WillyChang 1814 Posted January 16, 2020 I don't think baking it is going to do much good. I'd be soaking it in Liquid Wrench or acetone for a few weeks 16 hours ago, Andy Stewart1 said: That piston don't look too healthy. How's the supply market for a new piston & sleeve? Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 16, 2020 48 minutes ago, WillyChang said: I don't think baking it is going to do much good. I'd be soaking it in Liquid Wrench or acetone for a few weeks That piston don't look too healthy. How's the supply market for a new piston & sleeve? Er.. non-existent. Why, do you think this one has bitten the dust? Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 16, 2020 Yay, I’ve got the carb off in one piece. It’s all soaking in a petrol and TFR cocktail. Ive moved onto the radio gear and the silver contacts in the battery compartment of the handset covered in green oxidisation. Any tips for getting rid of this!? LoL I might just buy a new set but if I don’t have to I won’t. Hopefully I can start building it back up soon and I’ll just post a picture of the finished article and stop bothering you kind people. Thanks again for the support so far. Might stick this bodyshell on it. Can anyone guess what it is? Share this post Link to post Share on other sites
junkmunki 846 Posted January 16, 2020 29 minutes ago, Andy Stewart1 said: Yay, I’ve got the carb off in one piece. It’s all soaking in a petrol and TFR cocktail. Ive moved onto the radio gear and the silver contacts in the battery compartment of the handset covered in green oxidisation. Any tips for getting rid of this!? LoL I might just buy a new set but if I don’t have to I won’t. Hopefully I can start building it back up soon and I’ll just post a picture of the finished article and stop bothering you kind people. Thanks again for the support so far. Might stick this bodyshell on it. Can anyone guess what it is? That body looks very much like a Nissan Sylvia... Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 16, 2020 11 minutes ago, junkmunki said: That body looks very much like a Nissan Sylvia... Close! It is Japanese. Toyota corolla ae86 I’ll have to take the front drive shafts out to authenticate the rear wheel drive action! Just don’t want to have to cut out a ‘sunroof’ lol Share this post Link to post Share on other sites
WillyChang 1814 Posted January 16, 2020 Umm... have you sized it up? That hachi looks like HPI AE86, they'll be 190mm... that's "PureTen" size in Kyosho language aka 1/10 Touring Car (although nitro TCs are 200mm; electrics are 190mm). These old Kyosho nitro rally with OptimaMid-derived suspension are "SuperScale" aka "SuperTen" later on, they're 225mm wide afaik. Essentially they're as wide as a 1/10 Buggy (Optima) and length is Long Wheelbase OptimaMid. Share this post Link to post Share on other sites
WillyChang 1814 Posted January 16, 2020 9 hours ago, Andy Stewart1 said: Er.. non-existent. Why, do you think this one has bitten the dust? Fuzzy unfocused pic but piston looks pretty scored. btw DO NOT EVER clean/polish the piston or its sleeve at its curved cylindrical surfaces. Whatever carbon is built up there helps sealing for compression. Without compression your engine will never start again; if it won't run it can't regenerate carbon coating. Piston is matched to its sleeve, don't intermix with another pair. If ever I remove piston from engine for maintenance, I'll slide it back into its sleeve and leave it alone until reassembly. Nothing needs doing there, except preventive changing of the conrod occasionally. When compression is bad, wornout piston & sleeve needs renewing as a matched pair. Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 17, 2020 7 hours ago, WillyChang said: Fuzzy unfocused pic but piston looks pretty scored. btw DO NOT EVER clean/polish the piston or its sleeve at its curved cylindrical surfaces. Whatever carbon is built up there helps sealing for compression. Without compression your engine will never start again; if it won't run it can't regenerate carbon coating. Piston is matched to its sleeve, don't intermix with another pair. If ever I remove piston from engine for maintenance, I'll slide it back into its sleeve and leave it alone until reassembly. Nothing needs doing there, except preventive changing of the conrod occasionally. When compression is bad, wornout piston & sleeve needs renewing as a matched pair. Good advice thanks. I did notice the scoring on the piston, this isn’t a reflection. Should I take the sleeve/piston out of the de-gunking bath then? It’s just that the conrod was very stiff and presumed this would need a degunk. If this doesn’t run it’s not the end of the world, I’ve learnt how to rebuild a 1/10 IC engine, and I’ll look for another suitable one, but I would be so happy if it did. This weekend will check the glow plug battery pack holder and see if the glow plug still functions. Share this post Link to post Share on other sites
