1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Bosch S4 155 battery - how to fit vent tube?

Discussion in 'Gen 2 Prius Technical Discussion' started by OxfordPrius, Sep 4, 2014.

  1. OxfordPrius

    OxfordPrius Junior Member

    Joined:
    Aug 11, 2014
    6
    0
    0
    Vehicle:
    2007 Prius
    Model:
    N/A
    UK Prius user here - yesterday I installed a Bosch S4 155 size battery (£46 from EuroCarParts) in my '06 Prius, replacing what looks like an OEM/original battery.

    The fit is perfect (size and terminals) - except for the vent tube. The Bosch battery has two vents, one at either end, with a plug to bung one of them up. However, the vent holes are too small. I'd estimate around 5-6mm rather than the needed ~8mm of the vent tube.

    I reckon it might be able to be filed down to fit, but I was just wondering what others have done with this/other 3rd-party batteries where the vent tube doesn't fit?

    Thanks
     
  2. Feri

    Feri Active Member

    Joined:
    Jun 25, 2011
    761
    144
    0
    Location:
    Maldon Victoria Australia
    Vehicle:
    2010 Prius
    Model:
    III
    On the whole people don't buy batteries that don't have the correct vent hole. having said that I just purchased an Exide X60DPMF which is a calcium not AGM battery which doesn't have the correct size vent hole. However it is a fully sealed battery and doesn't need to vent. you should check whether yours is a fully sealed battery. If so you won't need to vent it. Usually batteries have two vent holes so you might need to block one hole while fitting the tube to the other if it is not a fully sealed battery.
     
  3. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
    2,002
    745
    0
    Location:
    Finland
    Vehicle:
    2004 Prius
    Car electronic shop just did give me battery vent tube fittings and hoses and one did fit perfectly. Before battery was just installed without vent tube.
     
  4. Feri

    Feri Active Member

    Joined:
    Jun 25, 2011
    761
    144
    0
    Location:
    Maldon Victoria Australia
    Vehicle:
    2010 Prius
    Model:
    III
    Are you saying the previous battery was installed incorrectly? That could be dangerous.
     
  5. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,855
    3,968
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    You have two options:
    1. Try and find a new elbow that will fit the new Bosch battery vent hole.
    2. File the existing elbow down a bit on the end so it fits your new battery.
    I did the latter when I fitted a Bosch S4 155.
     
  6. valde3

    valde3 Senior Member

    Joined:
    Jun 28, 2014
    2,002
    745
    0
    Location:
    Finland
    Vehicle:
    2004 Prius
    Yes and it was even installed by Toyota dealer. Its Toyota brand battery but not for prius and its not AGM.
     
  7. Feri

    Feri Active Member

    Joined:
    Jun 25, 2011
    761
    144
    0
    Location:
    Maldon Victoria Australia
    Vehicle:
    2010 Prius
    Model:
    III
    I wouldn't use that dealer again!:(
     
  8. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,917
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    Often screen wash fittings work as vent tube adapters. Even the screen wash tubing can be used. The gas flow rate through the tube in the vast majority of cases is zero. It is only when the battery is charged at an excessively high rate "such as when the battery fails with a shorted cell" that it is likely to gas at all, and even then the flow rate is very small.
    If the battery gasses continuously it will dry out and become useless in a few days.

    John (Britprius)
     
  9. OxfordPrius

    OxfordPrius Junior Member

    Joined:
    Aug 11, 2014
    6
    0
    0
    Vehicle:
    2007 Prius
    Model:
    N/A
    Thanks for the answers - in the end I just shaved off the original adapter with a craft knife and shoved it in. I figured if I still have the car in 4/5 years when then battery needs replacing again then I'll get another Bosch so it'll fit anyway!
     
  10. uart

    uart Senior Member

    Joined:
    Sep 7, 2009
    4,215
    1,202
    0
    Location:
    Australia
    Vehicle:
    2005 Prius
    Hi Oxford. I was in a very similar situation to this about 15 months ago when I replaced my OEM battery with a cheaper alternative. Mine also had two vent holes (each end) and they were too small to plug in that elbow joint. I ended up moving the elbow joint down to the other end of the tube (where it goes though the floor pan) and just shoving the rubber tube straight into the side of the battery. It was a tight enough fit to stay in place without any problems.

    Here are some pictures of how it went: Finally replaced my 8.5 year old 12V battery! Non AGM??? | PriusChat