Olaf Pedersen

Fuel was from 1982 ish, about 40 years old, opened it, can was rusty outside, perfect inside. Mk2 started but I couldn't stop it v.v. noisy with a graupner 10x6, omitted to clean the fuel cut off orifice. The bees tank was incontinent but eventually got it running. God the smell from that fuel was far worse than I can recall. Both engines the contrapistons are very tight, I shall have to tap them out and polish the liners. I shan't be reporting back as I see you have some pathetically woke moderators here, so I'll subscribe elsewhere, probably RCG. Bye all.

Lead/tin, I didn't dare use the modern, less toxic stuff for fear of either melting the transfer case solder or distorting the liner or both. I have a litre of diesel fuel unopened from the late 80s but I think I'll buy a new tin as ether seems to find its way out of everything.

PS I thought it looked a bit cockeyed, unsoldered it and re-soldered it, it's the way the fitting is machined.

I used a heatsink made out of rolled aluminum kitchen foil poked into the liner to dissipate unwanted heat. Engine now re-assembled and plopping nicely

Da - da, tested and leakfree.

Bingo!

Tim, many thanks.

Forgot to mention, looks horribly like the flange at the bottom is also soldered on.

The example I have has desoldered from the cylinder, I'll have to make an adaptor to fit both the cylinder and any carb I choose to fit. It's a bit awkward as the transfer port at the front is also soldered on and they used soft lead solder which will be at risk if I'm too heavy handed. But I've nothing to lose as it's US without the carb.

Thanks but I already have dated them, fwiw, plenty of gen on the internet. Don't buy magazines anymore, same old same old.

Got a couple of old diesels on the weekend, don't know why as they were rubbish back in the day and won't have improved over the years, one was an ED mk1, the original bee complete with tank, the other is a mk 2 competition special. Both were seized absolutely solid and the mk 2 had lost its carb, the adaptor having desoldered at some stage. As per usual the engines bore all the hallmarks of pre-teen engineers, mullered cheesehead screws and pliers hieroglyphics all over. Managed to get all the screws out of the mk2 and eventually got the front cover and seized crank adrift, ditto with the cylinder and piston . Gentle heating and the alloy cylinder head unscrewed then a brass drift and a hammer and tapped the contra-piston down til it contacted the piston then tapped them both out together, a few drops of auto transmission fluid after tapping the c-p back up the bore and then onto the crank, bit more heat and the crank came out, more atf, reassembled and it's now plopping like a good one. The mk 1 bee wasn't as seized and only needed a few seconds with the heat gun after removing the tank and carb tube and it freed up, some more atf and it, too, now plops beautifully. I'll have to try to find a carb and so on for the mk 2 but the mk 1 is ready to run. I had several of these engines back in the day, but was extremely fortunate in that my father had a set of cabinet makers screwdrivers and taught me how screwdrivers should be ground so that screws didn't get mullered, sold all the engines at the nats one year. I've had a Tomboy itch for a couple of decades and now I have the engine around which it was designed iirc, ie the mk1. I have heard that the mk2 has been known to power a j 60, I am refurbing mine so if I can cobble a carb together may try it in that.

Made the trip to cocklebarrow today, 330 mile round trip, it's the first time for a long time and it's the only time I've ever flown there when there's been next to no wind, thermals in abundance and my southerner major dead sticked as I ran out of fuel that's a first for me. Lovely landing if I say it myself but that's always the way with dead sticks. It was the first time the os 52 surpass had been run for many years, probably around 10 so I was pleased it lasted, but that's always the way with OS isn't it.

A good way of gauging if it's too windy is to place the model on the ground, with radio off and the elevators set to up. Point it into the wind and let go of it. If the wind blows it away, it's too windy for that model.

I changed my mind in the end and fitted the turnigy, saving the laser for a 1/4 scale cub I have to repair.

Does the 70 FZ have the sealing ring on the crankweb? If it does that might be worth examining as I think but can't remember for sure if that ring runs direct in aluminium which might explain the black stuff. IIRC high oil content is to insanely assist with cooling the engine as most of these engines used to end up in competition aerobatic ships where constant speed in manoeuvres is helpful toward scores hence v. high throttle settings in the vertical which may explain it away as these tend to be frequent and of relatively long duration. Much of the blowby oil is recycled through the engine in any event so gives it a double whammy as Maggie used to say. I have to say that I never was a competitive flyer, using the ys just using my YS like I used my lasers, OS etc. TBH I used westons liquid gold 20% nitro in all my 4 strokes, I was happy with it. BTW YS recommended modifying the piston by drilling 3 x 1/16" diameter holes equally from the crown to the root of the ring groove to assist in squeezing the ring against the cylinder walls. I've managed to get a pic of it transferred here. I'm pretty sure this was a factory recommendation but I can't get to the file to verify, I did it on my 110 and my 140 came with it though I recollect more holes in the 140 (I thought 4 but could be wrong as it was 10 years or more ago).