RE: Prop on a car engine
Testing a car engine for performance should be done on an inertia dyno. It's the quickest way to get a curve through the entire RPM range. A prop will only give data for one speed. Do the math and make sure your flywheel is safe at the speed you want to run it. The clutch will not disengage until RPM drops below engagement speed. This is a simple fact of life with a centrifugal clutch. You can use a one way bearing to allow the flywheel to overrun, or put a brake on the flywheel and use it, to prevent the engine from being run so fast with the throttle closed(read no oil flow). Props can be used, but then you're talking many test runs to generate a curve. Who uses a dyno? Mostly the engine tuners. Google and youtube turn up plenty of information about inertia dynos. An inertia dyno needs some electronics to get the data. At the bare minimum a rev counter with a timer, the rest can be done by hand.
Posted on: 2/2/2012 6:47 AM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10940003

RE: BOLD PREDICTION: Zenoah will eventually follow FUJI IMVAC down the crapper
[quote]ORIGINAL: gkamysz Let's keep this thread in mind about 6-12 months from now. This discussion should be much more interesting about that time. [/quote] The time has come. [image]http://www.dieselrc.com/x/other/popcorn.gif[/image] http://www.rcuniverse.com/forum/m_10938557/tm.htm http://www.horizonhobby.com/webapp/wcs/stores/servlet/SearchCmd?searchKeyword=ZENEP&filterTerm=&
Posted on: 2/1/2012 10:34 AM by Author "gkamysz" in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10938635

RE: E85 in the OS Bio-Ethanol engines
He's thinking of the Enya Gasoline glow plug engine. It's been done with E85 and regular hot glowplugs. Just get several plugs and try, even four stroke plugs in a two stroke. Good luck. They don't import the BE engines to the US. I thought the oil in OS bioethanol fuel was castor, but maybe it's some synthetic.
Posted on: 1/26/2012 8:17 PM by Author "gkamysz" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=10929868

RE: Oil holes in conrods?
This was an airplane engine. gkamysz
Posted on: 1/20/2012 9:18 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10917251

RE: Oil holes in conrods?
was a mess. I bought it for the carb. gkamysz
Posted on: 1/20/2012 9:17 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10917015

RE: Oil holes in conrods?
see that I was wrong. gkamysz
Posted on: 1/20/2012 9:15 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10916203

RE: Oil holes in conrods?
in the passage right at the hole. I have to think this would assist in collecting oil. gkamysz
Posted on: 1/20/2012 9:14 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10915313

RE: Oil holes in conrods?
there are answers if you want to find them. gkamysz
Posted on: 1/20/2012 9:13 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10914431

RE: Oil holes in conrods?
BTW, Earl, thanks for the photos. I was sure somebody had used a groove like that. You must have a pretty impressive engine pile. I'm trying not to add to my pile lately. gkamysz
Posted on: 1/20/2012 9:11 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10914148

RE: Oil holes in conrods?
on it? Scraping off the crankcase walls? gkamysz
Posted on: 1/20/2012 9:11 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10914140

RE: Oil holes in conrods?
quote: ORIGINAL: littlera All I know about con rod oil holes is my experience that if they get plugged up, the conrod bearing will seize on the crank pin from lack of lubricatiion. This is exactly what happened to my Sait .50. I had to replace the crank and conrod. I always worry about that and never run an old four stroke without cleaning the insides.
Posted on: 1/20/2012 9:09 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10913722

RE: Oil holes in conrods?
Pe, have you seen the cranks with an oil feed hole drilled through the intake passage to the crank pin? This was once popular, but I'm not sure anymore. I didn't think it was the best design as the hole exited the crank pin right at the top at 12:00 when at TDC. Of course this only applies to front induction. I might have a Picco crank laying around.
Posted on: 1/20/2012 9:08 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10913267

