Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

NP205 Leaks at the Speedo Fitting.....No Seals???

Discussion in 'The Garage' started by Greg72, Jan 21, 2003.

  1. Greg72

    Greg72 "Might As Well..." Staff Member Super Moderator

    Joined:
    Mar 5, 2001
    Posts:
    15,684
    Likes Received:
    1,392
    Location:
    642 Days to BB2018
    OK, I finally got tired of seeing the constant dripping of fluid off the fitting for my speedo cable on the NP205. It makes a big mess underneath, and now that I've got the High Angle Driveline e-Brake....having fluid all over the adjacent caliper and pads is NOT an option!!! /forums/images/graemlins/shocked.gif

    On my transfer case there is a fitting in a "recessed" pocket on the cast iron case that holds the nut and what appears to be the speedo drive gear (just a slender shaft with a gear at one end....has a "J" marking on it)...the output feeds into a Stewart-Warner offset block that must be another gear "adapter" to correct for speedometer errors....it goes into the NP205 fitting on one end, and then has a standard speedometer cable fitting on the other.

    Here's the riddle:

    I've taken the whole thing apart, and can't find any evidence of a seal that's missing, or a place where a seal could be installed to keep fluid from escaping (no machined "seat" areas...etc)

    I've shown the parts to a couple of guys I trust, and they are bewildered that THIS is the way the factory designed it.

    Does anyone have the "answer" for how the oil is contained, and IF there is a seal available somewhere? So far the only advice I've gotten is to "pack it tight with Marine Grease" and hope for the best........ /forums/images/graemlins/crazy.gif
     
  2. ZonkRat

    ZonkRat 1/2 ton status

    Joined:
    Jan 16, 2003
    Posts:
    1,003
    Likes Received:
    0
    Location:
    Lawrence County Tennessee
    Most I've seen have rubber oring around part that inserts into case.Should have groove around where it fits.
     
  3. Chris Demartini

    Chris Demartini 1/2 ton status

    Joined:
    Feb 17, 2000
    Posts:
    2,406
    Likes Received:
    1
    Location:
    Dumont NJ 07628
    <font color="blue">I thought only mine did this! It drips all over my VSS. Post up when you find a way to stop the leak
     
  4. Greg72

    Greg72 "Might As Well..." Staff Member Super Moderator

    Joined:
    Mar 5, 2001
    Posts:
    15,684
    Likes Received:
    1,392
    Location:
    642 Days to BB2018
    What's weird is that there really doesn't look like there was ever a provision on the gear driven shaft to seal it at all!!!

    I can probably show it to a machinist and have them "create" a way to install a seal, but I really want to hear if there is a factory part or solution to this!!!

    (Plus I don't want to spend out the a$$ for the machine work!) /forums/images/graemlins/grin.gif
     
  5. ZonkRat

    ZonkRat 1/2 ton status

    Joined:
    Jan 16, 2003
    Posts:
    1,003
    Likes Received:
    0
    Location:
    Lawrence County Tennessee
    Poss use a flat seal similar to distributer seal? /forums/images/graemlins/crazy.gif /forums/images/graemlins/truck.gifer /forums/images/graemlins/thumb.gif
     
  6. TheBlazerKid

    TheBlazerKid 1/2 ton status

    Joined:
    Apr 26, 2000
    Posts:
    259
    Likes Received:
    0
    Location:
    Raymond, Washington
    Mine leaks in teh same location. slow but steady.
     
  7. Sandman

    Sandman 3/4 ton status Author

    Joined:
    Apr 15, 2002
    Posts:
    5,653
    Likes Received:
    0
    Location:
    Pocatello, ID
    So does mine. I've considered goobering it up with silicon.
     
  8. 77fixer

    77fixer 1/2 ton status

    Joined:
    Nov 22, 2001
    Posts:
    464
    Likes Received:
    0
    Location:
    Meridian, ID 83646
    Is it leaking around the threads in the case, where the speedo adapter threads on, or where the speedo cable connects? When I rebuilt my 205, I used teflon tape around the threads on the speedo gear and drain/fill plugs. Not that it did much for me since my rear main is undercoating my rig.

    Brett /forums/images/graemlins/burb.gif /forums/images/graemlins/k5.gif
     
  9. therobzilla

    therobzilla 1/2 ton status

    Joined:
    May 15, 2001
    Posts:
    1,307
    Likes Received:
    0
    Location:
    Gilbert, AZ
    Greg,

    Here is the answer. The shaft of the speedo gear has a small o-ring that seals the shaft of the speedo. The speedo shaft and the screw in piece are seperat. The only way to fix the problem is to replace the screw in piece. It's only available from the dealer. Have them look up the piece on the computer. It's should be a stock item at a large GM dealer, it's somewhere between 20 to 30 bucks.

    The speedo gears on our 205 only use this o-ring. And it's build into the screw in piece. Aslo check the shaft of the speedo gear input for wear. Once I did this, all leaks stopped. Hell I don't even run a speedo cable, just a VSS for the TPI. Hope this helps.

    Rob
     
  10. Greg72

    Greg72 "Might As Well..." Staff Member Super Moderator

    Joined:
    Mar 5, 2001
    Posts:
    15,684
    Likes Received:
    1,392
    Location:
    642 Days to BB2018
    Thanks Rob....I feel like I'm starting to get somewhere!

    Here's a photo of the actual parts I'm dealing with....can you be more specific about "where" the seal goes?


    [​IMG]
     
  11. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ
    Digging up this ancient thread...

    Greg- what was the result, what did you wind up doing? There is a single lip seal in my 205 speedo adapter, NOT an O-ring.

    I'm half tempted to pound it out and match one from McMaster...
     
  12. Greg72

    Greg72 "Might As Well..." Staff Member Super Moderator

    Joined:
    Mar 5, 2001
    Posts:
    15,684
    Likes Received:
    1,392
    Location:
    642 Days to BB2018
  13. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ
    Thanks Greg! I bring da suckage at te sirch:pimp:

    Anyhow- Discontinued, no longer available. You might find a NOS somewhere, good luck, I don't seem to have any:doah:

    So I'm on a mission to find a seal...

    Metal case, single lip, no spring.

    .620 bore size
    .403 shaft
    .185 thick (can be slightly thinner or thicker)
     
  14. dyeager535

    dyeager535 1 ton status Premium Member

    Joined:
    Dec 13, 2000
    Posts:
    26,982
    Likes Received:
    191
    Location:
    Roy WA
  15. FWP

    FWP CRS

    Joined:
    Oct 11, 2000
    Posts:
    3,845
    Likes Received:
    3
    Location:
    Prescott Valley, AZ

Share This Page