1. Dismiss Notice
  2. Dismiss Notice
  3. Hey Facebook people... We've created a group for XS650.com members to connect. Check it out!
    Dismiss Notice

Air leaks up the wazoo

Discussion in 'The Garage' started by Noidea, May 22, 2019.

  1. Noidea

    Noidea XS650 Addict

    Hey guys back again haven’t posted here on a while been trying to just read more and answer my own question instead of repeating all the questions that are already asked, but now I’m at my wits end so here I am.
    I have a 73tx650 stock everything except my carbs are 76s, podfilters and step up jets.
    I have an air-leak at the right carb throttle shaft seals. The bores aren’t warped cause there’s no wiggle with the shaft.

    Previously both carbs had this leak I put orings and red grease along with newly purchased throttle shaft seals on both sets and the left ones were cured.

    I also notice when I spray brake clean at the headgasket below the spark plug on the right side I get some backfire and higher revving for that side. My compression is solid 145-150 both sides and when I did a leakdown test everything was sealing fine. I also did a retorque and no change when brake clean was sprayed.

    The only thing I feel I can do is purchase another rightside carb body and see if that works. But for the engine issue I’m
    Not sure what can be done for that. Any advice suggestions or inquiries would help and is always appreciated you guys help out so much it’s amazing thank you
     
    gggGary likes this.
  2. gggGary

    gggGary Stop that! Top Contributor XS650.com Supporter

    Have you got a second set of eyes that can take a look? Something just doesn't sound right about the leak near the RH plug.
    Post a video of your leak testing?
     
  3. solo2racr

    solo2racr Suck, Squeeze, Bang, Blow

    I thought air leaked OUT the wazoo!o_O
     
    Tim Meaders, Noidea and gggGary like this.
  4. Noidea

    Noidea XS650 Addict

    When I was working in a mechanic shop my coworkers helped me with leakdown and showed it was sealing I no longer have access to an air compressor I’ll actually buy one from harbor freight tomo to show you. [Also I meant the Rpms and backfire still happen as a result of spraying brake clean on the right side even after the retorque*.]Just a correction.
     
    peanut and gggGary like this.
  5. Noidea

    Noidea XS650 Addict

    It depends entirely on who’s wazoo we’re talking about here.
     
    peanut and gggGary like this.
  6. grizld1

    grizld1 Grumpy old man Top Contributor

    Do you see any oil or discoloration in that area under the RH plug? If not, you don't have a head gasket leak there. Could the spray be getting into the carb mount joint?
     
  7. Noidea

    Noidea XS650 Addict

    I don't have any oil leaking past it that's kind o of why I was confused and my compression is solid. I also forgot to mention I just bought new intake manifolds from niche cycles to eliminate that variable.
     
    peanut likes this.
  8. Noidea

    Noidea XS650 Addict

    I won't be able to get the compressor today to show you the leakdown test Gary. But If anything I can film a video of were I spray crab Clean and what happens during that process so y'all can see what I'm talking about.
     
    peanut and gggGary like this.
  9. gggGary

    gggGary Stop that! Top Contributor XS650.com Supporter

    yes the carb clean is my main interest.
     
  10. grizld1

    grizld1 Grumpy old man Top Contributor

    New mounts won't necessarily eliminate an intake leak. If Mr. Cavewrench went neolithic on the screws at some point, the holes can become extruded and prevent the mount from sealing. If you find raised edges, use a flat file (and some flat files aren't, check first!) with light strokes, followed by 320 paper, to level the surface.
     
    peanut, GLJ and gggGary like this.
  11. Noidea

    Noidea XS650 Addict

    I'll look into that manifold situation makes sense cause it seems like it's definantly still leaking I've been away for Memorial Day but finallly got around to making a video for you guys the link is here ->>

    As u can see my bike is still a rats nest needs wiring completely done etc I just want my engine and carbs to be tiptop before I start making other problems.
     
    gggGary likes this.
  12. Brassneck

    Brassneck XS650 Guru

    From the video, I think your leak is on the mating of the intake manifold to the head, or could be that the intake boots aren't sealing well on the carb...or even the vacuum port/cap could be suspect.