RE: Oil holes in conrods?
This is not something 99% of us even need to be aware of, let alone think about. High performance engines have trouble with lubrication. Sport engines might but usually it's due to the lack of an oil hole. Adding one usually fixes the problem. Team race engines are always fighting lube issues because the fuel mix is light on lube. 10% oil in an engine turning 25+RPM making over 1kW? People get their panties in a wad when you tell them to make fuel containing 25% oil and maybe even synthetic =:-O for their mild sport engine. It's interesting discussion none the less. How do you observe which way oil flows through the big end bearing in a model engine?
Posted on: 1/20/2012 9:05 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10911471

RE: OS 40FP with DDD
Dave, if the engine is set correctly, I agree. Our diesels are usually set near detonation on the side of normal combustion. If you're conservative on settings, the engine will be fine. Not every engine is obvious about being over-compressed at low RPM, because it doesn't always result in knock.
Posted on: 1/19/2012 9:38 AM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10917070

RE: OS 40FP with DDD
[quote]ORIGINAL: buzzard bait But you will run LOWER compression (and lower rpm) using the big prop, and HIGHER compression (and higher rpm) using the small prop. So why would a big prop be more likely to break the crank? Other than prop strikes of course. Jim [/quote] There is less margin of error to get the actual ignition timing right. When the engine is turning slower it's much easier for the pressure rise in the cylinder to be very fast and this leads to high forces on parts. If it were running faster the piston is already traveling down and expanding the gasses and reducing pressures. The amount of time for combustion is almost fixed, while the the pressure curves are very different and different RPM(non throttled). If the compression ratio and mixture settings are just right you shouldn't have any problems. But, with a two stroke it's hard to tell that you have them right. My four stroke diesel conversions make it obvious they're not happy very quickly, especially when loaded with large props. There is a very audible knock, the get progressively worse. Two strokes and smaller engines are not so obvious, when ignition timing is advanced beyond ideal. Greg
Posted on: 1/19/2012 8:23 AM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10916948

RE: Mini F-16 vintage project consideration
OK, I see now. I've never seen a recessed Kress rotor. If you don't have a convenient source for the spacer, contact me. I'd make the rings from 1/8" aircraft ply. Leave a short lip on the ends of the shroud to allow a sleeve to slip over the fan shroud. This will make connecting the ductwork much easier. Greg
Posted on: 1/17/2012 7:26 AM by Author "gkamysz" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10913259

RE: Mini F-16 vintage project consideration
Did you get the venturi interference sorted?
Posted on: 1/16/2012 6:27 PM by Author "gkamysz" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10912479

RE: How to keep castor from seperating in cold?
Typically the answer is synthetic oil. How long has your castor been sitting around? I've had problems with old castor.
Posted on: 1/16/2012 9:08 AM by Author "gkamysz" in the forum "RC Fuels"
http://www.rcuniverse.com/forum/fb.asp?m=10911573

RE: Reaction to Diesel Fumes...?
I get a reaction to the oil in fuel, I think. It seems to happen no matter what kind of engine I run, glow, diesel gas, E85, plus whatever else I've tried. Usually only when there is no wind. my sinuses get stuffy and I'll end up with a headache, hours later or the next day. I doubt there is IPN in Davis fuel, probably octyl nitrate. You could always ask for an MSDS to take to your doc or research yourself.
Posted on: 1/16/2012 8:25 AM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10911485

RE: Mini F-16 vintage project consideration
I just typed rk709 and rk-709 in the google image search. One is from a french site the other from a classified ad here at RCU. Looks like the section didn't make it.
Posted on: 1/12/2012 9:21 AM by Author "gkamysz" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10905061

RE: Mini F-16 vintage project consideration
You do have the prop driver on there right? Props would hit the venturi too? This is what the parts looked like. A couple photos from the net. There were a few versions it seems. Some with orange rotors, some with blue, some with the preformed head recess in the duct, some without.
Posted on: 1/12/2012 7:58 AM by Author "gkamysz" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10904930

