Monday, 28 October 2019

Another Delivery

Fastway Snailway finally delivered my package…… it only took 11 days!  Meanwhile Jan receive a package from the UK in 3 days.  Well this is Australia……

I’d been browsing eBay when I noticed a breather kit at the very reasonable price of $40.  What did I get for my money?


  • Steel mounting bracket for four breather.  The photo on eBay showed the bracket as anodized black but I’m not complaining
  • A length of plastic tube which will need to be cut for the four breathers
  • Some zip ties to secure the tube under the vehicle
  • Six straight tube connectors
  • Two elbow connectors
  • Four filter/breathers
  • Three mounting screws for the bracket.

The Isuzu 4x4 has four gearboxes

  • Front and rear differentials
  • Manual 6 speed gearbox
  • Hi/Lo range gearbox.

Why fit a breather kit?  The simple explanation is each gearbox is partially filled with oil and the rest of the void is full of air.  The gearboxes are sealed which prevents the oil leaking.  However when the vehicle is moving the oil and air gets hot.  This means it expands and if there wasn’t a vent (breather) the seal might burst. 

My 4x4 already has a breather fitted to each gearbox and the vehicle can wade through water up to 600mm deep.  The potential problem is when the hot gearbox is immersed in water it rapidly cools causing a vacuum inside.  Instead of the breather exhausting ait it’s sucking.  There is a potential for water to be sucked into the gearbox.  Water and oil in a gearbox can lead to serious issues.

So I’m going to remove the exiting breathers and extend the lines from the gearboxes to my new breather mounting block high in the engine bay.  Well that’s the plan.  However it does mean this fat old inflexible body will again have to squeeze and contort under the vehicle.  something I’m not looking forward to doing.


Dave Gibb said...

Oooooh!! 11 days That was quite quick for them then...... :-)
Contrasts a bit with when I was working (many years ago...) Irish Water Board sent a water Velocity meter to me for servicing and calibration.. Dispatched from Dublin Midday Friday, arrived at my workshop Monday afternoon, serviced on Tuesday, Calibrated Wednesday and calculations and paperwork sorted Thursady, dispatched from Christchurch Friday morning and delivered in Dublin Monday afternoon. Definitely NOT handled at any time by Snailways!! And that was Christchurch New Zealand not Christchurch UK.

Dave Gibb said...

Hi Tom. Looking at that kit I am curious as to why they do it that way?? Why have a separate breather/filter for each unit? They would not be moving very much air surely so why not just take one tube from the rear diff to the breather/filter and use a T fitting at the Transfer case/gearbox/ front differential to join into that. The fittings look like standard John Guest couplings so you should be able to pick up some T's easily and that would save having to find space to route four tubes through the engine spaces and would make it easier to fix one filter as high as you can get it. Just my 10 cents worth..

Tom and Jan said...

Dave you are quite correct in your observation. They could all be combined and I might do this at a later date as i'm thinking of installing an electric winch which will need breathers for the motor and gearbox. However I wasn't going to refuse the kit at the price they were asking.