    If there was a leak at the head gasket, you'd have signs of oil coming out along that seam...it would be noticeable. My guess is it appears that there's a leak there but it's probably more likely that the fumes are being drawn into the intake as you spray it near the carbs first and then toward the front. If you sprayed from the front of the motor only along that head gasket seam (but only spray a little amount and stay between the spark plug and the exhaust header only), does the engine still rev higher?

    Also, could be the video but it sounds like your only running on one cylinder. Are both exhaust pipes hot/equally getting hot?
     
  13. Noidea

    Noidea XS650 Addict

    Yea the audio isn't the best on my phone for this sort of thing it's definantly running on 2 cylinders both exhaust are hot. I'll look into the manifold cause it defiantly seems Like there's an issue with it although it's brand new:/. I haven't really tried to spray the front of the engine on the right side between those 2 points I'll try it out If I spray At that what would that entail?I figured not having an oil leak would be a sign that my gasket is good just needed some more opinion.
     
  14. Noidea

    Noidea XS650 Addict

    With the sucking noise is that a positive way to notice that there's a leak within the carbs? That noise shouldn't happen correct?
     
  15. Brassneck

    Brassneck XS650 Guru

    My thought was that if you sprayed the seam (like you did in the video) but only towards the front of the engine (staying away from the intake side of the engine) so that the fumes wouldn't be sucked into the intake/carb area...if it still revs high, then perhaps there is a leak somewhere along the gasket...I've just not seen anything like that before, and it would help rule that out. Your spark plug is tight, correct? If it were loose, I suppose potentially it could suck in the fumes as well. And yes, I have forgotten to tighten a spark plug once and ran the bike...fortunately it was just around the block and didn't cause any damage. LOL

    The sucking noise is normal...you're hearing it more because of the pod filters you're using.
     
    TwoManyXS1Bs and gggGary like this.
  16. gggGary

    gggGary Stop that! Top Contributor XS650.com Supporter

    Grizzled makes a good recomendation but plug the intakes with rag or paper towel before filing, I'd stay away from sand paper the grit is the worst thing inside an engine. Then suck the rag out with a shop vac,
     
    grizld1 likes this.
  17. grizld1

    grizld1 Grumpy old man Top Contributor

    Right you are re. rags, Gary--didn't think it needed saying, but ya never know. Hard to stuff a rag so far into the intake port that you'd have to suck it out with a vac, though. Never had a problem with sanding debris; I don't go at it hard, just sand lightly with the paper wrapped tight on a flat file. What little bit of abrasive might come loose is caught by the rag--soak it with oil and it'll grab that stuff like a magnet.
     
    Last edited: May 30, 2019
  18. Noidea

    Noidea XS650 Addict

    Sound good ill do that as well as another check with the brake clean and get back to you guys with results.
     
  19. gggGary

    gggGary Stop that! Top Contributor XS650.com Supporter

    I've been fence sitting about saying anything and griz mentions it. But a warning; this is NOT a grab a file and start rasping operation. You are going in on the wings of an angel here. A VERY light touch with a fine file, the ONLY metal removal should be a small ring around the bolt holes. what you DON"T want to do is ruin the flat milled surface, or round off the edges, REQUIRED for a good seal.
    There I said it. I mention this and am sure Griz thought before posting because it would be SO easy to do more harm than good. Sorry if I offend because this is in your wheelhouse and you get it. On a similar project I saw the results of a guy who was too "enthusiastic" in his filing. Game over for the part involved.
    On the vac, it's not that the rags are so deep, but that the vac will be sucking out the metal shavings along with the rags. A needle nose to remove the rag, with the vac right there may be the hot tip. Again hope I don't offend. The level of mechanical savvy varies WIDELY on forums. Like physicians our first duty is to do no harm. A bit of tooth in the aluminum left from a fine file on the flange will do no harm, it helps to hold the sealer. As always; a great place to use Hylomar.
     
  20. grizld1

    grizld1 Grumpy old man Top Contributor

    Right you are, Gary--better too much information than not enough!
     
    gggGary likes this.

Share This Page