OS_1-60_Setup

(much significant information came from Gene Maurice, who really helped me with the Perry and Pipe info! Dave Lockhart had a lot of insights on pipe vagaries! Many thanks, both of you!)

I've received many inquiries about mounting the throttle servo onto the Hyde mount beam itself. My current airplanes use a Hyde-type ARIA w/ integral nose ring mount (design limitation). This is a very reliable, inexpensive, and easy to do modification to throttle servo setups. Email me for additional details, if needed.

1. OS 1.60 - after break in with a 17 x 12, needle should be about 1 1/4 to 1 1/8 open. I used to believe "run the stock one until it gets rough"; RECENTLY, changing one that didn't have a lot of flights on it, I am convinced that you should replace it with the 2RS-SS6004 from Boca (Boca Bearing Page) before the motor EVER is run. It's the SS two rubber seal bearing. Replace it once, no after run needed, run dry at end of day, forget it. You will wear out before it does. Hint - install a SECOND "needle valve spring clip" on top of the original, and 180* to the original. This holds the needle VERY tightly, centered in the needle seat, and holds it's position no matter what.

2. Fuel - 15% nitro, 18% oil - don't run more oil, OR more nitro. Not needed. I add a skosh of Klotz "Benol" castor, about 1.25 oz. per gallon for "heat insurance". I've used Powermaster, Cool Power, Magnum, Ritches' Brew, and have seen practically NO differences. Except PRICE.

4. Pipes - The Aeroslave CF pipe, without a doubt, is the BEST I have run!! LIGHT, at 3.2oz, it has a quiet, mellow tone, and tunes identical to the Mac's. I highly recommend it!! I like the Mac's (and the clones I found) also, run these at 23 1/2 to 24" FOLLOWING the header/curve, measured FROM the glow plug. This will give you around 8200-8400, 17 x 12 prop or equivalent load. Not real critical, just don't get it too short.

The ES Composites pipe(s) from Ed Skorepa are ALSO very good, have the long, fragile stinger integral on the exit. Very high quality manufacture, tune very similarly to the Aeroslave. VERY nice pipes. 2C140S8, or M8 (his best seller, I'm told), and the 2C160L8 works too, although it is a HUGELY LONG tuner setup. Go with the M8 if there's a problem with tunnel length at all.

5. Pump - the Perry (Varsane) VP-30 is the one to use. Tap the backplate of the OS for crankcase pressure. You don't have to use the hard tubing for pressure; I've had good luck with the small diameter blue silicone stuff. You DO, however, need to wrap the pump body with some electrical tape so the nylon clamp to mount it will be tight enough. If you don't use the tape, the clamp will tighten down on the firewall (firewall is my preferred location), but still be loose enough that the pump will rotate, and then it will kink lines. Don't ask how I know that.

6. Header - Mueller is the way to go. He does custom shapes and dimensions to match your airplane. First class, high quality work. Just shoot him an email kgamueller@rogers.com

Coupler - Buy Mine! Right HERE. I sell an excellent, soft silicone coupler, and two steel spring clamps. Lasts quite a well, if not run overly-hot, and allows movement, which protects the header.

7. Tank location - not critical, in fact, I don't think it makes a difference at all. At least in all my setups it hasn't.

8. Filter - I put one IN my fuel jug (a riding lawnmower gas filter from Wally World), then an in-line Sullivan "Crap Trap" on the fuel jug pump OUT line, then one BEFORE the pump in the plane, but AFTER the place where I break the line from tank to pump. I recommend that, as it permits you to break the line to run the pump out at end of day.

Starting - First start of the day, it needs high throttle trim, but NO more, and a starter. No way around it, particularly if you run the pump dry (I recommend it). After that, bump spinner opposite to compression, she'll go.

Plugs are not a problem, they all work. The A3 and A5 OS give a little more rpm's, and cleaner transitions, but not worth the extra money. OS 8 is the standard, and lasts a VERY long time. Then, the REAL secret - Tower Hobbies 6 for $15 plugs. Made by OS, they are exact copies of the OS 8, last forever, and work fine. You will NOT be blowing plugs; I think I have the original #8 in the motor from a couple months ago, at least.

