EASYTIGER

My Feedback: (119)

In all my years of dorking around with engines, I have never heard of such a thing. Did you invent this yourself? Seems like a long, long way around of determining if you have a leaking head or a worn piston. What about thermal expansion? That does not figure into things? Rings? Oil seal?

EASYTIGER

My Feedback: (119)

It's just kind of funny.
You would think that since the seller has close to 1000 positive feedbacks over the last year, all from selling Russian model airplane engines, including several hundred of these UCKTAMS, with ZERO complaints, maybe there is nothing wrong with the engines?

Maybe you should not beleive everything you read on the internet?

I have run the MARZ and MAP and Silver Swallow and that kind of thing, they all ran.

Maybe you have insufficient oil content or something. What fuel did you use?

ptulmer

My Feedback: (5)

Easytiger,
I don't see anything funny about it. Most folks would leave good feedback when they receive the goods. After all, that's what the feedback system was originally for. You degrade two experienced modelers, not including myself and other owners, and disrupt the original intention of this thread. Do you have anything to add or will you continue to be a nusiance?

EASYTIGER

My Feedback: (119)

Add? Nope. Enjoy your engines.

Anybody else "dunk test" their engines?

ptulmer

My Feedback: (5)

Yep, me. Guess what. It works. I've used it on three engines now. One good one for a control.

ptulmer

My Feedback: (5)

All right, back to work. Here's a couple of pics of the engine parts. Look at the bearing. You can see daylight around the balls. Bad for holding pressure in the crankcase and leaking fuel out the front. Can I replace the front bearing with a sealed bearing?
It's well made and thoughtful in design. It's a shame the details were missed, but CP's right! It's worth forty bucks right now, if I can get it to run later.
I hooked the fuel pump up to the venturi and blew out the garbage in the holes. After that it would burn a prime off, but would not stay running. The piston/liner fit needs some work, and the leaky bearing needs to be sealed up. It might be ok after that. Maybe tapping for exhaust pressure too.

Big Al-RCU

Gee Ptulmer, we might have a copyright infringement case on our hands here. Some years ago the company that I'm retired from was having a hard time finding the source of leaks on the aft manifold of a large rocket engine thrust chamber. The usual method was to pressurize and use a soapy leak detect solution but the configuration tended to hide the leaks. A buddy of mine went across the street to Topanga Plazza and bought a Kid's inflatable swimming pool. Filled it with water and dunked the pressurized chamber and of course the leaks were readily apparent. But heres the rub, we incorporated this into our checkout procedures and since this was a govt contract and is documented we may have to blow the whistle on your illicit procedures.
Al
PS Before the copyright police start to complain. Good Grief Guys! Just Kidding!
al

combatpigg

My Feedback: (3)

Between those 2 engines, there has to be a runner. The bearings wont provide the seal, no matter which style they are, the air seal comes from a close tolerance fit between the crank and the case in the area between the bearings. That's why GLEN suggested bushing the crankcase right in front of the rear bearing, to establish a seal off. We don't know yet if this is the problem, but the dunk test will reveal air bubbles out the front if this is the case. Wait, did you already check this? Anyway, I learned this trick from a web site that was about converting chainsaw engines to airplane use. I thought it was pretty clever, and I have used it with everything from a HUSQVARNA 50 to a COX TD, and it works everytime. The cylinder "leak down" test is just fundamental "AUTOMOTIVE 101", it doesn't allow for thermal expansion but it is a place to start because gouges don't disappear when the engine is cold. If I ever get to the end of a long string of "to dos", I could bush those cases, but to be honest, there is quite a waiting line already! A special cutter would have to be made that pilots on the case journal, and has a step built in to cut a clearance notch for the bushing to be pressed into. The bushing would have to most likely be custom made, and inserted in the heated case, using the crank as the insertion tool.

Dan Vincent

PT,

Your second shot is a wealth of information.

OK...look at the drum rotary housing. See the rectangular window? That should line up with the vertical slot in the front of the crankcase, opposite end of the exhaust.

This is a car setup, where the drive and exhaust are on the same end.

If you look at the case you can see how thick it is in the area where the intake window should be shooting mixture into the case.

If you want to run this in airplane configuration you may have to approximate the channel in the bottom of the case, on the exhaust side.

Hope this isn't too confusing.

BOCA bearing may have something that will replace the Russian item.

