GQ TD42 vac pump Alternator recommendations?

Got a silvertop GQ td42 with vac pump on alt in a GU4

my auto8 alternator doesn't give any voltage until 1300 rpm
my original Hitachi one died and it used to charge at idle once I excited it
and revved it a little bit to wake it up but it too struggled with lights on,
demister and ac on

I'm looking at replacement alternators to buy and alot of the reviews
are saying the same thing ( crap voltage at idle )

What is with all the crappy alternators that don't charge at idle
or can't hold 14v with the AC fans and lights on?


Can anyone recommend a alternator brand that will charge at idle
with the AC fans and lights on?

Hey mate can confirm that mine is the same once she's had a good glow and the starters turned over lights on dash will just flicker . . Charges good once up and running but yeah not ideal. . Can you still get the Hitchi unit, other than that can't be much help sorry but keen also to find out. .

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the problem may not be the altenator . i have a zd myself ( vac pump separate from alt ) but have read discussions on the older models . it seems people upgrade the +ve power wire from alt to battery and the -ve from bat to engine to stop voltage loss . also there are a couple of wires that come plug into the alt . a solid white one and a white with red stripe . i think if i remember correctly the white with red stripe goes to instruments and the white goes to the power wire that goes from the alt to the battery but joins into the wire not far from the alt . both of these wires have had know common problems with breaks and dodge connections at the connector into the back of the alt . the connection and/or breaks need to be fixed in the white with red stripe wire . the solid white wire needs to be replaced and run all the way to the battery +ve terminal so that it will read the voltage properly so the alt will put out enough voltage . these wires don't need to be larger as one dosen't carry much load and the other is only a sensor wire .

Going to try source a 66m alternator pulley like this one
https://store.alternatorparts.com/pa...ternators.aspx

just having a hard time finding someone to ship it to australia

also going to do diode trick to see if this will help aswell

i had to go through this not so long ago,

i was in a rush for one i ended up buying a jaylec 80a with vac pump on the back from patrol apart.

Then i ran into the issue that it doesnt charge while idle witch is a pain when your in traffic and its raining, heater on, demister on ect the wiper motor is so slow haha

Ordered a UFI Alternator kit comes with a bosch 160amp alternator and some bits and bobs for the bracket spacer plug, will keep updates when it arrives

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Originally Posted by Bozanceroz

Ordered a UFI Alternator kit comes with a bosch 160amp alternator and some bits and bobs for the bracket spacer plug, will keep updates when it arrives

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160amps!!!! I want one of those!!! Have you got a link please

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Originally Posted by MudRunnerTD

160amps!!!! I want one of those!!! Have you got a link please

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I've spoke to Matthew from UFI about it check ur PM

Quote:

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Originally Posted by Bozanceroz

Ordered a UFI Alternator kit comes with a bosch 160amp alternator and some bits and bobs for the bracket spacer plug, will keep updates when it arrives

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going to be ordering a vacuum gauge tester tool and seeing how much vacuum i pull at idle and at 1000rpm and 2000-3000 rpm
then im going to be installing a hella up28 vacuum pump off a ve/vf commodore with a gq vacuum canister setup and test the vacuum again

ill be doing this after my trip hopefully

FWIW: Scored an insane 180A aftermarket built GQTD (yes with vac) off an Ebay Legend years ago. Was only advertising for a short time out there but Crikey did the 6hp High Mount (12v :-( haul hard for 1 maybe 2 trips.
Them Diodey thingies in the back as @PeeBee once kindly tought me also need to be upgraded to handle the pimped well above the back ends capabilities [emoji23][emoji23]


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FWIW-2: You’ll struggle to purchase (with warranty) anything above + 20% from OEM easy in/out swap [emoji51]
Please prove me longevity wrong, want 2 meself [emoji120][emoji120]

EDIT: “Currently” 2022 3/4 through [emoji23]

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https://alternatorparts.com/quicktif...rectifier.html

Here is the life saver for alternators that get taxed from running beyond their service limits. Multiple high capacity diodes, bullet proof - I have gone the 400amp unit and very happy. The unit is rated for a 400amp charge over extended time - you can use it on a lower capacity alternator and get the full amps out of the alternator for extended period, like winching. You only get out what you put in, so if alternator rated at 150amps, it will spread the load across many banks of diodes and you get 150amps but no heat which is the killer of the alternator. I have pushed a 300amp alternator for maybe 30 minute on a winch pull with some resting but the battery kept up. Worth the money.

