Simon Lumsdon 1

I have an SC 61A and had lots of trouble getting a reliable idle (spend time getting the low speed needle right) and it still doesnt like a quick throttle up, i suspect the large intake bore is the reason, lots of power but poor throttle up? Last time out i was contemplating adding some expo to the servo, once at 1/4 throttle its almost full power, very on off. I will have to give this a go since otherwise its a fine engine and once adjusted has been worth the effort

Completely agree with John, similar to cycling mag reviews, you need to read carefully for one questioning comment hidden in the detail which essentially says the product isnt any good

Interesting, reassembled engine last night, now all nice and smooth. Noticed the crank has a hole and feed into the back of the helical gear, i assume to lubricate it past the shielded bearing (which they make a big thing of in that ad, mentioned in first column also). Agree with your point on stainless bearings, will try that next time. Need to ensure i run engine dry at end of the day and use after run oil each time.

Its worn through the hardening, agree i need to look out for aa s/h damaged engine, will try polishing it, cant do any harm Regards the shielded rear main bearing, its odd since it would reduce lubrication to the bearings and cam assembly?

Think the engine was used nearly new, doubt it had been touched, double sealed rear bearing seems to be the original specification. I have ordered two skf bearings for < £8 and the rear will be open. Good point someone raised about the cam bearings, they seem fine but will try and get them out. one question, is it ok to try and polish out the pick up marks on the cam lobes and the rust on the followers with metal polish? suspect this is all my fault for neglecting to run engine dry and oil engine after each outing, must try harder in future

Front bearing front shield only Rear bearing double shielded, very crusty n rusty! Intended to replace rear with an exposed bearing

Was at the flying field yesterday flying my os52 cub and noticed bearings starting to feel a bit shonky. Stripped it down and engine showing signs of neglect, front bearing is rusty and slightly rough, just caught it in time. Rear cam lobe showing signs of wear and pickup, front ok, followers discoloured/rusty. Difficult to remove gudgeon pin, afain bit worn. Piston and liner seem perfect and think engine has more life left in it, we shall see… Anyway, question is, rear bearing is shielded with plastic cover, should i replace the same or use an open/exposed bearing? (Was surprised os use a shielded bearing here?) thanks

I have a cub with an inverted os52fs and it runs beautifully with standard setup (ie mounted normally on mounted centrally over the bulkhead hole (which is usually the centre point for an engine location) dont over think it 🙂

Have had similar experiences with poor throttle up on this engine, keep fettling the low speed idle and it should improve

You can sometimes find rudimentary throttled carbs that fit a Mills on ebay, i think a retired gentleman turned them up on his lathe for pocket money, pretty basic throttle but worked. I have test run it bit not put in a model yet

I had similar problems with this engine and would recommend checking the carb and needle valve o rings first, also try a different plug (they wear out) this carb is very sensitive to the low speed needle valve only small changes are needed and a lot of patience good luck

Cap head bolts and nyloc nuts all easily obtained from ebay, cap head bolts very easy to tighten and access using allen keys.

Hi John plenty of small diesels on ebay at very reasonable prices, if you save your searches they will pop up new items for you as they are listed, very handy, the downside is you will quickly have a shelf full of engines 😞

Completely agree 4 strokes are straightforward and suitable for a beginner, in my experience easy to start and idle/throttle easier than 2 stoke. I have found that there are plenty NOS (unused) SC and ASP varients on ebay which are a bargain and very good, on a par with OS but much cheaper. Enjoy

Thanks Grumpy, Airbrakes function looks like it will do the job, good spot!

Hello have read the manual umpteen times but cannot understand how to program a flap mix into a dual servo aileron wing? Have aileron servos on channel 1&6 using the 2AIL setup but want to drop both ailerons on a switch to mimic flaps? All help welcomed thanks simon

Oh and definitely post them separately

I think ebay is the best place to achieve a fair price, research their value by searching for similar on ebay beforehand, photo them carefully and give a clear description and start auction price at a realistic reserve price and you will sell them all. The wankels go for £500 and up, the remainder will be more modest prices but im guessing you will clear £1000, just be patient and put the effort in, good luck

My tip, place in bowl of boiling water for 5 mins, then use prop to gently free it, this usually works 🙂

Have noticed the same thing, also tried blowing down fuel pipe trick and carb is blocked when throttle closed, which suggests idle might be blocked, need to investigate that further

Engines are both in good condition with smooth bearings, o-rings are fine (and i do have spares), think these engines are just very sensitive to idle needle settings. Fuel is also fresh. Think i will stick to OS engines in future

Thanks John, sounds like a similar experience to myself, poor throttling being the main one, point about exhaust pressure makes sense and is going to be very helpful priming a cowled engine. Im also going to buy a Just engines geared starter, current one is too gutless

Well i didnt know the trick with blocking exhaust to draw fuel in so will try that. Will also check plugs are good. Agree with comments about these engines being sensitive to idle valve settings. Thanks

Sorry WOT wide open throttle

So have a couple of SC engines which are very bad starters and looking for advice please. Have googled all the threads on setting up high speed needle, low speed needle and trick blowing air into carb etc but no success. I have checked o-rings but they seem ok. First one is an SC61 in an Extra, inverted,12x6 prop, is a sod to get started but once running goes well, it throttles down ok although low speed idling is poor. High speed is fine, leans out nicely and throttles ok but low speed running a struggle. Getting it to start is hard since its enclosed in a cowl, inverted and doesnt draw fuel well when cranking WOT. Have tried the blowing into fuel feed when throttle open (ok) and when closed (blocked), adjusting idle valve doesnt unblock air flow, should it? Second engine is SC52 and its equally difficult to start, low speed idling is poor as is throttle up. Puzzling thing is neither engine seems any good at drawing fuel when WOT? Using a 12v gel battery and control panel flow feed which work fine on various 4 strokes and an fp40 (but they are all OS) Starter isnt the strongest, do i need a geared starter? Just to be clear, i can get the engines to run eventually and they sort of behave, its initial starting which is the main challenge? All ideas appreciated Many thanks Simon