epeltz

I have a .46 Royal in a Great Planes SS 40 arf, that flys great. I have always wanted to know what the specs were but never had the paper work. I bought this from a person in my club, and it was brand new, never used, but had no paperwork with it. I understand they are not in business any more but thought someone here might have one and know its specs.

I am also asking because I am trying to compare a new TT.36 Pro with the Royal 46. I have a YA Extra 300s 30 size that is about the exact measurements and weight of my SS 40 arf, but wanted to use this TT.36 because I already set the mounts up for a .25 size engine, that I now know will not be good with this plane (Yellow Aircraft recommends using a .25-.32 2 stroke) So when I went back to the LHS I found that the .36 pro fit perfect with no changes other then drill new engine holes. If I try and go to a 46 size the mounts and there blind nuts need to be removed and reset. Would think I need to fix the old holes also with dowels and epoxy. I would also have to remove all electronics to fit my hand inside. So I am hoping to take the lazy way out. The SS is the same weight, around 5lbs and most of the time I fly this 1/4 to 1/2 throttle. Any help would be great.

Ed

LearjetMech

What specs do you need?

Ed_Moorman

My Feedback: (1)

The Royal .46 was basically a copy of the older OS .46SF.

By the way, a Tower muffler will give you some more power. I loaned one to friend who had the Royal on a Koas. It bolts right on and, even though we didn't check rpm, the plane was noticeably faster in the air. He also had to open the needle a full turn. Power takes fuel.

RJConnet

Look at the picture below, if yours is exactly like it what you have is a Leo .46 and complete specs are available at www.leoengines.com If it is not identical it is probably one of those imported by Polks Hobbies back in the 80's and heaven only knows what the specs are. [8D]

RJ

epeltz

RJ,

Thanks,

that looks just like mine, even says Royal vertically sown the side. I will look it up on the link you sent. Thanks again!

Ed

jaka

Hi!
Power is around 1,25hp at 16000-17000rpm........like all other sport 6,5cc BB engines.
Doesn't say much though.

Regards!
Jan K
Sweden

Ed_Moorman

My Feedback: (1)

The older Royals were copies of the OS .40 & .45FSR. People in my club even used Royal ABC cylinder and piston sets in their OS engines when the original liners wore the plating off.

Check the Mecoa .46. It also looks similar. There are probably a couple of places in China that are making all the engines except for the major brands.

fledermaus

I have a new-in-box Royal .46 that I picked up at a swap meet, and will be putting into my first plane (an LT-40) in a month or so. It is definitely the Leo engine (made in Taiwan) and I have confirmed this by email with Leo as well as inspection of their website. It is identical to the photo posted in this thread. I checked with MECOA as well and they said the Royals were either Leo or Thunder Tigers depending on type.

Anyhow, I have the original Royal documentation as well and it gives no specifications on rated horsepower or other performance, except to note that idle should be at 2600-2800 rpm.

The Leo website ([link=http://www.leoengines.com/page1.htm]http://www.leoengines.com/page1.htm[/link]) rates their 0.46 (visually identical to my Royal, Leo item 746 Model 46-EP ABC) as follows (your results most likely will differ):

Disp.(c.c.) 7.45
Bore(mm) 22.00
Storke(mm) 19.60
Output(Psor HP/r.p.m.) 1.43/16,000
Practical Range(r.p.m.) 2,000-17,000
Weight(g) 340

Can't wait to get this baby into a plane!

ace1991

I Have one of these engines and I can't get the thing to run full throttle with out the hot shot on it but I've changed the plug 3 times. Anyone know what type of glow plug is recommended for this engine.A3, long ,short, Idel bar no idel bar. Please help.....
Bobby

BillS

Send your mailing address and I will photocopy the instructions and mail them to you.

The instructions are:
GLOW PLUG
Use a long reach flow plug designed for R.C. use which employs an idle bar. Any of the major brands should give good performance.

Bill

BillS

If the engine will not run without the hot shot it is simply too rich.

What works for me is to take the glow starter off momentarily and if it starts to quit put it back on and lean three clicks. Repeat until it runs without the glow starter. Then adjust the top end to max (with tack) and back off 300 RPM. After the top end is set the bottom end probably needs to be adjusted again. One of the old timers at the field will be glad to help.

Report back if the problem continues to exist.

DualdudE

Hm..so they must be more or less the same as Topaz. Friend of mine has a Topaz .61, never seen such a big piece of junk. The carb is hard to adjust and it doesn't run reliable. And it only does 10000rpm on a 12x6 APC. Thats not much imho. Maybe i'm spoiled by my Irvine .53, that does 12000 or so with a 12x6 Graupner Nylon.

BillS

I have a Royal 40 and two 45’s purchased in the early 90’s. My findings are that 12x6 is way too much prop not allowing the engines to turn in the power band.

Also 10x6 works best on a 45 and a 6 lb airplane. An 11x6 might work better on a lighter airframe. Magically my airplanes get heaver with age.

A .53 size engine is sixteen percent larger than a 45 and should turn a larger prop.

Never seen a Topaz. It is certain you understand that it is hard to consider something junk by indefinite reference to an unknown engine.

Bill

BillS

ace1991,

The instructions for the Royal are in the mail.

The piston for a Royal has a hole on the transfer side and can be put in the engine backwards in which case there would be no end of operational problems. You might want to look in the exhaust port just to make sure the piston is installed correctly.

Bill

ace1991

Thanks for all the help!!!