Be VERY wary of flooding. The pump is very effective, and if you spin it with a starter when not needed, you'll fill the head. Also - the lower end likes to be lean for a smooth 2000 rpm or so idle after it breaks in; don't make it richer, as that bogs the transition, and makes it too rich to start easy. This OS likes to start lean; AFTER that first run of the day.

Pump pressure - leave it alone at first. After you're running things, and you find the midrange a tad rich (likely, and highly-probable), then LEAN the pump about 1/2 turn. That's what I've ended up doing on all of mine. From that point - go fly.

Nose Ring (if needed) - I use, Andy Pollitt's [with modification - see the "Arresti Nose Ring page" for info]. They are very light. Visit his website http://www.countryworkshop.ca/planes/andy/home.htm and email him.

This setup will not screw you, or lay down on you, and a complete, spare EVERYTHING setup in your flight box is $300. What can be better?

The 17 x 12 APC is VERY fast, probably not enough load, that's why it's my recommended break-in prop. The APC 17x13 is slower by virtue of the extra load, little more drag. The ULTIMATE slow performance prop is the APC 15.5 x 12 FOUR blade.

Tapping the Backplate: Although there are folks who recommend drilling through the upper left backplate mounting screw hole with a 1/16" drill, I will not recommend that method, as for me, it leaves too great a risk of metal shavings (small though they may be) being left in the counterweight and bearing/lower conrod bushing area of the motor. Not good. Rather, I suggest that one simply use a DuBro 6-32 pressure tap and drill the backplate after it is removed from the motor (any place where there will be room to install the pressure fitting). Then, simply install the pressure fitting using some permanent-type Loctite, the washer that comes with the fitting, and make it snug. After the loctite cures a bit, use a dremel grinder wheel (or cutoff wheel) to remove the excess threads protruding on the inside surface of the backplate. DO NOT FORGET TO DO THIS!!!! Wipe everything off, and reinstall the backplate. Done. No risk of metal floating around in the motor.

Bob,
I have a couple of updates to your 1.60 page that I thought you may be able to use. This stuff has been verified on three 1.60 installations on three different airplanes.

Idle mixture adjustment. Screw the idle mixture screw IN (lean) 2 FULL turns from the factory setting, in addition to the main needle 1 1/4 turns from closed. This willl get you very close to the optimum setup.

Always mount the remote needle to the airplane, never the engine, and use two springs on the needle valve. Needle settings stay very constant, and the needle wears better also.

Use LARGE, not medium, fuel line everywhere from the clunk to the carb. Use larger brass or aluminum outlet pipe from the tank. Use clips or tiny tie wraps and fuel line over fuel line to hold things on the various fittings.

Never, ever, use a starter, even on a new engine. Before you start the engine the first time for a day of flying, AND BEFORE YOU CONNECT THE GLOW PLUG CLIP, open the throttle fully, choke the engine with your finger over the carb for three pull thrus. Fuel WILL dump out on the ground, so have a rag handy. Now close the throttle to your normal low throttle flying setting, attach the glow plug clip, and flip the prop backwards. Will usually start in 1 to 3 back flips. After the initial run of the day, start it at low throttle, backflipping once, and it will almost always start on the first flip. Really POs the YS bunch!

Once the engine is broken in, I lean the pump 1/2 turn.

I use OS F plugs with great success.

I've had to deal with someone screwing up his engine by not getting the pressure fitting absolutely flush with the backplate, the connecting rod hitting it, and filling the case with shavings. That is why I recommend a 1/16" drill thru the upper left backplate screw, and the 1.60 FI pressure tap. I stuff the engine with oil soaked paper towels in the vicinity of where the drill will come thru, and drill the hole
with the engine pointed straight up so the filings drop out. Never had a problem.

I usually setup the motor on an engine stand with the header, pipe, and regulator, before installing it in an airplane. Makes it much easier to setup, and the settings carry over to the airplane, usually without
mods.

I use 15% Cool Power or Omega with equal success.

I'm still using Lockhart repitched 3 blade APC props. The newer props have a larger hub, and fillets between the blade and the hub. APC will exchange old for new at no cost.

Jon Lowe


The "First" version of the beam mounted throttle servo, a JR 281	The "Second" version on a HYDE mount, using an HS-55	The top view of the servo mounted on the Hyde mount rail.