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Savage X4.6 tuning problem

Discussion in 'Nitro Engines' started by Tommi_82, Jun 6, 2018.

  1. Tommi_82

    Tommi_82 Member

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    Hi!

    And first of all, sorry for my bad english.
    I'm kind a noobie with these, so maybe this is stubid question.

    I buyed my Savage about a year ago, last summer goes pretty well and all worked just line meant to be.

    But in this summer, just feels that i don't get all of power out of engine.
    I tried to tune hsp, and just when car starts to move like it meant to be, engine heat goes way too high, about 150-170C
    Engine sounds pretty normal, and gives outnice white smoke, nothing doest refers that engine is too lean.
    When i loose HSP to get heat about to 120C, it just don't give out any power.
    I'm using pretty much stock setup, only difference is robinson racing clutch bell and spur gear and HPI high performance clutch.
    My heat meter is HPI ultimate tuning screwdriver

    What I'm doing wrong?
     
  2. olds97_lss

    olds97_lss Well-Known Member

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    Could be your LSN is too lean or rich and your fighting with that. If your LSN is too rich, a lean HSN compensates for it. A lean LSN is also compensated for a bit by a rich HSN. Usually, changing one much requires adjusting the other.
     
  3. Tommi_82

    Tommi_82 Member

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    Visited in garage today and checked my LSN, looks like its in stock setting (hadnt have no need to tune that) is it still possible that screw is too rich or too lean?

    Also noticed that i don't have to screw HSP so much than last summer, in last summer optimum spot was somewhere in 1-1,5 turns, now even 0,5 turns is too much.
     
  4. olds97_lss

    olds97_lss Well-Known Member

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    Could just be gunked up on you from sitting. Might want to take the carb off, take out the needles and the LSN/HSN assemblies, clean them and check the o-rings. Orings in carbs don't last forever. They tend to dry up when sitting and then they leak badly causing bad tune or your tune to adjust on you as the engine runs because they don't keep the needles in place. It's best to put some associated green slime on them to help keep them conditioned and for sealing.
     
  5. Tommi_82

    Tommi_82 Member

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    Sounds logical...
    In weekend i have planty of time to check the carburetor. Also ordered green slime today, i believe i got it before weekend.

    Is there anything to know when dismantle carb?
    Just take off carburetor and then unscrew needles and they come out that way?
    Is there anything that i can broke with unknowing?

    What size are o-rings? I think its better to get new ones allready before to do anything...
     
  6. X

    X Conspiracy of One
    HPISF Staff

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  7. olds97_lss

    olds97_lss Well-Known Member

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    Nothing real special to know. Just don't overdo it when putting the needles back in so you don't damage the needle or seat. If your replacing o-rings, make sure to get the green slime to lube them before putting them on the needle to help avoid tearing them. Take the carb completely apart as in, remove needles, idle screw, the main slide part, the HSN assembly as well as the needles out of the HSN/LSN parts.

    Then when putting it back together, use RTV to seal both sides of the main fuel inlet, carb neck and carb cinch bolt. It can be a bit of a mess, but put it all together, then wipe off the excess RTV before it cures. Make sure to use "sensor safe" rtv. The permatex ultra copper is what most people use. I usually use a q-tip with the end cut off to apply the stuff.

    The last rtv I bought was Permatex Ultra Grey RTV Silicone Gasket Maker. Not sure what's different about it, but it's advertised for use with high vibration applications. I got it because it was grey and doesn't stand out like a sore thumb as I was getting it to seal a sensor plug on my castle brushless motor. Once cured, seems pretty much the same as the ultra copper as far as pliability.

    Here's a thread about sealing an engine if you want to brush up on it:
    https://www.hpisavageforum.com/threads/nitro-engine-sealing.15150/

    Considering the time it takes to do the carb, might be best to do the backplate as well. Will give you a chance to inspect your clutch bearings and shoes too since you will have the engine out.
     
  8. Tommi_82

    Tommi_82 Member

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    Doesnt hear very difficult, so i think that i try seal whole engine in weekend.
    Lets hope that helps with original problem.
     
  9. olds97_lss

    olds97_lss Well-Known Member

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    At the very least, it rules out air leak as an issue. Check your exhaust gasket as well. They can get pretty chewed up on a savage.
     
  10. Tommi_82

    Tommi_82 Member

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    Nothing new under the sun...
    I check the carburetor and sealed engine yesterday, today was test drive day.
    Engine still heats up just before when fun starts...
    I believe theres something wrong in my HSN, it feels kind of loose, no any resistance when try to tune it. O-ring was in good shape, but it ”profile” was like square, not round like all others, also in pictures of carb o-ring set all of rings are round, not square
    I tried to replace it with same size of standard o-ring with round profile but it was impossible to put needle back on its place so i don't know was original o-ring ok or not?

    Anyhow, local dealer has great discount of f4.6 carburetor(only 20€) so i think i order brand new carburetor and try with that.
    If aint work with that i dump whole thing in carages cabin and try to find new hobby...
     
  11. olds97_lss

    olds97_lss Well-Known Member

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    You can try soaking the o-ring in fuel to make it swell back up a bit.
     

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