When they get it right, thanks to many people on this forum that did their beta testing for them, then I might get one.

PlaneKrazee I guess that I need to read the last 10 to 15 pages of this forum to really know, but for a warbird not 3D style flying has the engine quiting issue been fixed or found??

Again, the DLE 30 does not quit in flight. Some have had issues, generally with pretty new engines, where they would quit after landing. Some have had issues where the engine would quit when the plane was picked up by hand and tilted. It does not stop in flight.

Giving credit where credit is due, the DLE 30 is a good engine selection that performs best after a prolonged break in. That time varies engine by engine but nine will be broken in after only a couple tanks of gas. Plan on a couple gallons of gas though I prefer to use hours as a more accurate time standard.

No, I cannot elaborate on the other engine design. You folks need to maintain some hope that DLE will correct their design deficiences and that Syssa will work out to be as good as they say. Ya'll gotta quit believing hp numbers without a dyno plot to go along with it though.

That picture got me more excited than I have been in a while

Pat must know something about that picture for he said that he didn't take it?

Prolonged BREAK IN come on TOM. Fix the intake as i have and issues are non existant. BOOM BOOM No more horse ...

Pat doesn't do that sort of stuff from the info he has given. He works for an independent contractor under a nondisclosure agreement. I did the same thing when in the service while working with aviation contractors, so I'm familiar with how it works. Pat appears able to give more hints than I was allowed to do.

I can't provide my employment status. Something I see blw understands.

Break in is a pretty easy thing to understand when you can visually see the changes taking pace via advanced monitoring systems in both controlled and uncontrolled environments. When you look at the picture that w8ye posted you might recognisze that a lot of engines get set up an a regular basis. Ain't no way I can go into what all they might be. Set up a thousand engines or more a year and you might, just might, develop a "feel" for what they need to complete the break in process. There's a lot more to running an engine, setting it up, and getting all the performance parameters correct besides setting the needles. A whole lot more.

Those that piddle with a couple of needles on the home garage test stands might think they know their engines. If all they have is a tach and a heat gun they are clueless. Sorry folks, but the facts and the truth of complete performance data can't be overshadowed with some silly and generally misunderstood rpm count. Even that fish scale thrust reading is corrupt since it fails to account for blade stall with the propeller. Static prop loading is a fools game where determining engine output is concerned. If you can't unload the prop throughout the engine's power band you really don't know squat. If that's all you have I suppose you can grade your engines based upon extremely limited performance data, but you won't be able to take advantage of accurate comparisons where engine purchase decisions are concerned. You'll be going into the process with about 20% of what you should have to make a valid performance comparison.

None of the above is proprietary, but is pretty commonly understood with most advanced propulsion techs and engineers.

However, those of us individuals who do not have dynos and O2 sensors will have to make do with a Glow Bee, fish scale, and our most important assets - sight, smell, feel, & hearing for it is not cost effective to have all the so called scientific instruments for maybe one or two new engines a year.

Concur, but argueing performance parameters with those that do.....

Hey if I can put an engine on a plane and have it preform the way that I want it to that is all that I need. This is a hobby that is for tinkers. I love to play with something and get it running to the best of my ability and have it preform in the air to my liking. I have a DL50 on a 15 pound plane and it is a rocket. That is why they make a left stick. I fly all types but perfer WW2 planes. And while I like them to be scale I do not like having JUST enough power. As for all the understanding of an engine from the inside out that is what designers and engineers are for. Still TOM keep up the good info. I have no problems listening and taking advise from someone that KNOWS what he is talking about when they give advise!!

Fixing the intake will not cure all engines, I did fix the intake. The problem with mine was the cylinder/piston tolerances were so far off that it died on landing from excessive friction when forward motion slowed enough. After I removed a little of the piston skirt all is good now. Extended "break in" (or wearing out) would accomplish the same thing, I'm not that patient. Not all engines have SPS, mine was excessive.

What does SPS mean ??

Karol

SPS, "shiny piston syndrome" as coined by the venerable Ralph Cunningham, refers to piston skirt wear in new engines from clearances that are a tad too tight at the bottom of the cylinder. Other than added friction fromtaking a while to make it's own clearance it doesn't seem to hurt anything that I have seen yet. This is the reasonsome of themhave benefited from a longer run it before expectingthem to "be all they can be"

That's mild compared to mine

RTK,

Can you post a good clear pic of your SPS?

