EvilC57

Going back to this earlier post. May I just defend myself: By saying that I run engines on the rich side, I'm following the manufacturers instructions; in that as per the instructions for both 2 and 4-strokes, I run them slightly to the rich side of peak RPM when on the ground. I.E. In accordance with the following diagram, which appears in the instruction manuals for a number of OS engines. And also: The instructions for the RCV58-CD which say, "Main needle (high speed) adjustment: The main needle should be adjusted with the engine operating at full throttle. The engine should be leaned out until the RPM peaks, then enritched a small amount. This will allow for the leaning out that normally occurs in flight.". The instructions for an OS MAX-25FSR I also own, which say, (after running in) "After six to ten flights, it should be possible to run the engine continuously on its optimum needle setting. This setting is with the needle valve adjustment 1/4 to 1/2 turn on the rich side of the position at which the engine reaches its very highest speed. Your engine can be said to have completed its running-in period when it holds a steady speed at this optimum setting. Never attempt to gain a few more RPM by running the engine on a lean setting; it will run hotter and may eventually become damaged by over-heating.". I'm just doing what the books say 🙂.

Yes I did. I picked off the remains very delicately with a scalpel, and used a small soft wire brush afterwards. I didn't want to attack it with wet & dry and risk reducing the diameter. It looks (under a x7 magnifying glass) and feels completely smooth now. The brass washer from the crankpin was more of a problem. That had some stubborn deposits of aluminium from the old conrod on one side of it. This I cleaned off using very fine wet & dry (used wet) in a circular motion on the end of my finger against a smooth surface. Being careful to remove all the aluminium, but none of the brass. I can only do what I can do to ensure it's perfect during reassembly. If it fails again it'll go in the bin, and I'll turn my attention back to eBay for a replacement engine.

No I'm not sure. The cylinder bearing is running smoothly now, and my understanding of other people's efforts at replacing it leave me a little reluctant to try it unless I have to.

Right, time for an update and some questions. I decided after all that as it seemed only a new conrod was required, I’d go for a careful cleaning of the the engine, followed by an equally careful rebuild. I managed to remove the rotating cylinder with the aid of a heat gun, a small wooden drift and a rubber mallet. The large ball race then being exposed. This felt slightly gritty, and on washing it out I noticed a fair amount of what looked like aluminium swarf in the bottom of the plastic container I used as a bath. The bearing still felt slightly gritty but was perfect after being kindly blown out by a friend with a compressed air line. Fitting the new conrod with the lubrication cutouts at the front, as suggested by Martin Harris and others in the thread suggested by Manish just above, gives the conrod an offset toward the front of the piston (see pic below) - I know the crank pin circlip is not fitted yet. Can this be right if it’s not in the the middle below the piston? It could be argued that there should be another washer forward of the big end, however none was fitted originally, and no washers at all are shown on the manufacturer’s exploded drawing of the engine. Looking at the remains of the old conrod compared with the new, you could almost believe there was no oilway in the big end. Once the rest of the engine is sorted, I might try filing into the remains of the big end to see whether I can see any trace of the hole that should be there.

However, I've just remembered a thread I started here a while ago. Make sure the receiver has the latest software installed.

It would appear so. I took the pictures below while on holiday in Tibet a few years ago, where it is a sacred symbol in the Bön religion (a minority branch of Tibetan Buddhism), and predates its use by Germany by hundreds of years.

Yep, I have several of them in use with my DX8 Gen 1.

Yes, I’ll strip everything down as far as I can and give it all a thorough wash out; presumably in fresh fuel being the best thing. Unless anyone knows better, I can’t get the rotating cylinder valve out, as looking at the exploded diagram here it seems to be retained by a large circlip, which once installed in the upper crankcase casting, can’t be accessed to remove it.

Who knows? That was my thought too. As I said in an earlier post, it is inverted in the model. But the instructions specifically say it can be run inverted (like every other glow motor I’ve come across). I’m careful to run engines on the rich side. I’d rather have the reliability over absolute peak RPM.

I’ve just got around to having a closer look at the engine, having stripped it down a bit further. Damage appears to be confined to the conrod big end. Having removed the circlip and remains of the big end bush from the crank pin, the pin itself seems OK - maybe just needing a bit of a clean up. The inside of the cylinder and the piston seem perfect, with no scoring that I can see or feel. I called Weston UK yesterday, and they quoted £10.50 (inc VAT) for a new conrod, and £19.99 for a crankshaft - but I don’t think I’m going to need that. So for just over a tenner, I think I might try and get it going again, after a good bath and a cleanup to make sure I’ve got rid of any conrod debris. It’s still worrying though, as to how the big end came to seize in the first place.

Good point re routing the crankase vent back to the carb Manish, it would explain the threaded hole. As I've said in previous posts, I'm becoming less inclined to try and repair it, as it has an unknown history regarding fuel etc. I'd rather spend the money on what looks to be a better one on eBay or similar.

OK thanks for your suggestions Jon. The crankshaft bearings seem free enough at the moment, but as you say, they really need cleaning out to make sure. I don't have an ultrasonic bath, maybe I should treat myself to one sometime. As you say, it was only a tenner so I'm not sure it's worth all the effort of trying to get it going again. By the time I've bought all the bits that may be required (with no guarantee that they'll actually fix it), I'm inclined to wait and see what comes up on eBay in terms of what looks likely to be a good runner.

