Derka Posted October 31, 2015 Share Posted October 31, 2015 (edited) I recently picked up a used Savage X with the Nitro Star 4.1 engine. It was sold as needing a new under head button which came today. I have been excited all week about getting it up and running.I got the thing started after priming and it seemed ok. I had re-set all the needles to stock (Flush) and the idle gap was about 1mm. I let it idle for 5 mins and drove some circles to warm it up as it was about 9-10c here before I set about tuning. I've watched dozens of videos and had made notes of what to do in certain circumstances to the needles, whether to lean it or richen it etc.Initially it was ok but I would stall on or just after full throttle on overun. I attempted to lean out the high speed needle which didn't really sort it out and there was not a lot of smoke so after trying to lean I richened it up a little but it would still stall.Then I couldnt get it to start at all. Engine was not flooded (I removed the glow plug and checked)Im a little dissapointed as I thought or had hoped it would be fairly simple to tune as I have a good understand of how an engine works.Assuming i'm not the problem (lol) Its running 20% fuel, some fuel the seller gave me and some Model Technics 20%.I guess I could try a new glow plug? It came with 3, 1 didnt work and 2 glow but may not be hot enough or something or worn.I like the engine side of things but coming from Brushless... man the noise its far too loud for me.Im thinking I need to try to get it running to sell it (or I could sell as a roller with everything but explain the engine may be duff etc)or convert to electric (I appreciate this is a Nitro forum)Im gutted, I had high hopes but didnt realise they were that loud! Edited October 31, 2015 by Derka Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) That's y I went brushless. ...I suck also at nitro if I'm honest. . ..could never get the knack of tuning them . .so I'm slowly selling all ours. . there sweet when they run ok.....but a r pitfa when they don't! !! Edited October 31, 2015 by evssv Quote Link to comment Share on other sites More sharing options...
Derka Posted October 31, 2015 Author Share Posted October 31, 2015 I noticed that whenever it stalled there was always a air gap on the fuel line to the carb but just assumed once the engine stopped the fuel slowly got sucked back into the fuel tank due the exhaust not pressurizing the tank etc.Anyway, not to be defeated Im taking a look again.I noticed when I blow into the tube on the exhaust to push fuel to the carb, fuel leaks out of the bottom of the high speed needle where it mounts to the carb housing.I took it off and the rubber o-ring is perished.Ive got some loctite high temp gasket maker and ive put a small amount around the surface as I dont want it blocking the fuel intake into the carb.So hopefully this will help some what as it appears an air leak can cause trouble on nitro engines and indeed any engine!Im going to let this gasket stuff set, so tomorrow I will start again but im not sold on Nitro lol.I do like the engine aspect of it as I love mechanics etc but the noise... I didn't realise they were that noisy! Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) Yeah i love the engine side of it but got fed up of it jus being a pita....admitly my hyper always ran sweet pretty much.. as do/did me boys savvy 3.5 . ..but. ...there's always the thought of it not working once u get out for a bash. .... Edited October 31, 2015 by evssv 1 Quote Link to comment Share on other sites More sharing options...
Derka Posted October 31, 2015 Author Share Posted October 31, 2015 Indeed, when you just want to stick a battery in bash the snot out of it but you can't because there is a lot more too it.Even if I got it running well, there is the noise aspect I had not realised was that loud so regardless I'm going to sell it or attempt to convert to brushless (but that maybe a new thread!) Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) Yeah I always said i'd never go brushless as there's no life to it like a ic motor. ..but after getting my first bl rc...my mt4g3. ..I knew there was no going bak. ....yeah it takes a while to wrap ur get around all the tec info ect. ..but it will sinkin...eventually. ....I been using brushless now oir around 2 years and ive had more fun bashing them then I ever did with nitro if I'm honest. ....sum people can do nitro ...sum can't. .I was in the middle. .. .. Edited October 31, 2015 by evssv Quote Link to comment Share on other sites More sharing options...
