A place for more technical discussions. Please make sure you post in the correct section on the site, this way it keeps the site tidy AND ensures you get a more relevant answer.

Vacumm Hubs Just For a Change

More
14 Dec 2022 21:52 #246368 by DrRobin
Last year I thought I had a problem with the front hubs, my back wheels lost grip, so put it in 4WD and it didn’t seem much better. A few days after I jacked up the front and tested the vac hubs, both worked correctly.

All has been great until Saturday, it was cold and there was ice/snow, the back wheels spun when in reverse up a steep drive. I put it into 4WD and tried again, it was better, but I still felt the back wheels slip, I am pretty sure the front didn’t.

Both times the green light came on, but then it comes from pressure not hub position, I think?

Is it possible that that one or both hubs work sometimes and not others? If only one hub was engaging and not the other, would you still get good drive from that wheel or would it cause problems with the diff?

2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog

Please Log in or Create an account to join the conversation.

  • Lambert
  • Offline
  • Moderator
  • Moderator
    Registered
  • The quickest Jimny in Harrogate...(that I own)
More
15 Dec 2022 05:42 #246373 by Lambert
You need both hubs to engage to see useful drive otherwise you will just rotate the diff centre.

Temeraire (2018 quasar grey automatic)
One of the last 200ish of the gen3s, probably.
ADOS Attention Deficit Ooooh Shiny!

Please Log in or Create an account to join the conversation.

More
15 Dec 2022 10:12 #246381 by DrRobin
Thanks Lambert, that explains the Eddie's (original poster) experience, one drive shaft turned but with no power, the second not at all.

So if one hub vac line is blocked, you get a steady green light, but no 4WD. I suppose you could have one hub sticking in cold weather as well?

I might jack mine at the weekend and check operation.

2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog

Please Log in or Create an account to join the conversation.

More
15 Dec 2022 10:37 #246382 by auchenblae
I used the earth conductor from some twin and earth cable. If you have a compressor then the small air guns you get to use with them would do the job.

eddie

24 Swift Ultra ALLGRIP
16 SZ3 gone 25
07 JLX+ gone 16
99 JLX gone 07

Please Log in or Create an account to join the conversation.

More
15 Dec 2022 11:05 - 15 Dec 2022 11:08 #246385 by yakuza
Mine had no light at all from pushing the 4x4 button. At first when it failed a blink after 3-4 sec, but later in the week nothing.
Now with only minus 2 it is working fine again.
I suspect the actuator was frozen. I had been driving in deep powder snow and minus 15 so most likely packed underneath with snow.

If the actuator engage but the hubs not, the light will flash?
Or could it be the vacuum sensor at the intake manifold?
Or does it still flash the light if that one is out?

Norway 2005 Jimny M16A VVT, 235 BFG MT, 2" Trailmaster, ARB rear lck, 17%/87% high/low gears.
Last edit: 15 Dec 2022 11:08 by yakuza.

Please Log in or Create an account to join the conversation.

More
17 Dec 2022 11:20 #246424 by DrRobin
Just jacked the front of my Jimny and neither vac hubs are locking.

I get a solid green light on the dash and the transfer box is working as it locks the front drive shaft. The solenoids are clicking so my guess is it is something common, perhaps aa blocked pipe where it is common?

Apart from taking the vac hoses off each hub is there an easy way to tell if the vacuum is working or not, or possibly blow out both lines from the solenoid?

Robin

2020 blue SZ5 (one of the last to be registered in the UK)
Ex 2011 Blue Jimny SZ4
Northumberland Jimny Blog

Please Log in or Create an account to join the conversation.

Time to create page: 0.161 seconds
Joomla template by a4joomla
We use cookies to give you the best online experience. Please let us know if you agree to all of these cookies. Accepting the Cookies also accepts the Disclaimers for the website.