Some interesting points there thanks Martin, Jon & all. I’d observed that the crank pin looked dry, but (stupidly) dismissed it. Is it possible for the pin to be dry? If so, I guess it might also explain why the crank case bearings appear to have been spun. Yes the piston moves OK In the cylinder, so presumably we’re looking at lack of lower end lubrication - the engine is inverted when installed in the model, but they’re designed to run at any angle aren’t they. Well done for spotting the mod to the carb inlet, it appears to have been drilled and tapped for some reason. Buy hey, I only paid £10 for the engine as I say, at a bring & buy. But as they say, buy cheap, buy twice. So, if I get in touch with Weston to try and get a new con rod and crank shaft, bearing in mind the apparent lack of lower end lubrication, what’s to say it won’t seize again?

Another one broken! I was flying my large twin yesterday which has a pair of RCV58s in it, when after 5 minutes or so in the air the model seemed to lose power. I managed to land just short of our patch, with no damage fortunately. On inspection, one of the engines had lost its alloy spinner cap, and the prop was loose (which is what fooled me into thinking both engines were still running, as the loose prop on the dead engine was windmilling). All evidence of a sudden stop in flight. On removing the engine today, and splitting the crankcase, the big end has broken off and the crankpin appears damaged. The engine which failed was bought cheap at a bring & buy sale a few years ago (unlike its twin which was bought new), and reading Engine Doctor's post above (August 25th 2015), it seems the piston may also have got grabbed by the rotating cylinder and twisted off. The other engine has always been run on sythetic, but unfortunately I don't know the fuel history of this one, although I remember having to clean a number of brown castor stains off when I first got it. Seems the previous owner may have known something I didn't 😕! The decision has to be, do I try and repair it, or scrap it and turn to eBay?

Nope.

It’s not just us. How many times have we seen TV news (particularly on the BBC) postponed because they’re covering a sporting event such as tennis or football. We’re not all sport mad, but it seems the rest of us have to make way for those who are.

That one looks real. However I've always suspected that the ‘Prototype Quadrotor with Machine Gun!’ one is some kind of set up or fake.

Reminds me of an old video on YouTube, search ‘Prototype Quadrotor with Machine Gun!’. I won’t embed it here as there is some mild profanity.

Beautiful model. But when I went up to the LMA show at Cosford recently, we took the free bus over to the museum, where one of the the museum guides spent 10 minutes slagging the original aircraft off while standing beside a real one. He listed so many shortcomings that I can’t remember them all, but included being under powered and too slow to intercept the bombers it was sent to shoot down, over complicated undercarriage, and a turret which he reckoned would fall out if the aircraft was inverted.

We bought a 2016 Mini Cooper for my wife a couple of years ago. When I came to do a routine check on the oil level, I found it had no dipstick. Looking into this, the only way to check the oil, is to go into an ‘oil level check’ function in the car’s multimedia system menu, and with the engine running, wait for 1 minute while the computer takes control of the throttle and does a check with an inbuilt sensor. Dipsticks worked OK for the first 100 years of motoring, and I can’t see what’s wrong with them myself!

I have absolutely no idea! I don’t even remember having it in the first place. The picture by the way, was I believe, taken on a touring holiday in Southern Ireland. I remember my parents had made up a bed on the rear parcel shelf for my baby brother to sleep on as we drove around. You couldn’t IMAGINE doing that now, but I guess it was before child car seats were invented!

Yes I believe my father’s was one of the very earliest models, and as you say, a lot of the problems should have been picked up on the PDI. However I guess standards were lower 60 years ago.

I had a 1968 Austin 1100, and a 1972 Austin 1275GT myself (although why my father went along with them given his experience with the 1100, I don't know!). Both rusted for a pastime. And I remember pulling the handbrake up in the 1100 one day, and it came off in my hand. All 4 spot welds had broken away; soon drilled out and replaced with nut & bolts. I seem to remember that in the 1275GT, the exhaust manifold kept cracking and needing welding up to stop it blowing. And in cold weather the twin SU carburettor dash pots used to freeze up on long motroway runs, meaning I had to put my right foot down harder and harder to get any power out of it.

My late father kept diaries dating from when he was young in the 1940s, right through until shortly before he died in 2009. I inherited these, and have just got around to reading through a number of them (the ethicality of this is for another discussion!). In early January 1963 he bought a new Morris 1100 ( I just about remember this, as I was about 6 at the time). It seems that in the week he bought it he wrote a snag list, as follows: Driver's inner door handle sticks in open position. Blister in paint on boot lid. Chips in paint on delivery. Loud buzz behind dashboard. High petrol consumption (26mpg). Offside rear door difficult to shut. Headlamps need setting. Engine runs on after switching off ignition. Steering stiff and sqeaks (won't castor). Boot lid rubs body. Windscreen washers u/s. Engine lumpy and hunts on hills. Offside windscreen wiper misses window. Courtesy light u/s. 2 weeks later, there is a note which says "Finished underseal". Remember those days of doing your own?! In the middle of February he wrote a 2nd snag list, as follows: Near side rear door leaks. Driver's door handle still sticks up. Rubber boot on gear lever split. Loss of coolant. Front passenger seat adjustment jammed. Clutch judders in 2nd gear. Indicator won't cancel when turning right. In June he lists a number of things he needs to do himself to service the car, including: Clean and check points & plugs, check tappets, weaken mixture, set timing advance. In July he wrote a 3rd list: Boot on gear lever split again. Near side front window winder faulty. Clunk from wiper motor. Clunk from suspension on pulling away (rear drag link?). Offside front corner of car hangs low. There are various other references to car suspension hanging low throughout the year. Seems BMC's hydrolastic suspension wasn't up to much - like most of the rest of the car!. We don't know how lucky we are today!!! Me with the offending car in about 1963 or 64 (I no longer have the rubber duck).