Derka Posted October 31, 2015 Author Share Posted October 31, 2015 Video one when it was running with default needles... https://www.youtube.com/watch?v=OM_jUprD-js No starting - https://www.youtube.com/watch?v=do24AJenfc8 Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) sounds a bit poppy in the first vid.... I could never get the tune right tbh. .. i watched vids. . .but still no joy..Ho well Edited October 31, 2015 by evssv Quote Link to comment Share on other sites More sharing options...
Derka Posted October 31, 2015 Author Share Posted October 31, 2015 (edited) I think i'll just stick it up for sale as is on eBay and maybe here.Hopefully get my money backSwap for your Savage Flux?!!!!!!! Edited October 31, 2015 by Derka Added some !!!! Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) lol......Nope !!!Hopefully sold me boys savvy 3.5 to one of his mates for xmas. .. ..so only me mtas50 to go then we b totally brushless then. ........although I do have a brand new force 5.2cc I wanna stick in sumin .....at sum point.......possibly Maybe.... Edited October 31, 2015 by evssv Quote Link to comment Share on other sites More sharing options...
RCbutcher Posted October 31, 2015 Share Posted October 31, 2015 Same here I watched hundreds of tuning videos but when it came to me tuning it was hit or miss ide usually end up getting it to run ok. The best tuning experience I had was a sumacher rascal at first it was a dog. I made it worse then slowly but surely got it perfect to the point I could see and hear the power differences from the hsn.I struggled more with the lsn so usually just got that as close to flush as possible. Most of my engines was traxxas engines and really well used too which didn't help. But a new glow plug was always the best thing I did. I really hope tuning 2stroke is easier. I really like the look of the new losi nitro engine it has tuning aid dial thing around the needles they might help alot for when you forget where you are which was my biggest pain. I always said i would never give up nitro and hate brushless, but things change lol. I said the same about stick radio vs wheel nnow swear by wheel radio. Quote Link to comment Share on other sites More sharing options...
Derka Posted October 31, 2015 Author Share Posted October 31, 2015 New day tomorrow, ill try again - glad im not the only one who couldnt get the hang of it.Been thinking some more and think I will just sell it on as spares/repair or as a roller Quote Link to comment Share on other sites More sharing options...
evssv Posted October 31, 2015 Share Posted October 31, 2015 (edited) Go fir it. . i did look at..and was tempted by the losi petrol truggy. .. . $299!!...absolute bargain. ... but no uk shipping. ..gutted!!If so I'd of had one for sure. . Edited October 31, 2015 by evssv Quote Link to comment Share on other sites More sharing options...
J.K Posted November 1, 2015 Share Posted November 1, 2015 Right then. You say you're using fuel that the seller gave you? How old is it? Nitro can "go off" over time much like unleaded so it MAY be worth getting yourself some new fuel.....ModelTechnics fuel is CRAP.It's always worth sticking a new glow plug in a second hand engine - OS8 plugs are well regarded for general bashing unless you have an engine with a "turbo" head which would require a turbo plug.Don't attempt to tune a cold engine. Factory settings are generally on the rich side for the break-in process, lean the HSN a further 1/8th of a turn and then run it until it's up to normal operating temps - only then can you start to tune for performance.Always tune in the following order: HSN, LSN, idle.You may have identified an air leak at the bottom of the HSN - it's best to replace the perished o-ring with a new one. Finally, welcome to the world of second-hand nitro - you have no idea how the previous owner treated the engine - did they follow the correct break-in process? Did they use after run oil after each run? Was the air filter correctly serviced?? etc, etc.Don't give up too soon - nitro CAN be a PITA but when they're sweetly tuned they're much more rewarding than plug and play brushless 1 Quote Link to comment Share on other sites More sharing options...
