QuickTalk 28 - QUICKIE HINTS
- Category: Q-Talk Articles
- Published: Monday, 30 June 1986 07:11
- Written by Jim Masal
- Hits: 1096
GLOBAL ENGINE UPDATE from Jim Masal:
After more than 4 months, Global has finally sent Bob Giles his engine. During flight-testing at the 23 hour mark the steel tube engine mount broke behind the upper left engine attachment. Giles re-welded it but the next week the upper right attachment of the engine case itself fractured. Global has had several similar instances so Giles sent the engine in for a re-weld and the mount beef-up treatment Global is giving all their engines now. Global also welded up a new steel tube mount with slightly larger and stronger tubing. Global's Gene Smyers examined the engine to see why we weren't able to get 3600 rpms or more, and in the process of tinkering, he made some changes that boosted the hp up near 40 on his dyno test. For example, it was realized that the oil pump didn't need to run so hard since it was now only pumping for half an engine. It was shimmed to run at half capacity and this generated less engine heat and spared more power for thrust. 30% larger intake and exhaust valves were installed, a stock cam was fitted, the heads were polished and ported and deck height was reduced to .040, and 3/8" larger exhaust pipes were added.
The revamped engine was installed and flight-tested on June 29. Static rpm was up from 2600 to 3000 and in the cruise condition rpm was up to 3250. Still not as expected but a different prop may be the answer as the current one has been shortened twice. Ed Sterba, who, incidentally, is a very helpful and reasonable prop maker, is now carving Giles a 52x32. This engine is running 30-50% smoother than my vibrating Onan, and on a 100 degree day at 600 lbs gross it climbed at 425 fpm.
Global engines currently are running about $2100-$2200. There is an alternative in the form of plans describing how to cut and build a 1/2 VW. This can probably be done for around $1,000 depending on ability to scrounge and the machine shop work. Both Morry Hummel and Kite Industries offer plans (see ads in SPORT AVIATION) for $15. I have both sets and each has something worthwhile that the other does not so you should get both sets.
From Craig Wiermaa
I purchased an Onan Service Manual from the company in Minneapolis, MN. I don't see how you can run an Onan engine without it. Call Onan at (612) 574-5000 or 536-3500.
I can't say enough about cooling. I think all Onan owners need to see an industrial application to appreciate how tight and exacting the ducting and baffling of the intakes and outlets must be. These factory engine shrouds are air tight and sealed with silicone. Openings are carefully sized to fit. Every owner who is willing to place his life in the hands of this engine should see what it REALLY takes to keep these cool in an airplane installation.
ROTAX ENGINE NOTES from Jim Masal:
I recently talked to Jerry Olenik of Green Sky Adventures, 2377 Creamridge Rd, Orwell, OH 44076, (216) 293-7688. These guys sell Rotax engines, and just for your thinking cap, here are some prices (add $225 for the gear reduction drive). Rotax 377 = $1144; 447 = $1174; 503 = $1325 (dual carb). Jerry says they operate an authorized overhaul and service center and that the biggest reliability problem they see is stuck rings due to "stale" fuel or poor oil in ultralights, which don't fly regularly. He speculated that in a Quickie with a closed fuel system and being hangared this problem might not be as serious. Use fresh fuel, is his strong recommendation.
From Hans Vos C-GGLC, Hamilton, Ontario, Canada
My 285 lb Quickie was completed in Oct. 84 without major problems. Performance is close to QAC specs. I did not make any adjustments or alterations to the airframe or engine for the first 50 hrs at which time the valves needed adjustment.
Flight characteristics are beautiful; landings still demand my full attention and a crosswind much over 5 mph I consider "chancy", although I haven't lost control (yet)! Total flight time is 71 hrs; total landings (of which I only consider 2 as beauties) 49; only 7 flights less than an hour's duration. Flights were made between 25 and 80 deg. F and one flight was cut short due to icing inside the canopy. I've made no flights in rain, but aborted a takeoff after going through a puddle on the takeoff run. I usually cruise at 2500'-5500', 90 mph and 3200 rpm since the engine sounds best here.
You can order a PDF or printed copy of QuickTalk #28 by using the Q-talk Back Issue Order Page.