MR G

That's something that troubles me greatly about this engine. I'm used to having 400 to 700 hour engines with zero to extremely minor light polishing of the piston skirts, and what there might be would be limited to the very bottom corners of the skirt. All the pistons still have all the original machine marks on them at 400 plus hours. The kind of tolerace issues in the 30 cost a lot of performce due to friction losses in areas where there should be no issue at all. Likely never develop any piston slap as the ring wears for sure, but you're wasting a lot of power in overcoming tolerance deficiencies. A lot like running an engine with a semi siezed bearing that can't float to overcome the friction. When the prop comes out of the flight phase of flight after the throttle back for a landing the engine could easily stop during the landing roll out.

Iagree, it did stop thoughafter it made it's ownroom andafter I was happy with them on atest stand,the ones I installed do not die on landing unless ofcoursethere are weeds in the way or the landing gear falls off.

I did not take any pictures, but if I ever take the cylinder off again I will. It still is a little tight when it warms up so I know there will still be marks. My SPS went further up the piston than those shown by Jody, and were much more aggressive in nature.

Something that puzzles me is the fact with the piston rubbing that much, why are we not seeing more seized up engines? One would think that has to make it run hotter than normal and thus push the piston even harder against the cylinder wall. As of yet I have not seen a pic of one that has seized up due to this.
I know a Dirt Bike or Snowmachine engine wouldn't run 5 mins like that W/O a catastrophic failure.
I laid some of it on the hard chrome cylinder, or maybe the piston material but alot of bikes and Snowmachine use similar setups., or even the type of oil thats used but people use so many different oils I can't really see where that would come in the pic at.
T.O.M. Jody any ideas on this Anyone ???

Hey Jody and RTK......nice photos Jody , I have a quick question does this SPS only occur at the Jug Tabs or is that just coincidence in the photo........ The piston skirt shows a lot of pinch at the vary bottom of the piston(you can see in your first photo) the impression at the bottom of the piston skirt is the same width and height of the jug tab. The SPS above that area looks like (particle drag) as the piston drags metal fragments up the liner it could form this unsual SPS cone shape, that is much higher on the piston than an actual squeeze point.

It does makes since to me low idle could become a problem depending on how much friction squeeze a particular engine has. The reason I ask is if its just the tabs making the contact on the piston, it would be a much easier to fix than an out of round cylinder bore. A bore thats to tight will extend the breakin for sure.

Normally I don't like to ask question on an engine I don't own...........I only have the DLE55 from Valley View, but I am looking at the DLE30 for a 25% Edge 540 that I now have a OS 160 on.

Just a thought

I think if you started a tight one up, went to full throttle while cold and left it there you might see what you describe. I've measured them and there is clearance before the SPS starts, it may be an alignment issue which could explain why some are worse than others. I sent those photos to the factory months ago when SPS was first realized, they said I was the first to bring it to thier attention and in the interpretaion I gathered they believed it to be alignment and said they would address it.

Good to hear Jody that the MFG is addressing the issue and it's possably alignment ............alignment pins would be nice.....of course they could just assemble with a alignment jig, but that makes anyone who disassembles it after the factory, in a world of hurt.

I don't think it will keep me from purchasing one now...........it seems only a few have this problem, and it will go away with a little more breakin, or a little polishing work on the SPS areas.

Captn,

Just for you I think I've found an excellent reason to use those Bowman rings. It may also relate to why I've not seen the same benefits you have.

I just tore down a 14 hour DLE 111 of mine. Overall I was quite pleased with what I saw. One of the best flame fronts I've encountered in a long time. However, as I've experienced with a couple of other Chinese engines, the rings had not completed the seating process after 14 hours. This is where the Bowman products could be a true performance benefit by seating much sooner than the ultra hard Chinese rings. The DLE 30 would prolly get some good performance out of them, along with all the other Chinese products if people switched out the rings right after purchase.

This may be why you've had such success with them. Typically I use products from the major manufacturers, or use products custom made by other vendors for specific purposes. In this arena the Bowman rings have not been able to provide an improvement over what I had. If you've been working with mostly "far eastern" products, the Bowmans's would likely have shown a significant inprovement over the stock products.

Knowing this is not the right thread for it, but anyone wondering about the rest of the 111's condition, overall it's just fine. A small void in the chrome in one cylinder, but it came that way. Even the majors experience this periodically. Everything else is just peachy.

Cyber,

It's difficult to get a DLE 30 all that hot. You'd have to be trying real hard. The intake design makes them run very cold. At least at the bottoms. Aside from that, I can't understand why they haven't siezed either in the extreme cases. There have been a few rather extreme wear engines at that, but they didn't sieze like one would expect. I know one of my Harleys sure did a fair number of years ago, and that was from just a tad too little clearance between the piston and cylinder after a new top.