Engine Doctor

I sold a Moki 50cc four-stroke petrol a couple of years ago . That had a vey quiet exhaust note compared to any two stroke . The original mufflers usually fell apart so Alan from Weston UK made me a new muffler that made the engine whisper quiet . Only noticeable noise on the test stand was from prop and the rattle of the tappets .

Try speaking to your local council , they should be able to help or advise.

Hi edge flyer. Sounds like a relatively simple fix. Whats the problem with the pushrods its unlikely that they wear or have you lost them ? Any screws should be comercially available and its simple to make a gasket. Exhaust clips might be an issue but I thought the 75 exhuast was held in be grub screws ? Dont dump it you can do it and good luck.

Our LMS sells Tygon proper or the cheaper stuff without the writing on it as a lot of people wont pay the Tygon price . He does explain that the cheaper stuff WILL go stiff and not flex . Even proper Tygon goes stiff eventually but does take two or three years. The fake tygon is useless inside tanks for clunks as goes soft and slips of the pipes .

Try programming in a model and then leave for a day . It the memory hold ok then the back up battery is still working. If memory is lost ten it needs changing.

Sorry left out the price . £65 plus postage . UK only please.

Sorry PatMac I cant give any examples as I have never personally owned or flown this size or type of model , and to be honest the noise doesnt bother me unless its at my club and threatens our site. I have seen and heard many models at shows in the past that were very quiet when approaching on a fast low pass but as soon as they were level the prop noise was really loud like a shock wave being sent out that tailed off as the model flew away . This noise was most noticeable when at right angles to the prop disc . The turbo props were the noisiest wit very little motor noise but extreme prop noise . On full size aerobatic models that we often hear flying over our house have a similar prop noise ; hardly noticeable when approaching and most noticeable when directly over head and tailing off as they fly away . The large radial fours-trokes at shows in contrast made very little engine or prop noise .

As per title . Both engines have decent compression and fits and start easily . Fitted with Rc carbs from the era . £25 each plus post

One for the collectors .A replica K&B infant 020 glow engine new in box imported from USA many years ago . Possibly made by CS For an American company? Comes in original box that it was shipped in with letter from the seller and instruction leaflet , also a receipt of purchase for £95 back in 2006. Has lived in the box and as far as I know and has never been used . It has been carefully freed up as it was a little gummy. It also comes with a prop and two spare glow-plugs . It will be sent via insured post at cost . 20p in pic for size comparison .

As in title a bundle of 10 cox engines for sale . All turn over with compression and all glow plugs conduct power . They are gummy and will need cleaning and may have other faults but most if not all seem ok . one TeeDee has a damaged carb fixing . Also included is a DC bantam for spares . It has damaged thread on cylinder where some body has used pliers !!! Sold as a lot £110 posted only UK or collect from North Kent ME9 area

Full Marks to John H . he is the only one who took into account that Large props swing with a big enough Diameter for tips to go fast enough as fitted to big Petrol engines. PatMc Who mentioned anything about electric power ? The topic was about IC noise and silencers. The turbo props flown at shows a few years ago were a prime example of prop noise and horrendously noisy just from the prop tips going so fast. Possibly not supersonic but very near .

At our club we differentiate between " quiet electric" and "other electric flight" the other inc EDF and irritating things with little props is classed as ic and can only be flown at later times in the day as per ic models. Quiet as in "Very Quiet"; can be flown dawn to dusk.

This seems a bit cockeyed to me. Splines on output arm should be a snug fit on servo shaft or they are just the wrong size or spline count and a screw to lock the arm on should always be used. Using loctite or similar is just bodging the fault . Very nice to have blue annodised output arms but if the splines are wrong change them for arms that fit the servo properly with an appropriate screw.

Not sure if Colin is still active as I believe he was seriously ill some time ago. Has anyone ordered from him lately ?

Nothing new Leccyflyer. Eversince so called silencers were sold with engines they merely point the gunk and noise away from model. The so called mufflers supplied with modern petrol engines took this to a whole new level and IMO made the noise worse . Many flyers just dont get it and unless they are miles from anywhere will fly their models and risk loosing their site ; this and the fact that the general public are now less forgiving and will moan to their council at the slightest thing makes things worse. John H mentions the prop noise and this , while sounding great to us when doing a fly by is often the prop tips breaking the sound barrier and that noise can travel for miles .