Thanks for the heads-up on the VW pumps. I went to PnP today (we had really nice weather with snow coming tomorrow so I figured I better do it if I'm going to do it) and found a VW pump. Mine has an all aluminum body and should polish up really well.

I also took the bracket which is a royal pain to get out. It also holds the fuel pump (I guess) on the VW and I had to remove the whole fuel pump deal to get to the attaching bolts. I'll cut the bracket down to just hold the vacuum pump but that will require a lot of spot weld drilling. Pics to follow.

A couple of questions:
1) Is there a vacuum switch on a VW to turn it off and on? Mine won't need to run very often as it only needs enough slurp to shut the engine off but I'd like it to not run if not needed.

2) Which wire is ground? I got the pigtail and a little wire from the harness so I can make a plug-in connection but I don't know which wire is which.

Thanks

Dan

No vacuum switch on the VW pump. It is controlled by the ECU, which is why I was headed down the path of using a microcontroller to turn it on and off. If your's is only used for shutoff, that pump is kind of overkill. I'd just hook it directly to a momentary switch (and a relay) and use a pin-hole in the vacuum line to bleed off vacuum so you can restart right away.

The Red/Green-stripe wire is the positive and the Brown/Green-stripe wire is ground.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

I was thinking about this the other day, could you make a plate to go over the original mounting area for the OEM vacuum pump, but bring the "power" out through a shaft and have it drive something like a vacuum pump from a early 7.3 ford diesel? then maybe still use the electric for low vacuum, like at idle, if needed?

other than that, i would guess maybe going to a serpentine belt setup so you can stack all the stuff close together

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"NEW" 1984 300D TD needs some love

That would be beyond my engineering capabilities. Even the serpentine belt idea would require more than I'd be willing to put into it.

At first look, the electrical pump seemed elegant and interesting, but alas, the design of the VCV for the auto trans, just makes it impractical. For manual transmission cars, I think it is a real excellent option.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

I wish i could pick up a CHEAP parts car with a running motor, it would be interesting to play with some of these ideas on a car i don't have to drive several times a week, if not everyday, of course any good parts car would probably be nicer than the car i now have LOL.

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"NEW" 1984 300D TD needs some love

I like the idea of the blanking plate with bearing holding a shaft picking up power from the center of the dual cam drive. What is in the center? Can the dual cam wheel be removed without everything falling apart behind it? I think the dual cam wheel has to be removed to allow a flat plate to mount and use the original gasket and bolts.
VW has a engine driven rotary vane vacuum pump that could be mounted to the blanking plate. Some machining would be required. On second thought a bearing would not be required as the VW pump has a bearing at it's base. I think. There has to be a way to solve this problem, after all we have, on this board, a collection of the best automotive minds in the world.
I have my hat of to mack4 for the work he has done on this problem.
I purchased a Volvo Vacuum pump and a switch only to see the BUSTED sign.
Hart broken but not out of the game.

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

Problem is the VW rotary vane vacuum pump run the opposite direction to the 617 engine. Oh well.

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

hmmmm that sounds interesting, now can we build the alternator large enough to have an on board welder and the room to add a york compressor for on board air..... i so just need a unimog

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"NEW" 1984 300D TD needs some love

Question for Mach4. Is the VCB bleed so great that the pump would run constant at half or full throttle or close to it? You mentioned an average of around 8Hg. Would a reservoir help?
The Alternator mounted pump sounds great till the problem of getting oil to and draining back to the engine base has to be considered.
Is there any place that a venturi could operate. Would a minimal restriction in the intake ahead of the turbo charger be possible?

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

On the Turbo Diesel 300Dsthe space behind the Alternator is restricted.

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84 300D, 82 Volvo 244Gl Diesel

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.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

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

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

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.

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84 300D, 82 Volvo 244Gl Diesel

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

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica

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

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"NEW" 1984 300D TD needs some love