RE: Mini F-16 vintage project consideration
If the 8-32 will hold a prop it will hold the fan. The torque and power output of the engine is the same. I'd start with a simple bushing and see if the fan mounts square. What are you drawing with? How many of the rotors have aluminum inserts? I think it will work well. Greg
Posted on: 1/11/2012 12:03 PM by Author "gkamysz" in the forum ""1/2 A" & "1/8 A" airplanes"
http://www.rcuniverse.com/forum/fb.asp?m=10903730

RE: Made my own glow fuel today
[quote]ORIGINAL: cheezer1222 Another question: So that I don't have to dump the 12% acetone batch that I made, can I add gas and run it in my gasser (baja)? Or am I opening up a whole new can of worms? I know in the gasser to glow forum, when it came to mixing methanol, they had talked about the possibility of carb diaphragm swelling, fuel line swelling, etc. I'm not against dumping it, I just think it would be nice not to waste it. [/quote] Yes, can of worms. Just chalk it up to experience. I have about a gallon of strange or wasted fuel mixes and I make small 100-200mL batches when testing different things. Most of it just stuff that was left in the tank from test runs and needed to be drained before the next run.
Posted on: 1/11/2012 9:49 AM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10903500

RE: Made my own glow fuel today
[quote]ORIGINAL: cheezer1222 As far as the model lube oil goes, will it not mix as long as there is any methanol in the mixture? Because I was thinking I could try a small batch that looks something like this: 25oz Batch 48% methanol 28% gasoline 4% acetone 20% oil (80/20) [/quote] If you add that much gas the model lube might stay in solution. The trouble is your fuel probably will not work well. Gasoline will further reduce the power output and require even leaner needle settings. The needles will be critical and midrange probably fat. I'd simply make a batch of methanol - Benol and be done with it. Greg
Posted on: 1/11/2012 8:20 AM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10903357

RE: Made my own glow fuel today
Chances are without the 12% acetone you already have in there all of the Model Lube would be at the bottom of the jug. I can't think of anything you could add that would result in a useable fuel. Yes of course, Benol is fine.
Posted on: 1/10/2012 7:53 PM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10902773

RE: Made my own glow fuel today
[quote]ORIGINAL: cheezer1222 Another update: I notice that some of my oil seems to kind of settle/congeal on the bottom of the bottle that I use to fill my vehicle. I wasn't expecting that. I use klotz oil (model lube (synth) and benol (castor)), and from what I had read, klotz was one of the better oils to use to keep things from coming out of suspension. [/quote] Klotz Model Lube is not for methanol!!! You should be using Origninal Techniplate for methanol.
Posted on: 1/10/2012 6:09 PM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10902609

RE: Made my own glow fuel today
Acetone is not a replacement for nitromethane. It is said to help idle without nitro, but that's all. The make that car engine run well without nitro in the fuel the compression ratio must be increased. If you don't increase compression ratio you'll probably need a hotter plug. The needles will be set more rich when tuned for fuel without nitromethane.
Posted on: 1/10/2012 4:08 PM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10902389

RE: Why?
Ed, you posted this question in the wrong forum. You're preaching to the choir. Ask the guys that don't run diesel why they choose not to. Greg
Posted on: 1/9/2012 6:12 PM by Author "gkamysz" in the forum "Everything Diesel"
http://www.rcuniverse.com/forum/fb.asp?m=10900839

RE: OS 52 4 stroke
Sometime people think there is a problem when they see there is no gasket on the intake manifold at the head. It is not needed. Also all OS FS will leak a little under the valve cover. I make paper gaskets for mine. Again, nothing to worry about. The 12x6 is a good prop. 11x7 if you want to go a bit faster. Was the Waukesha swap any good? I missed it. I need to make it over to the Kellner's this year too, the club usually make a field trip every other year. Greg
Posted on: 1/8/2012 7:44 PM by Author "gkamysz" in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=10898913

RE: SMALL DISPLACEMENT FOUR STROKE GLOW TO GAS CONVERSION
RCV uses the same setup for the own spark ignition engines. Nothing to worry about.
Posted on: 1/8/2012 7:28 PM by Author "gkamysz" in the forum "Engine Conversions"
http://www.rcuniverse.com/forum/fb.asp?m=10898894