990 Adventure Fuel Pump o-rings

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by rjm60, Jun 9, 2016.

  1. rjm60

    rjm60 n00b

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    2007 KTM 990 Adventure Fuel Pump O-ring Sizes
    Smaller o-ring (radial seal): 60 mm x 3 mm buna-n
    Larger o-ring (face seal): 65 mm x 3 mm buna-n

    I just about finished painting and re-assembling my 990 (long story) but I sliced the radial seal o-ring on the fuel pump while trying to re-install it.

    I read a bunch of stuff and found out that rather than pay $50 for 2 KTM OEM o-rings, people have found McMaster-Carr substitutes.

    Unfortunately, I had already ordered and paid for the OEM's before finding the McMaster-Carr substitutions. I supposed I could have measured the grooves and guessed at the right size but I didn't (just wanted to get back on the trails ASAP).

    Fortunately, I decided to measure them before installing.

    While many have used a size 932 o-ring to replace the radial static seal (most people re-use the face seal o-ring), the actual size is 60 mm ID x 3 mm cross section diameter. This is only slightly different than the 932 but I believe it's the correct size.

    I've also seen size 229 (I think) used but this has a 3.5 mm cross section diameter and, although slightly smaller than the 60 mm, it has much more volume (total material) to squeeze into the o-ring groove, which is about 2.5 mm deep and 3.5 mm wide. That said, it has been used successfully. Note that the hole in the tank is about 65 mm in diameter.

    The face seal o-ring is 65 mm ID x 3 mm cross section. I've read that size 230 has been used here successfully. Although it has much more volume than the 65 mm one, I guess it works because it's a simple face seal and the groove is about 4 mm wide, providing plenty of space for the o-ring.

    Also, Viton is not necessary. The buna-n material works just fine with gasoline and ethanol. That said, since the buna-n o-rings come 100 to a package for $14.95 and you can get 5 Viton o-rings for half that, most people go with the Viton.

    Lastly, I've read and experienced the difficulty in getting that fuel pump back in the hole without shearing off the radial seal o-ring but someone said they did it by using the 4 screws to pull the pump in evenly. This works great. I also put a little oil (vacuum pump oil - mineral oil) on the seal and the hole before installation just ion case (just a film). This is a very good technique.
    #1
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  2. Chuckracer

    Chuckracer Jerkus Maximus

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    Mods, can this please be stuck or added to the Hall Of Wisdom...or something?
    #2
  3. guglemonster

    guglemonster Crivens!!! Supporter

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    guys, this has been solved some 5 years AGO :)

    there is a kit in the vendor list, mine, there are plenty of info, also mine and from others inmates, about size, better size, international size, codes and whatnot :)

    the best combination for all LC8/RC8 fuel pumps are

    65x3.52 VITON

    59.99x2.62 VITON

    use motor oil :)

    NBR is a very cheap solution, point is it really swells a lot, far too much, while Viton, in MY measures, can be reused no-end.

    I understand that NBR o-ring you can put in a bag under the seat, but I prefere not to have to take THE WHOLE bike all the time :)

    :D:D:D:D:D:D:D
    #3
  4. rjm60

    rjm60 n00b

    Joined:
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    It may have been solved 5 years ago but apparently it wasn't documented well enough to find with a search.

    Maybe you could post some links to all this info from 5 years ago.

    I posted/reposted all the related info I found on several forums and websites. It's nice to have it in one spot.

    This is all the info I could find on these o-rings. I could not find any kit besides the OEM one for $50. I only needed the o-rings. Didn't need any filters.

    The sizes I gave (60x3 and 65x3) were measured from the OEM o-rings I bought from KTM. Your sizes may work but they are not the correct sizes.

    Viton is great but you don't need it. Also, McMaster-Carr doesn't have the 65 mm o-ring in Viton. That said, I would buy the smaller one in Viton (as I stated above). The smaller one is the one that usually gets messed up when trying to re-install the pump. You could re-use the larger one. It's a face seal and won't get messed up when re-installing.

    NBR might swell but who cares (Viton swells too, just 100 times less). If you're going to replace the o-ring, you'll probably buy the Viton one anyway but if you get the NBR o-rings, you'll have 100 of them, so you'll replace it every time. Besides, the swelling will just make it seal better.