Schu

My Feedback: (5)

Ok Guys,
I decided to run the engine again last night after I talked on this site and here is what happened. I had a APC 7x4 on it- what I had close at hand- and 15% fuel w/ syn oil about 20%, and it started w/ a little priming w/ my finger on the carb. I am using a pressure nipple on the tuned pipe- got the location from checking out some of my other pipes- and this helped alot. It ran the best at about 1/2 throttle- I think my carb throat is to big - and I was only able to get about 12,400 and it never got up on the pipe. I am going to take the carb out and try again in the std setup and see what it does w/ a smaller prop. The seller told me that a 6" is the correct size- didn't say what pitch. I noticed that I had to apply the heat to the plug till it got heated up before it ran well at all and if idled down it would sometimes just shut off unless I applied heat to the plug. Any ideas to try for better running as I am all ears- I know how to run engines ok, but I am no expert like some of you- no matter what CP says- maybe I just got lucky to get it to just run. Dale

EASYTIGER

My Feedback: (119)

Yes, along with every tire shop in America.

EASYTIGER

My Feedback: (119)

I see. So you made it up. There are a multitude of reasons why it's not appropriate for model airplane engines, but you keep doing it yourself.

ptulmer

My Feedback: (5)

CP, no I haven't started on this particular engine. Putting the cart before the horse, so to speak. After my previous failure I wanted a grocery list to start with. Plus I'm waiting for the wife to leave so I can bake engine parts in her new oven.

Dan, wouldn't doing that open the crankcase up to the outside in the exhaust port? Or do I stop short? I'm I thinking wrong? Maybe you mean in the bottom of the crankcase and the window should point down? I'll take some more pictures this afternoon to show both sides of the case.

Schu, You got one with a throttle?! I think my venturi is a little oversized also. Not positive, but it's something to watch for.

EASYTIGER

My Feedback: (119)

You didn't just get lucky, you were wise enough not to beleive the nonsense you read on the internet.
These engines should run. All the other russian ones I have owned did.
My two worthless cents? Yes, ditch the carb. It's a venturi engine. Increase the nitro and reduce the prop. It's a 26k engine, it's not going to do bubkes until it gets up on the pipe. And give it some run-in time before expecting those kinds of numbers.
Don't expect it to take a carb and idle properly, it's not set up for that.
I'm not sure if the porting is a problem like Dan says, I find it difficult to beleive that they are providing the wrong crank, but it's possible, I suppose.

ptulmer

My Feedback: (5)

Please, share your wisdom with us savages, Oh Great One.

I thought he'd picked it up from a website converting chainsaw engines... Well, let's see. You blasted CP, Glen, and ME. Watch out Dan, something tells me your next. Don't worry though, you're in the best of company.

EASYTIGER

My Feedback: (119)

I think glen was talking about what it takes to make a useful combat or speed engine.
CL speed freaks are an odd breed, they have different standards entirely.

So...if your front bearing is totally sealed...it's totally unlubricated, too.

Tim Wiltse-RCU

Patrick,

That is the same thing I found with mine. It came with the car configuration with the intake and exhaust on the opposite ends. I changed it around to RIRE. In doing so I too noticed the intake port that was blocked by the venturi plate. I just tossed the parts into the box at that point. On mine I had a locked up piston so in taking the head off broke one or two screws, plus the screw holes didn't line up when I switched the ends around[:@] Just a real pile od junk. There is just to many other engines of this size that can turn a bigger prop and without the TON of weight and they don't need to be rebuilt to do so. The only thing worth anything is the pipe. If anyone wants my engine to mess with send me $15 and I'll send the whole mess out to them.

Later,
Tim

Schu

My Feedback: (5)

PT,
Yes I installed a large throat car carb hoping for some type of throttle out of the engine- I will try to go back to the original layout w/ venturi as per my thought and ET's advise and use a APC 6x5 0r 4 or something and try for some rpm's and see what it does w/ the pipe.
Tim- mine must have been set up for planes as it came set up for that unlike yours. I will say that you need to be real carefull w/ the screws as you work because they are very soft. Dale

EASYTIGER

My Feedback: (119)