WillyChang 1814 Posted January 17, 2020 Yeah might be no use cleaning up that piston; at most clean out gunk from where the smallend pun goes but that's about all it needs. Scoring means grit has gone thru the filter &/or been run without filter. Little nitro engines are very finicky on air leaks, when reassembling I slather on heaps of RTV silicone at every joint that can leak - carb to body, backplate, exhaust to manifold. No need at head to liner, the shim & button does that. Throw away any old plug, don't even bother reusing. Buy some new plugs, I like OS #8 or A3... works great in every engine from OS10 to 21/25/28s. The only thing better than a new plug is a New Plug that's been tested good when you've got a well tuned engine running sweet, open some new plugs and run them in that engine for a tank. Then remove & store away. Brandnew plugs occasionally leak compression or the coil doesn't keep glowing without electric stimulation - engine dies soon as you remove glostarter. If you need to buy a glostarter, best ones have some form of current draw indicator. Either a meter or LED, helps eliminate chance of bad plug or flat battery when you know juice is flowing. Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 17, 2020 Ah thank you. That was a question for later - can I use gasket sealant in places where the gaskets were previously. Would this be an ok type of glow plug to buy? https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F232489440320 Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 17, 2020 The original car came with a glowplug starter that carried 4 x D cells... Are these ebay 1.2v starters going to work? e.g. - https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F324032436871 Share this post Link to post Share on other sites
WillyChang 1814 Posted January 17, 2020 6 minutes ago, Andy Stewart1 said: The original car came with a glowplug starter that carried 4 x D cells... Are these ebay 1.2v starters going to work? e.g. - https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F324032436871 maybe it's 4 Ds in parallel for drycells, plug only needs 1.5V but a fair bit of current. Yeah those pocket igniters can work, I've got a few of them plainjane ones like that but 1, don't like the fixed cell (you need to charge in situ, can't change cell when it dies) & 2, there's no indication of current flowing. (I keep spare plugs on my plug wrench. I might stick igniter on one of those plugs to test if battery is still working occasionally... but you won't know if plug in engine has gone bad.) This is the best design I've found... https://www.ebay.com.au/itm/122255528105 had current meter, takes a loose cell - can charge cell separately, can carry extra cells to swap in. Have seen them sold in subC, C & D sizes. Share this post Link to post Share on other sites
WillyChang 1814 Posted January 17, 2020 https://www.ebay.com.au/itm/122255528105 Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 18, 2020 I’ve taken the sleeve and piston out of the cleaning fluid. I tried to insert the piston in the sleeve and it wouldn’t fit. I got a bit of oil and eventually I have got it in and moving freely. But only to the point where the piston is fully into the sleeve, the port almost fully closed just a small gap showing. Is there a maximum point where it will not and should not go past? Share this post Link to post Share on other sites
WillyChang 1814 Posted January 18, 2020 18 minutes ago, Andy Stewart1 said: I’ve taken the sleeve and piston out of the cleaning fluid. I tried to insert the piston in the sleeve and it wouldn’t fit. I got a bit of oil and eventually I have got it in and moving freely. But only to the point where the piston is fully into the sleeve, the port almost fully closed just a small gap showing. Is there a maximum point where it will not and should not go past? insert the piston only from the bottom of sleeve The piston shouldn't travel up all the way to the top edge of sleeve, usually the head button protrudes a little bit into the sleeve. The glowplug screws into the button; there's usually a small hemisphere cavity where combustion happens. With a new/good piston & sleeve, as the piston nears the Top(DeadCentre) of its designed travel, it should start getting stiffer. The sleeve narrows to "pinch" the piston at the top of its travel. This aids sealing for compression. Ports are closed when the top of piston passes them. Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 18, 2020 Thank you. I’ll just have to keep giving it some persuasion. Dremelled off the contacts of the Glow plug starter and it’s giving 1.6v attached it to glow plug but nothing (actually I crock clipped the earth onto the screw thread?) like is it supposed to ‘glow’ or just get hot? Anyway new plug definitely will be ordered. Daft question time. Does this fuel actually ‘go off’ ? This tub is nearly full! :-) I’ve had petrol in the garage for years for cars and it’s been ok. Can you still buy this stuff or what’s the nearest equivalent ? Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 19, 2020 https://www.elitemodelsonline.co.uk/More/Fuel/Aero-Fuel/27609-/GX16-Expert-1-Lit Share this post Link to post Share on other sites
