Mick Cayton Posted August 25, 2015 Share Posted August 25, 2015 I have one of these engines and have just run it up. It's nicely made (as you would expect) and runs well. However; do not touch the low speed mixture before you start the engine. I thought it was a good idea (with my glow head on) to richen the idle adjust before I ran it in... then I tried to start it... then I read the instructions. It didn't start of course so I got the electric starter out and the only way I could get it to fire up was to spin it over with a screwdriver on the low mixture screw and screw it in until the engine fired - not easy on my own with the engine in a plane. The engine fired and would not rev - it kept cutting out as I opened the throttle. The main mixture screw was again too rich - I had opened it half a turn too much. I have now set the main mixture and the engine starts easily - by hand - and revs well. Do not treat this engine like a methanol glow engine - it won't start. I have two previous petrol engines: a DLE 20 and 30, but the experience didn't help. If you have an OS glow petrol engine, don't be a bloke - read the instructions first. It will save alot of effort. I have this engine set up in a Black Horse Orbit with flight controller, OSD and a screen on my transmitter. I havn't flown it yet (expect to next week-end) and I expect the engine to perform very well, but before you touch it you must RTFM! Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted August 25, 2015 Share Posted August 25, 2015 Looks good, saves on using a extra battery and ignition. Might be the end of the pure glow engine if the trend continues... Quote Link to comment Share on other sites More sharing options...
Phil Green Posted August 26, 2015 Share Posted August 26, 2015 ... and no ignition interference! Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 27, 2015 Share Posted August 27, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Mick Cayton Posted August 27, 2015 Author Share Posted August 27, 2015 I think OS are defintely onto something with this engine: It's nicely made; gets (almost) as much power as a 46-50 two stroke; it weighs the same; no messing with the extra weight of ignition, mounting or radio interference (as Phil observed) and it's VERY cheap to run. The other bonus is I always have fuel and don't run out on a Saturday evening - I always keep some petrol in the shed for the gardening machines and I keep a stock of good synthetic oil on the shelf. By the way, the blurb says 50:1 - I'm running-in on 25:1, but I doubt I'll ever push it to 50:1. Pulls nicely on a 12 x8. In answer to Percy's observations, I have wondered what the petrol glow plugs will work in... Might try one in a 91 four stroke or even an AX120... I suspect the petrol glow plug might have set some sort of ball rolling... Quote Link to comment Share on other sites More sharing options...
Former Member Posted August 27, 2015 Share Posted August 27, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Mick Cayton Posted August 27, 2015 Author Share Posted August 27, 2015 It could work if I stick to high oil content - around 20:1 and use the carb very gently. Petrol/air stoichiometry (wondered if I'd ever get that to use that word...) is about one third that of alcohol so the threads are that much more coarse on the mixture needles on conventional glow carbs. In the GGT10 instructions OS make a particular point about fuel contamination and even the tiniest fragments being capable of blocking the carb. They also say don't dismantle the carb(?). The engine has a tiny filter in the line between pump and carb; they also say don't run in on the ground because of the risk of the engine sucking in dust. I have only run it after rain and I use lots of new petrol filters. Petrol filters are important because the mesh glow type are too coarse and allow particles through of a size that will block the OS carb. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 27, 2015 Share Posted August 27, 2015 Is it a pumped carb Mick? I've got the Evolution 10cc and it's the one weak point, in that it relies on exhaust pressure which doesn't really provide as stable a supply as the engine would like which makes setting the mixture a bit hit and miss, even with the built in regulator. Even with a needle roller big end the Evo needs 20:1 mix. I see the OS has a rear crank cover pump and runs on 50:1! Edited By Bob Cotsford on 27/08/2015 11:37:20 Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted August 27, 2015 Share Posted August 27, 2015 Enya do a petrol 2 stroke that doesn't need an ignition, but has to use special oil which is over £40 for a small can. Never seen one run, but for £599 for the engine and extra for the silencer way too expensive. Edited By Paul Marsh on 27/08/2015 13:52:42 Quote Link to comment Share on other sites More sharing options...
stu knowles Posted August 27, 2015 Share Posted August 27, 2015 I'm just curious why, when you have already admitted to one 'bloke' activity, - changing the carb setting without reading the destructions, you then do the same again by ignoring the manufacturers recommendations on the petrol oil mix? just a thought Quote Link to comment Share on other sites More sharing options...
Mick Cayton Posted August 27, 2015 Author Share Posted August 27, 2015 Hello Bob; Yes it is pumped - the pump sits in the backplate and the carb looks quite sophisticated. I think it's regulated. It responds to tiny needle movements. The recommendation is to set the low speed mixture then open the throttle and go to the high speed setting. I think the tank could be positioned anywhere in the model. For Stu's benefit, the running in requirements are for a 25:1 ratio. For regular use OS recommend 25 - 30:1 (I suspect that's to cover mineral oil use) although they have checked Klotz ModeLube, Amsoil Saber, etc at 50:1. I would think you could go quite lean on a racing synthetic - which I use, but I never run my petrol engines leaner than 40:1. Quote Link to comment Share on other sites More sharing options...
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