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  • Fill through valve stem caps.

    Posted by Roscoeapproved on May 19, 2019 at 7:42 pm

    I picked up a 50 pack of the fill through caps several years ago via a link provided by Jon. I put 8 on the bus and i really like them. I decided to put them on all of our vehicles. I cant remember why now but i tried to remove one on our trailblazer and it was frozen on. I gently tried to persuade it off with a pair of pliers and broke the valve stem. Out of curiosity i tried the rest of them that i had installed and they are all frozen. Did i do something wrong? Is it because the passenger vehicles have brass stems and the fill throughs are stainless? Has anyone ever run into this?

    Second question. Jon, in another post you described the pass through valves as providing a second seal to the schrader. I guess that means that the schrader is not opened until you put a chuck on the fill through. Is that correct? Thanks


    Jeff and Lindsay

    91 Marathon XL
    Archived replied 7 years, 4 months ago 4 Members · 5 Replies
  • 5 Replies
  • Archived

    Member
    May 19, 2019 at 9:56 pm

    Perhaps you should have coated the brass valve stem threads with silicone oil prior to tightening your caps. My guess is they have seized because of two different metals.

    Do a a google search for “dissimilar metal corrosion

    Don Day

  • Jim/Chris

    Member
    May 20, 2019 at 7:22 am

    The Schrader does not open when fill through valves are used until the center portion of the cap is depressed, such as when filling a tire.

  • Archived

    Member
    May 21, 2019 at 8:51 pm

    Ok. Thanks Jon.

    Thats probably it Don. Seems its a common problem with steel caps from searching the net. I havnt checked if the bus ones are frozen. I think they are stainless stems though. Thanks.

  • Rick

    Member
    May 22, 2019 at 7:39 am

    I have the fill through caps on all the vehicles I own except the ones with Pressure Pro sensors.

    I have not had any problems removing or replacing the caps. I do not drive in the snow belt so I am not likely to get corrosion issues.

  • Archived

    Member
    May 22, 2019 at 5:18 pm

    I’ve not had any issues either with the short stainless extensions I use on my 365’s for the Pressure Pro’s. They were on my 02 for better than 4 years with no corrosion.

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