the right parameters for automotive use. You'll need to run the pump thru a relay but that's not a big deal.

EDIT: I just double checked and the vacuum setting is adjustable but comes from the factory at 18-22"Hg. As I understand it, this means that the pump will switch on at 18" and off at 22". I'll crank mine down a little as I don't need that much just for shut-off.

The bottom line is you fork over about $40 (with shipping) and you get a device that will switch the pump off and on as needed to maintain a pre-set vacuum level.

Mine's on the way

Dan

BUT, are the off and on adjustable seperately? that would make a huge huge difference.

mach4 · #**123** 01-30-2014, 05:23 PM

Quote:

Originally Posted by pgringo

BUT, are the off and on adjustable seperately? that would make a huge huge difference.

According to the site "The hysteresis is 15% to 20%" so there is no real need to have an upper and lower set point for this application. Now, if the hysteresis was set at 1% or at 50% (to consider some extremes) that would be a problem.

OM617YOTA · #**124** 01-30-2014, 08:30 PM

Dang.

Swap in a new electronically controlled transmission? There are adapters for the 617 to bolt them to GM transmissions, and a 700r4 would do well and I think it even has torque converter lockup.

Getting awfully expensive, vs. a $250 mechanical pump every 8 years.

The Gears · #**125** 02-02-2014, 10:24 PM

Question for Mach4. When the pump heats up is it the motor or the pump body that gets hot? Ant idea of the motor RPM?
Thanks

Diesel911 · #**126** 02-02-2014, 11:34 PM

Quote:

Originally Posted by The Gears

Question for Mach4. When the pump heats up is it the motor or the pump body that gets hot? Ant idea of the motor RPM?
Thanks

If you are speaking of the Hella type Vacuum Pump pictured in Mach4's first post; on mine it was clearly the Pump end not the Motor that got hottest.
I don't recall anthing on the outside of the Motor to indicate the speed and I don't see any way to measure that.

yvairguy · #**127** 02-02-2014, 11:46 PM

anybody try a thomas continuous duty pump and give it a reservoir to give it some cycle time good measure?

mach4 · #**128** 02-03-2014, 01:10 AM

Quote:

Originally Posted by The Gears

Question for Mach4. When the pump heats up is it the motor or the pump body that gets hot? Ant idea of the motor RPM?
Thanks

Never ran it enough to get hot. No idea on motor RPM...very similar to Bosch fuel pump is my qualitative assessment.

yvairguy · #**129** 02-03-2014, 02:37 AM

Thomas Series 107 Diaphragm Vacuum Pump Compressor 12VDC | eBay

continuous duty, same company that makes the compressors for the O2 concentrators, i think you can also get that set up(twin compressors/vacuum pumps) would also be able to add on board air.

strelnik · #**130** 02-03-2014, 09:10 AM

Quote:

Originally Posted by yvairguy

Thomas Series 107 Diaphragm Vacuum Pump Compressor 12VDC | eBay

continuous duty, same company that makes the compressors for the O2 concentrators, i think you can also get that set up(twin compressors/vacuum pumps) would also be able to add on board air.

This is a great thread for a variety of reasons! Am concerned about one thing.

How will all of them them respond to super cold or hot weather?

I ask the question, living in the Midwest.

Here diaphragm compressors die in the -5 daily weather and so the little pumpers have to be kept insoide overnight.

What about the vacuum pumps?

It would seem the vane dels with lubricant and seals would be ok, but are there durability specs for the others?

What do we know about the VW components? Any info on the Net re: durability/failures?

Just asking before I consider buying..

yvairguy · #**131** 02-03-2014, 11:10 AM

Quote:

Originally Posted by strelnik

This is a great thread for a variety of reasons! Am concerned about one thing.

How will all of them them respond to super cold or hot weather?

I ask the question, living in the Midwest.

Here diaphragm compressors die in the -5 daily weather and so the little pumpers have to be kept insoide overnight.

What about the vacuum pumps?

It would seem the vane dels with lubricant and seals would be ok, but are there durability specs for the others?

What do we know about the VW components? Any info on the Net re: durability/failures?

Just asking before I consider buying..

Check out thomas website they have all that info, plus will help source the right pump

Diesel911 · #**132** 02-03-2014, 12:38 PM

Quote:

Originally Posted by strelnik

This is a great thread for a variety of reasons! Am concerned about one thing.

How will all of them them respond to super cold or hot weather?

I ask the question, living in the Midwest.

Here diaphragm compressors die in the -5 daily weather and so the little pumpers have to be kept insoide overnight.

What about the vacuum pumps?

It would seem the vane dels with lubricant and seals would be ok, but are there durability specs for the others?

What do we know about the VW components? Any info on the Net re: durability/failures?

Just asking before I consider buying..

I think your question is far advanced of what people have done at this point.
I have not read yet of anyone having a complete working system in daily use.
I don't hang out there because you need to pay to be a Member but the Mercedes Benz Club of America could also have some read info.

EricB1970 · #**133** 04-16-2014, 07:55 PM

Quote:

Originally Posted by mach4

The myth that it's possible to use an electrical vacuum pump on an automatic 617 vehicle is officially...

Incorrect. I have had in use for a couple of months now a VW pump like show in the pictures posted here on my '83 300D and it works perfectly, shuts off at 18" of vacuum, and only comes on when needed. THE trick is, use a vacuum check valve between the pump and the vac switch, and don't use it for the trans. The VW pump doesn't appear to have a built in check valve, so when it shuts off it bleeds vacuum, so it kicks back on, then shuts off, bleeds off vacuum, turns on, over and over. This is the reason along with trying to use it for the trans is what's causing the issues everyone is having.

For the trans, I bought a Dorman vacuum pump from a 2002 or so Ford Super Duty cruise control. This only supplies vaccum to the trans, and after a 4 hour trip of it running continuously last weekend it still didn't get too hot to touch. I don't use a reservoir for the trans, just a direct line from the pump to the trans. The VW pump doesn't work nearly as hard and didn't get hot at all on the 4 hour continuous drive.
Along the same lines, I gutted a spare mechanical pump and used it as a block off plate, with no apparent ill effects.

resago2000 · #**134** 09-24-2020, 05:17 PM

resurrecting an old thread.
what if you get a 3 port gas solenoid, relay,and micro-switch.
run vacuum to the normally connected ports on the solenoid. have the micro-switch activated at some throttle position that then makes the solenoid vent the vacuum in the transline out the third port, while closing the vacuum source port so the pump doesn't run all the time.

EricB1970 · #**135** 09-26-2020, 03:27 AM

Might work. I converted my '83 to a manual transmission this year and haven't looked back. Best thing I've ever done to the car.