6x5 SOUNDS about right. But I'm just guessing. That's where I would start with a piped 09.
Pipe length is another issue.
I don't know how familiar you are with tuning pipes, but:
The pipe has to be tuned to the engine, atmospheric conditions, and fuel.
Looks like those rings around the front of the pipe coupler are there for you to cut the pipe down until it starts working?
Many other engines have similar marks on the header or pipe.
Most Russian flyers use FAI fuel, zero nitro, so the box stock setup may be for that, or no tuning at all.
You need to (after you get on the right prop that lets the engine spin up) select a fuel that you will use(your guess is as good as mine...I suggest 25%, or reading the instructions and seeing if there is any info there), then run it and keep shortening the pipe until the engine peaks, then back off just a little bit to let the thing unload in the air.
There is a very remote possibility that the pipe is already too short, but I doubt that.
Doubt it will see the north side of 15k until it hits the pipe.
IF you get everything peaked, then maybe you can try the carb and see what happens. You will probably lose some top end, but that may not be a big concern. Doubt you will get a useful throttle response, but you might be able to get an idle low enough, somewhere below 5k, so at least you can land. But remember the thing was just not set up for throttle, so keep your expectations low.
As far as screws go, cheap screws are common on much russian machinery, yep, make sure your screwdrivers fit accurately, that goes a long way towards not chewing them up. If you have better replacements, use them, because cheap screws stretch as they heat up and contract and cause loose heads.
Sounds like fun, keep at it. $40 bucks including shipping, seems like a fun little thing.

EASYTIGER

My Feedback: (119)

Just as a general rule...
Pipe tuning is not OPTIONAL. You cannot just bolt on a tuned pipe in a "one size fits all" configuration. It will be a comprimise in performance.

ptulmer

My Feedback: (5)

More general info-
Mine came set up as an airplane engine. RIRE. The ad said it should reach 26k rpm, so that may be the goal for propping with the right load.

Tim, if nobody takes you up on the offer, I'd be happy to try to fix it for you. I'll be sticking a package in the mail to you tomorrow. If I'm successful with my engines, just stick yours in the return box and I'll try my darndest. I don't want another parts engine though. Don't even THINK about it.

ps. a sealed bearing is permanently lubricated. Small amounts of castor would not be necessary.

Dan Vincent

Guys.

I may be going out on a limb here by saying I believe all of these 1.5 engines were built in a race car configuration. What I'm hoping for is someone to prove me wrong and show me a case with the intake chute on the exhaust end of the engine.

I have three of these engines, 2-glos and a diesel. The Diesel head is worthless. The contra-piston was so tight on the diesel, I had to loosen it up...trouble is it's too loose now.

For me, the entire intake tract from the rotary drum window up in to the case should match in one smooth flow. Reversing the case without grinding a bit will not give a smooth flow and should restrict. The Crank should be the same regardless of which way you put the case.

Seems to me that once the fuel mixture enters the case it is more or less atomized anyway so it will reach the combustion chamber.

I want to run one in the car set-up and record the RPM, Then reverse the case and get another set of readings. Then, take the engine apart and dremel tool grind the case to match the port on the rear drum housing.

After that I will try the Russian pipe and a CS .09 pipe I also have.

Changing out those screws to socket head is another mod I will make. Have to go by a specialty screw shop.

Don't know when I'll get around to it but sometime within the next month....I hope.

combatpigg

My Feedback: (3)

Man, anyone who thinks he can "diss" GLEN DYE is really,"OUT THERE"............I was in a GO-PED building mode a couple of years ago, and I had some 31 to 50 cc engines at my disposal that ran inconsistantly. After snooping around the internet, I was amazed at how much info there was/is out there about this sort of thing. Barstool racing, couch racing, power tool drags, you name it! Armed with the basic troubleshooting info, I was able to get these engines up and running for $10 each or less. Anyway, the principal is the same with all 2 strokes, a good crankcase snout seal is a fine line between friction and film strength of the oil against either the hard parts, or the rubber seals. Some model engines can throw quite a bit of fuel/oil out the front and get away with it at high rpm. I think running bladder pressure helps here because ample delivery is usually guaranteed. The venturi should have 10% less area than the largest opening in the crank for good needling. For a disk valve, I'm not sure what the wisdom is there.

Japanman

Tim,
I dunno if you have recieved any p.ms from any interested partys, but I`d take that engine with a smile for $15 as a "Kit engine" with a lathe it seems just up my alley. Then again, as P.T has already offered to fix it for you, you might want to take him up on his offer.

J.M

combatpigg

My Feedback: (3)

Hey JM, as soon as PATRICK convinces his wife that they need a lathe, he'll have one too!