WillyChang 1814 Posted January 19, 2020 20 hours ago, Andy Stewart1 said: attached it to glow plug but nothing (actually I crock clipped the earth onto the screw thread?) like is it supposed to ‘glow’ or just get hot? Anyway new plug definitely will be ordered. yeah they glow red hot, the coil bit anyway. Once the engine is running & electricity is disconnected, the coil absorbs & stores the heat from combustion to help ignite the next ignition cycle. (This is where plugs can differ "hotter" or "colder") Plus some minute ants of rare metals that aid as catalyst to combustion. 1 Share this post Link to post Share on other sites
WillyChang 1814 Posted January 19, 2020 20 hours ago, Andy Stewart1 said: Daft question time. Does this fuel actually ‘go off’ ? This tub is nearly full! :-) I’ve had petrol in the garage for years for cars and it’s been ok. Can you still buy this stuff or what’s the nearest equivalent ? Toss it out. Model fuel is pure methanol + 5-35% nitromethane + 6-10% castor oil for lubrication (this don't burn). Methanol is hygroscopic, it'll absorb water from atmosphere and water don't burn. Once you've opened the bottle it's stale within weeks. There's real noticeable differences in how engine performs on fresh vs stale. Buy fuel locally from an LHS with good turnover; it'll go stale unopened sitting on shelf or cold concrete garage floor. I've got LHSes that homebrew their own fuel, they do their blending under a head of nitrogen gas to avoid moisture from air. Nitromethane is the dearest component, higher % costs more. But smaller engines really prefer higher %, it's much easier to start & tune - don't go below 20%. Ok ok ok I'm thrifty... if I have some stale fuel leftovers (like weeks old, not years) I'm loathe to tip it out. I'll open a fresh bottle and start the engine with it... then once it's warmed up I'll top up the tank with the less-fresh. Once that runs low, top up with same again... unless starts spluttering then it gets trashed. I always start a cold engine with HALF tank of fuel, it lessens risk of flooding. Top up after its running & warmed up a minute. Also I only tune engine when tank is Half and engine is fully warm. And best to pick a nitro% and stick with that, don't chop & change. Usually have to retune for every different fuel, you don't need that hassle. 1 Share this post Link to post Share on other sites
WillyChang 1814 Posted January 19, 2020 5 hours ago, Andy Stewart1 said: https://www.elitemodelsonline.co.uk/More/Fuel/Aero-Fuel/27609-/GX16-Expert-1-Lit Be wary... that's "plane" food same idea but I think planes don't need as much oil or nitro as their engines stay throttled at constant speed for long periods (don't need snappy throttle response) & there's ample airflow. try this: https://www.elitemodelsonline.co.uk/More/Fuel/Car-Fuel/7557-/BIG-BANG-20-455-LIT-1-GAL When we raced & needed to import fuel, yep Model Technics "molecular blended" was the most reliable brand available at the time. Used to arrive in paper cartons of 4 gallon jugs. Good memories. 1 Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 19, 2020 Sorry for the rubbish picture but Is this about TDC? Share this post Link to post Share on other sites
WillyChang 1814 Posted January 20, 2020 yeah that looks about right Pop the liner onto the button in the head/heatsink to confirm. 1 Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 21, 2020 My battery holder came yesterday so I put all the radio gear back together. Handset pushing 10 with new batteries :-) Well it all works but I remembered how pathetically slow these servos are/were. Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 21, 2020 Got the carb freed up nicely tonight. Started to assemble the chassis. Could spend hours making everything gleam but I am way too impatient. Share this post Link to post Share on other sites
Andy Stewart1 18 Posted January 25, 2020 Well the engine is mainly back together but the pull start will not turn the engine. I’m wondering if this chap is seized up the inner part of the bearing should spin, right? Share this post Link to post Share on other sites