    Thanks
    #4
  5. guglemonster

    guglemonster Crivens!!! Supporter

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    Mate, no offence, I never intended to offend anyone :)

    the KIT is JUST for the o-rings, and did it in order to help out since it was so hard to find parts and correct sizes, I posted many many times not only size but also international codes :)

    btw, original ones ARE WRONG, it was shown many times, we checked it with machinery experts and many many times and for many years implemented, on my bike they are on since 2011, not one drop, and believe me, I do take down the pump pretty often to try new protos, new filters and check fuel cap filter efficiency on the pump filters, like I always say, swap the radial one and let it dry, it will gain back it's size in a matter of days, maximum weeks, ready for next installation, always use MOTOR OIL :)

    at the base, should the tank be irregular o warp, happened in many cases both with Safari and original tanks both on 990 as well as 1190, the thin 3mm will not help, the thicker one yes

    as for the radial, its' only purpose is to avoid vibration and resonance that would add stress to the bolts in the plastic, its' size is WRONG it was done so thick to make it impossible to mount it back once used................ I'm sure there are plenty or inmates that are good and can mount it back, I have plenty of mechs friends and customer that thought they mount it perfectly to find out that it was not the case, usually in the middle of nowhere with petrol leaking from the plate..............

    here again all sizes and international code

    as for VITON, forget Automotive parts, go for industrial heavy machinery, better quality, all sizes, top service :)

    5-703 168 65,09x3,53 BASE

    2-142 3237 59,99x2,62 RADIAL

    2-10 2025 6,07x1,78 ROD

    2-11 2031 7,65x1,78 FILTER AND QUICK FUEL DISCONNECT

    2-129 3156 39,35x2,62 WHITE PAPER FILTER CASE

    2-123 3118 29,82x2,62 PUMP RUBBER ANTI-VIB

    this is the one-year old post

    http://advrider.com/index.php?threa...elow-fuel-cap-for-ktm-bmw-and-others.1054490/.

    but you're right, a simple o-ring search didn't show up anything else, it is in the fuel pump-ectomy done in 2007
    again, I meant no disrespect,

    :D:D:D:D:D

    oh, btw,

    same size and codes apply to all LC8/RC8 1190 ad 1290 bikes, :)

    here's the post to which I was referring to

    http://advrider.com/index.php?threads/in-sight-to-the-990-fuel-pump.461827/

    :D:D:D:D:D:D

    this is an AMAZING FORUM, if we don't have it, we will invent it

    !!!!!!!!!!!!!!!!11

    :D:D:D:D:D:D:D
    #5
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  6. MattF44

    MattF44 Been here awhile Supporter

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    I am really dense it seems. As much as the above is spoon feeding me the information, I'm still confused somehow.

    Can someone help me understand which o-ring to purchase if you have a slightly warped fuel filter opening? My mechanic just replaced my filters and went through three o-ring kits and some perimetex trying to get a seal. Unfortunately, it's leaking again after a very hot ride home.

    Thank you.
    #6
  7. guglemonster

    guglemonster Crivens!!! Supporter

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    Hi @MattF44

    The radial one, 60x3, has the main function to keep the pump from tilting, the main one 65x3 is the sealing one.
    Now, warped in what direction? Did you check planarity of the coupling surface? You may wish to go entirely another way, first with liquid steel compound get planarity in check and than, maybe with the help of slightly longer bolts, use a thicker oring like the one I'm suggesting/selling in my kit, 65,09x3,53 USA code 5-703 EU code 168

    You may even try a thicker one still 66,04x5,33 USA code 2-333, but I doubt you cam fit it in the groove

    Keep us posted

    Cheers
    #7
  8. MattF44

    MattF44 Been here awhile Supporter

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    Guglemonster:

    I can't thank you enough for your guidance. A long time KTM mechanic has been working on the bike and was having a hell of a time getting the pump to seal. The tank seems to have become warped at some point -- likely when he had them off to do the valves and a couple other things. Regardless he thought it was all set, but it opened up again and I'm getting a drop or two every ten seconds.

    I'm going to share this information with him in hopes it'll help.

    I still have to order the pre filters from you and will be sure to get an o-ring kit too -- I just need to get the thing running reliably prior to the fine tuning as these repairs have my budget out the window.

    Again, thanks very much and look forward to talking in the near future.
    #8
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  9. guglemonster

    guglemonster Crivens!!! Supporter

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    Hi @MattF44

    If it's really a drop issue, the 65,09x3,53 USA code 5-703 EU code 168 will almost for sure help you out

    The original one has too little "lip" sticking out of the base plate, but make sure the mech will not over tighten the bolts, the in-built nuts may come off suddenly, we saw it happen here in Italy once, guy tried to re-use the same oring for the 4th time but it didn't seal, so used too much strength and boooom baby, we couldn't recover the tank, luckily there are a few out there for fair price all year long ;)

    Are we talking about the original tanks or Safari ones? My bad for not asking it at once.

    This is a great community, either you help out if you can, or you're just ballast for the bilges ;)

    Keep us posted

    Cheers

    Bill
    #9
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