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Originally Posted by PeeBee

https://alternatorparts.com/quicktif...rectifier.html

Here is the life saver for alternators that get taxed from running beyond their service limits. Multiple high capacity diodes, bullet proof - I have gone the 400amp unit and very happy. The unit is rated for a 400amp charge over extended time - you can use it on a lower capacity alternator and get the full amps out of the alternator for extended period, like winching. You only get out what you put in, so if alternator rated at 150amps, it will spread the load across many banks of diodes and you get 150amps but no heat which is the killer of the alternator. I have pushed a 300amp alternator for maybe 30 minute on a winch pull with some resting but the battery kept up. Worth the money.

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what type of 300 amp alternator are we talking about here

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Originally Posted by Bozanceroz

what type of 300 amp alternator are we talking about here

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Its a direct replacement for the 14V alternator supplied with the Chev engine conversion I have. It does not have a vac pump on the back like the nissan alternator. The focus is to reduce the temperature of the diodes so you can get more capacity out of your existing alternator. Have you looked at the link?

now currently using a UFI alternator kit
160amp bosch alternator
with a custom bracket
machined spacer and longer bolt

for vacuum ive replaced my vacuum system with electric one

using a Hella UP5X vacuum pump and a vacuum switch thats adjustable from element14
also using a canister from my old gq and the gq 1 way check valve

Electric vacuum pump (Hella UP5X) # 8TG 012 377-701
https://www.hella.com/microsite-elec...-pump-118.html

vacuum switch #PSF109S-81-330
https://au.element14.com/multicomp-p...o/dp/173468601

not sure what I should have the vacuum set at on the switch, currently have it at 22.5 in Hg
the old alternator I had would do 18-19 in Hg at Idle and max at 25 in Hg at about 2k - 2.5k rpm

I have still yet to upgrade the wiring to the battery feed and grounds in my S4, im going to do the big 3 upgrade

I was going to use a UP28 but I determined it not suitable for my application reason being it is more of an assist vacuum pump.
Its more for a engine that can produce vacuum but not enough of it or like a backup bump.

Attachment 85920

The UP5X or UP5.0 can be used as a standalone
the up5x has more than double the service life of the up28 and gets to the desired vacuum nearly twice as fast

Attachment 85921

I was trying to source a UP30 or UP32 from wreckers and just thought to myself I'll just get a brand new one and the best one hella sells

Attachment 85922

I got my vacuum pump for $325 delivered from the UK to Australia

That's very interesting mate, thanks for sharing.
When you say you were trying to source it from a wrecker, what sort of car or truck come with such electric vac pump?

I've been looking at the UP28 because I only need it for my vacuum diff lock now that I have hydroboosted brakes. I still have the vacuum pump on the alternator but adding the UP28 would allow me to fit a normal alternator if required.
I also looked at secondhand Holden Commodore units with switch that pop up occasionally on Marketplace but you can never know the history of them.

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Originally Posted by BrazilianY60

That's very interesting mate, thanks for sharing.
When you say you were trying to source it from a wrecker, what sort of car or truck come with such electric vac pump?

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UP32 OEM CARS
going off this list on ebay for suitable cars for this listed up32 pump
https://www.ebay.com.au/itm/155010652854

press cars on this page to see the models it comes with
https://www.trodo.com/vacuum-pump-br...tg-009-570-321

vw touareg (2011 - 2018)
porsche cayenne (2011- 2014)
porsche panamera (2011- 2013)

I asked some people wrecking on FB marketplace and they were like where is it located?
I couldn't be bothered looking up diagrams of where it was located in the car to tell them.
Then I thought about owning something that is already around 10 years old and the wear
and tear that it could possibly already have.

I then decided to get a brand new one and better one aswell, if UP28 pumps are going for
$100-140ish I guess a second hand UP32 could be around? $150-200+, no idea tho I never
found out how much they're going for second hand

Quote:

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Originally Posted by jff45

I've been looking at the UP28 because I only need it for my vacuum diff lock now that I have hydroboosted brakes. I still have the vacuum pump on the alternator but adding the UP28 would allow me to fit a normal alternator if required.
I also looked at secondhand Holden Commodore units with switch that pop up occasionally on Marketplace but you can never know the history of them.

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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


the switch that I've used is adjustable and you can adjust (with small alen key) how much vacuum to go up to till it turns off
you shouldn't have the UP28 running constantly its only rated for 600 hours life

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

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

Attachment 85934

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

Attachment 85935


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

Quote:

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Originally Posted by Bozanceroz

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

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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...
Attachment 85936

Still don´t know from which application he is taking this switch.
Attachment 85937

Quote:

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Originally Posted by BrazilianY60

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...
Attachment 85936

Still don´t know from which application he is taking this switch.
Attachment 85937

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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

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.

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.

Found it. It is from a GM applicaton.

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

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.