GQ TD42 vac pump Alternator recommendations?

[Bozanceroz]

I credit alot of my research to this post by "cushjbc" on benzworld.org forum

https://www.benzworld.org/threads/he...pumps.3041049/

Vacuum Switch Schematic (1).pdf

Im including how I wired mine expect I used thicker cabling for power and ground for the 30 and 87 wires

f3fb74cf5291be47ab05be5f2daeb99d.png


If anyone does buy the PSF109S-81-330 Vacuum pressure switch
note that it uses the smaller blade connectors, I bought these 4.8mm female blade connectors and crushed them with pliers a bit to fit the 4.7mm terminal

[BrazilianY60]

the switch with the commodores is not what you want for the patrol
its a 5v switch and operates between 0.4-4.8v
Attachment 85933

I see your point. This one is a sensor and the voltage corresponds to the reading and then a control unit takes decisions based on the reading.

For this application we need just a vac switch, no need to report a reading.

After reading this posts of yours, I started looking around here (Brazil) and found a bloke selling online new UP28 with the vac switch for "alternator vac pump replacement/conversion" on diesels. The price of the UP28 is actually very good. The price of the switch he sells is more then the UP28 itself. I am trying to find a vac switch that could be used for this at a lower price.

This is how he is selling his stuff. Pretty "rough"...

Here the UP28 is used on VWs like Jetta, Golf, Audi...
VAC Brake UP28 Hella pump.jpg

Still don´t know from which application he is taking this switch.
VAC Brake vac switch.jpg

[Bozanceroz]

I see your point. This one is a sensor and the voltage corresponds to the reading and then a control unit takes decisions based on the reading.

For this application we need just a vac switch, no need to report a reading.

After reading this posts of yours, I started looking around here (Brazil) and found a bloke selling online new UP28 with the vac switch for "alternator vac pump replacement/conversion" on diesels. The price of the UP28 is actually very good. The price of the switch he sells is more then the UP28 itself. I am trying to find a vac switch that could be used for this at a lower price.

This is how he is selling his stuff. Pretty "rough"...

Here the UP28 is used on VWs like Jetta, Golf, Audi...
VAC Brake UP28 Hella pump.jpg

Still don´t know from which application he is taking this switch.
VAC Brake vac switch.jpg

looks a bit similar to a volvo switch that ive seen on youtube, but is heaps different in design

there is also a version of the UP28 which is a 3 pin instead of a 2 pin
at the bottom of page 4 u can see the differences
https://www.hella.com/resources-soe/...69076a_AM0.pdf

that one looks like the one with the relay box
im not sure if thats more suited for ECM controlled cars

[BrazilianY60]

This one being sold here is definitely the 3 pin version. The third one is a signal that turns on the pump when grounded. So, the vac switch is only a NC switch that disconnects its two terminals apart once a certain vac level is achieved. See on his rudimentary arrangement that the ground that goes to the pump also goes to the switch and the thinner control wire for the pump goes to the other pin of the switch.

This pump has a relay incorporated basically so other than a fuse, you would connect it straight to the battery, and the relay action is controlled by the third pin once earthed.

[BrazilianY60]

The switch takes no power, it just opens two NC contacts. Possibly all mechanical with a diaphragm opposed to a spring (to provide for the level of vac required) pulling a rod that opens the NC contacts.

[BrazilianY60]

Found it. It is from a GM applicaton.

OEM:13251900
Fitment : For Chevrolet Malibu Cruze Buick Regal LaCrosse

[jff45]

A UP28 wouldn't run much at all in my intended application. The vacuum in my Patrol is now only needed for the diff lock and the idle up when AC is switched on.