As luck would have it, the Webra 40 I blogged about in my last entry is at least as old as the plane it was mounted in.
According to the wonderfully helpful Paul's Hobby Shop of Fargo, North Dakota, that old engine is designed to run on 0 to 5% nitro with 20% minimum oil content. The modern standard 15% nitro/18% oil was causing the engine to detonate and overheat, hence the loss of power.
No one - and I mean no one - in my area carries the stuff and I would have needed to purchase a case.
I have no idea whether or not that engine as four gallons of life left in it, so out it came and in went a lightly used Magnum XL .46 I had set aside for another project.
Same basic size (the crankshaft snout is actually a tad shorter) and weight, so in it went.
This engine was another prize from the same club raffle which went to a member who flies strictly electric. In fact, he was glad to give it to me since he had no idea what the heck he was going to do with it.
All I need to do is continue to help him out with his buddy box, which I am more than happy to do.
Tell you what, though: That Magnum revs like crazy, much faster than the Webra even with the tuned pipe.
I'd forgotten to mention in my previous blog that what might be a pesky little air leak was driving the idle setting on my ancient Super Sportster "castoff" absolutely bonkers. This morning, the engine started losing power in flight which, coupled with the weird idle issues, led to one very l-o-o-o-o-n-g landing with a broken prop resulting from it running out of runway. Basically, I was trying to bring it down in a hurry and it glided in hot at a private R/C airstrip I was privileged to fly at. The owner of the property had an old three-blade Evolution trainer prop which we used to get it back in the air. Not a whole heck of a lot of thrust with such a low-pitched prop as I'd correctly assumed and when it started losing power again, I knew it wasn't going to make the field, so down it came in the open desert before the runway. No harm at all to the plane, prop busted off a blade.
So, out came the engine this evening.
Which, as it turned out is not an O.S. 45 as I'd been led to believe.
It is an Austrian-made Webra 40. An old one at that, needless to say.
Off to see the Google wizard which in turn led me back here and over to Paul's Model Supply in Fargo, North Dakota. Apparently, Paul is an expert on Webra engines, so I e-mailed him a description of my issues.
I told him that while a new engine would be great, the model would lose a big chunk of that vintage cool.
Don't let me down, Paul!
Naturally, I'll share the progress right here on this very blog, so stay tuned.
Talk about fun; the former "castoffs" in my last post are not only no longer cast off, but are now proud additions to my fleet.
The 1/6-scale Cub - which might not be a Sig Manufacturing model after all - had been giving me trouble from the very start in regards to its landing gear. The sleeves which are supposed to hold part of the assembly together simply have no grab left in them and the whole works collapsed on the first takeoff attempt.
Ah, but the second attempt was a thing of beauty. She took to the air with real authority on a fairly windy afternoon. Straight line performance was terrific and that old O.S. 45 hummed like it was new. Throttling back let the Cub fly nice and gentle, but those old 45's like to rev, so it wasn't terribly happy, but hey, I didn't mind.
Not wanting to press my luck with the landing gear, I floated the Cub in for a landing and sure enough, one side let go. I was able to taxi back to the flight line with no problem. The flight convinced me to eventually finish the visual details such as the cowl, scale wheels and landing gear fairings. It's just too much fun to fly a Cub not to do this one right.
The real fun came when the Super Sportster hit the sky. What a rush! Loud and screaming fast with that tuned pipe, it ripped through the sky with little more than some left aileron trim. It pulled off some truly nice loops, Cubans, half Cubans and victory rolls with a lot more aileron response than I would have...Continue Reading