Steve Thomas 3 Posted November 2, 2014 Share Posted November 2, 2014 Hi everyone, First of all I am New to the forum, I'm Steve Thomas, I live in Taunton, Somerset. I use to do a lot of model flying many years ago but gave it up. The Thing is I have been left a model Keil Kraft Supper 60 with an OS Max-H 35 Glow engine which has not run for many a year. The prop will turn over although it is tight, I have taken the glow plug off and turned the engine over by hand which is ok but as I say it is abit tight. What is the best way to go to be able to start it ? Thanks for any help anyone may be able to give me Steve Thomas (Taunton) Quote Link to comment Share on other sites More sharing options...
GONZO Posted November 2, 2014 Share Posted November 2, 2014 Is this engine ballraced like the OS Max-40 RC **LINK** in this test report? If so I would advise removing the engine from the airframe and removing the engine rear back plate. Check for any rust/corrosion. DO NOT RUN the engine before ensuring that there is NO rust. If you run the engine with rust inside it acts as a grinding paste and rapidly wears/wrecks the engine. Warmth and some fresh fuel will loosen things up, but do check for the rust first. Let us know how you get on. Quote Link to comment Share on other sites More sharing options...
Charles Smitheman Posted November 2, 2014 Share Posted November 2, 2014 Hello Steve, welcome. If I recall correctly this is a plain bearing engine, and the chances are that it was run using castor oil as lubricant. This dries out in time. Add some fuel to it, turn it over gently (do not force it) and it should loosen up quite quickly. Many of these older engines had a cast iron (Meehanite ) piston. I think that it is recommended to use more oil in the mixture than with modern engines, 25% castor oil. Please correct me if I am wrong. folks. Charles Quote Link to comment Share on other sites More sharing options...
GONZO Posted November 2, 2014 Share Posted November 2, 2014 I thought steve may have meant this engine OS MAX S-35 **LINK** at first but as he refered to it as an OS MAX-H 35 I changed my mind. I would agree on the oil if it is a cast iron piston, but 20% should be OK as its probably well 'run in'. If it is ball raced it may well have a piston ring and then any modern fuel with 5%-10% nitro would be OK. Quote Link to comment Share on other sites More sharing options...
GONZO Posted November 2, 2014 Share Posted November 2, 2014 OS Engines Manufacturing Timeline shows it as being introduced in 1966 **LINK** From the picture it looks to be ball raced, could be two or as OS did sometimes one ball race at the crank web end of the crankshaft with a bushing bearing at the prop driver end. This may also lend weight to the possibility of a piston ring. This would need to be free in the piston groove to ensure correct running. Personally, with all engines new to me including new ones, I strip down and check before use. Quote Link to comment Share on other sites More sharing options...
Steve Thomas 3 Posted November 2, 2014 Author Share Posted November 2, 2014 Hi Guys, Thank you very much for your help and advise I have looked at the link of the 1966 one and that is the same, I will try to get some fuel this week and a glow plug lighter, put some oil with the fuel and try to run it and see how it gose. I'll let you know. Thanks again for your help Steve Quote Link to comment Share on other sites More sharing options...
PatMc Posted November 2, 2014 Share Posted November 2, 2014 It could be the 35 RC version of this Max-H 40 which only has a single ball race. I have one but can't find it listed in the OS timeline link. It has a split silencer (old Merco style) and an exhaust baffle linked to the throttle, not sure but I think the silencer is fitted directly to the crankcase with screws instead of using a steel strap like some other OS engines of that era. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted November 2, 2014 Share Posted November 2, 2014 Welcome to the forum Steve..... The Super 60 & an OS35 should be a nice combination......as the others have said it's probably congealed & dried up castor oil that is making the engine a bit stiff. Plain bearings are very common in older engines & these last a lifetime usually. Personally I would strip it down & give it a good clean out inside....some meths will probably get rid of the old castor oil.....the carb will probably be gunged up too so don't forget to strip & clean that out too. If the model is very old then I'd check all the plastic components too as aged plastic often goes brittle.....hinges/horns/servo arms...possibly the engine mount too.....I'd be tempted to replace them all....likewise the prop if its an old nylon one....failure in these components would probably cause a crash which would be a shame... Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted November 2, 2014 Share Posted November 2, 2014 The Max-S were plain bearing engines, the Max-H were ball raced. Both are good engines, and bought a good 40 Max-H from a swopmeet last week for £5. Started on the first flick, after priming. If it turns over ok, and these engines were ran on caster, probably the bearing is gummed, but maybe ok for a while longer. Quote Link to comment Share on other sites More sharing options...
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