Rich Griff Posted December 15, 2020 Share Posted December 15, 2020 I have a now old Magnum gp40 which has had lots of gallons of fuel run thru it ( hi boy for 4 yearsish, then 5 or more years in a 4 channel wot 4 ish type model ) and more, but it still runs great. On its last removal and clean down, its third, i notice that the gudgeon pin ( wrist pin ) white plastic ( nylon ? ) "Buttons" that keep the gudgeon pin in place, are wearing a bit thin on the end float faces. Where can it get some new ones from, or are similar parts fitted in other makes of engine that will fit? I can measure them up over Xmas break.... All help greatly appreciated, stay safe out there 😊 Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted December 15, 2020 Share Posted December 15, 2020 They will be PTFE - available in bar form from firms like Chronos and probably on Ebay. If you have a friend with a lathe he could turn up a pair easily or you might even be able to DIY using a small file with it held in an electric drill. Don't let it get hot if you DIY - it gives off harmful fumes above 300 C. Quote Link to comment Share on other sites More sharing options...
Robin Colbourne Posted December 15, 2020 Share Posted December 15, 2020 Hi Rich, Welcome back! Just engines advertise a wrist pin and retainer for the LEO 37 engine for £1.57 (part 2002), Just Engines -J'EN 37 spares You could try calling them to see if this would work, or ask if they have anything more suitable. Alternatively there are three Magnum 40s under £25 on ebay. It would be worth posting a picture here, so the contributors who are knowledgeable can advise if you really have a problem. Some engines are designed to have a degree of end float on the gudgeon pin. Alternatively there are three Magnum 40s under £25 on ebay. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted December 16, 2020 Share Posted December 16, 2020 Hi Rich the old Magnum GP 40 is pretty much a clone of the OS FP and many parts like the piston liner assemblies were interchangeable so the pads from one of those should fit if you can find on old clapped example cheaply. Quite a few makes used these pads so a bit of research should find some . Are they really too thin as the bit that protects the liner is a bit like a mushroom top . As already said if unavailable commercially then a DIY set are not difficult to make. You could give Alan a Weston UK a call as he may have some spares from the later Magnums ( SC/ASP ) that used simila r pads left in stock. Edited By Engine Doctor on 16/12/2020 10:24:42 Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted December 16, 2020 Author Share Posted December 16, 2020 Thanks for the heads up, the PTFE round bar stockist has loads of stuff, need a small adjustable reamer for an old bike engine....will also contact Weston about the top hats... Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted December 16, 2020 Author Share Posted December 16, 2020 I contacted Weston and they e mailed back very quickly ( take note vosa who are not even accepting e mails at the moment, on Xmas holidays probably ) saying the Magnum gp40 is a thunder tiger, and not from the Weston range. Will try just engines next... Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted December 16, 2020 Share Posted December 16, 2020 I didn't think the early Magnum GP 40 was anything to do with Thunder Tiger ? Any way the top hat PTFE parts that the Modern Magnum engines (nothing to do with the early Magnum engines ) use would probably do the job . That's the trouble with e-mails I guess . Nothing like actually talking to someone. I have a couple of OS 40 Fp engines for breaking . If your stuck let me know and Ill check for the parts you need I think I may also have some internals from a Magnum 40 that had a broken crank case . Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted December 16, 2020 Author Share Posted December 16, 2020 Thanks engine doctor, perhaps some parts from the "scrap" Magnum gp40 may be for sale, like piston with rod and the cylinder sleeve, and possibly the carb, or even the complete dead engine? Anyways that's for after Xmas. Not yet learnt who to post pictures via the phone, no land line or internet at home except via the phone....Gunnar need the lads help with them me thinks😁 Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted December 19, 2020 Share Posted December 19, 2020 I'll Check them out and get back to you . E.D Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted December 20, 2020 Share Posted December 20, 2020 Hi Rich PM sent E.D. Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted January 2, 2021 Author Share Posted January 2, 2021 Hi E.D. pm sent Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted January 3, 2021 Author Share Posted January 3, 2021 Hi E.D. pm and e mail sent. Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted January 17, 2021 Author Share Posted January 17, 2021 Hi ED, the parts you very kindly sent me will do fine and extend my original gp40 working life. I now have some spares for this engine to keep it going, and when finally "run out" , a cylinder head etc. to play with for further petrol fuel experiments. The spare crank may find its way into a home brew engine... The gudgeon pin pads are still "domed" and will be fitted on next strip down and clean... Itching to get back RC flying... If there is a seller's rating system on here I give you 100per cent. Thanks again, much appreciated, stay safe out there...rich. Edited By Rich Griff on 17/01/2021 09:53:08 Quote Link to comment Share on other sites More sharing options...
Pvougi Posted January 11, 2023 Share Posted January 11, 2023 I just bought a brand new Magnum 40 GP R/C ABC 2 stroke engine. It didn’t come with a glow plug so I was wondering what the recommended part would be. Also..what is the recommended fuel to run? Is there a premixed version I can just buy/order that’s ready to run as is? being that it’s brand new, what’s the break in procedure and do I use same fuel for break in as I would when flying? Thank You in adavance Pete Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 11, 2023 Share Posted January 11, 2023 OS #8 Runs well on 5% nitro. Start it, tune it for peak rpm, back it off by 500 rpm or thereabouts. Run it on the the ground for a tankful, full throttle for 30sec, back off for 15sec, then back to full throttle. Then go fly. Same fuel as normal. GP40 is a carbon copy of the OS 40 FP - you could look up the manual for that engine easy enough, search the net via the usual sources. 1 Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted January 11, 2023 Share Posted January 11, 2023 DON'T run it in on the bench, run it rich in the air or the chrome will disappear ,,, "experience", as I sold a few in my shop. Quote Link to comment Share on other sites More sharing options...
Jon H Posted January 11, 2023 Share Posted January 11, 2023 Is it ABC? I cant remember. If so Nigel's procedure seems completely appropriate to me. There is no reason i can think that a ground run would damage the engine unless it was to ingest something nasty. 1 Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 11, 2023 Share Posted January 11, 2023 (edited) Just don't run it in slobbering rich. ABC simply needs to get straight up to normal temperatures. Running in an ABC engine is mainly about work hardening the conrod, if I remember rightly. The piston/liner fit should be pretty close right from the get go. As an aside, one of my OS 40FPs actually has Magnum GP internals - piston, liner, and crank. Edited January 11, 2023 by Nigel R Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted January 11, 2023 Share Posted January 11, 2023 Beware there are a lot of fake OS No8 glow plugs about, there's a thread on this forum somewhere that shows the difference. I guess someone can put their finger on it. Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted January 11, 2023 Author Share Posted January 11, 2023 Pvouge, did you get the instruction sheet with your engine ? I initially ran mine with an idle bar plug on straight castor for ages. Then discovered Enya no 3 plugs. As the engine got older I went up to 5 percent nitro, still runs well even if it is a little worn now. 1 Quote Link to comment Share on other sites More sharing options...
Jon H Posted January 12, 2023 Share Posted January 12, 2023 19 hours ago, Nigel R said: Just don't run it in slobbering rich. True for running in all engines! Quote Link to comment Share on other sites More sharing options...
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