Derka Posted November 1, 2015 Author Share Posted November 1, 2015 Not sure how old the fuel was the seller gave. Hmmm Model Technics is the only fuel both my local hobby shops sell so that's a bummer. The Model Technics fuel is new. No idea about the engine to be honest. Seller said it's only been used 4 or 5 times in 5 yearsI'll try again today assuming the HSN is sealed up. If not I'll have to buy new washers/o-rings.I'm going to sell it anyway as Nitro is not for me. Hate the noise lol. Quote Link to comment Share on other sites More sharing options...
Anthoop Posted November 1, 2015 Share Posted November 1, 2015 I would not call ModelTechnics fuel crap....other than that I agree with the rest of what James said.ModelTechnics make many different blends/mixes of fuel, some of it is appropriate for RcCar use but most is not.....and some of the stuff that is appropriate for car use I would neither use or recommend.Which MT fuel are you using?...It will have a name where it says the nitro content...http://www.modeltechnics.com/glowfuel.htm Quote Link to comment Share on other sites More sharing options...
Derka Posted November 1, 2015 Author Share Posted November 1, 2015 20% Big Bang fuel with added sical. No fuel leaking now I heated engine to 70c with hair drier. Started ok but as soon as I touched the throttle it stalled. Kept trying and managed to do 2 mins of figures eights at barely any throttle and was ok. Then at idle was still accelerating. Adjusted idle down and now won't start again and rotor start is dead lol Max temp was 80c. I'm done!Cleaning it up and going on eBay! Quote Link to comment Share on other sites More sharing options...
spannermonkey Posted November 1, 2015 Share Posted November 1, 2015 Still sounds like an air leak. If you have decided nitro is not for you fair enough. Shame though because they are great when they run well and the constant tinkering is what most of us enjoy. Like I say each to their own and fair play to you for trying. 1 Quote Link to comment Share on other sites More sharing options...
gouldypg Posted November 1, 2015 Share Posted November 1, 2015 Richen the low speed half a turn see if it starts up and idles a bit better Quote Link to comment Share on other sites More sharing options...
chrisjw Posted November 1, 2015 Share Posted November 1, 2015 If anything, I'd say it's running too lean.............It's everyone to their own with regards nitro v brushless, but I personally, could never be tempted away from nitro.......I love the noise, the smell & above all, the challenge of getting it running right....I'm lucky though, as I've had the same car for 20 years now with the original engine still on it (although I have a spare one too), so I know every nut & bolt on the car & also enjoy stripping it down & rebuilding it...........keep at it.........it's worth it. 1 Quote Link to comment Share on other sites More sharing options...
Derka Posted November 1, 2015 Author Share Posted November 1, 2015 It is frustrating as I was SO excited about 1/8th scale monster truck and a Savage X!I don't mind tinkering, in fact, I have loved it.I just don't think I can accept the noise they make and that is stropping me from trying to get it running...Maybe I will regret it but its going on eBay for someone else to tinker with - Sorry guys! What a let down eh!! Quote Link to comment Share on other sites More sharing options...
stevo2551 Posted November 1, 2015 Share Posted November 1, 2015 I have a savage x with a 5.9 engine and it's usually a pita but when it runs good, it really flies. I usually take the trophy buggy flux out as well when I go bashing so either way I'll be going back home with a smile... 1 Quote Link to comment Share on other sites More sharing options...
Derka Posted November 2, 2015 Author Share Posted November 2, 2015 After chatting to a few people it seems the engine has low compression hence all the issues. Quote Link to comment Share on other sites More sharing options...
J.K Posted November 2, 2015 Share Posted November 2, 2015 After chatting to a few people it seems the engine has low compression hence all the issues.The easiest way to check the compression is to remove the engine from the car and hold it upright by the flywheel - the engine will naturally fall to 90 degrees but should then hold itself on it's own compression. If it falls further than 90 towards 180 degrees then you have a compression issue Quote Link to comment Share on other sites More sharing options...
evssv Posted November 2, 2015 Share Posted November 2, 2015 jus sell it and buy my xs...... .. Quote Link to comment Share on other sites More sharing options...
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