rc-plane

I might have missed this but, Did you buy the motors at the same time?

JUGFLIER

About three months apart, but they were put into service at the same time and have virtually the same runtime.

RTK

My Feedback: (1)

You can run it at that, but I would recommend a different oil all together. I used to use that a few years ago, (run at about 70:1) and never had any problems, but the deposits were quite hard when compared to other oils.

hutchi

Thanks RTK so what oil do you recommend for the 115 with just over 10 gal thur it

RTK

My Feedback: (1)

There are lots of good synthetics and conventional oils out there. Lately I have been running Pennzoil air cooled at a little lower than 40:1, but if you are having good luck running what you are and not having an excessive carbon build up, what the heck. If it ain't broke don't fix it

JoeAirPort

My Feedback: (41)

Redline, Yamalube 2R, Bel Ray, Mobil 1 2T are good synthetics (or semi-synth). Pennzoil and Stihl are really good petro based oils.

manofsteel

My Feedback: (2)

I am a certified engine mechanic and I can tell you that DA got a bad batch of rings for that to happen after all that I read about you providing that you both bought the engines about the same time. I have the DA50 that is over 2yrs old with no problem and I use 50/1 ratio. Never would I go much more. My newest is the 3MM53 engine which I feel is a great engine! All of us flyers should have DA make good for both engines and planes due to this problem, as long as it was NOT a pillots fault. If they do not help out then we should not buy their engines. Saying that, this should stand with all engines manufactures. That's just my opinion.

dbcaster

I am sorry but this is a rediculous post. Why don't you let DA get a chance to see the engines before you make a statement like we should all not buy their engines. I am sure you like everyone else makes mistakes. Are you o.k. with someone saying, if you have a problem with an engine you work on. No one should do business with you? When was the last time DA did not stand behind one of their engines? Thousands of DA-50's have been running without breaking rings including yours. One person breaks a ring on two engines? I would question what was being done to the two engines that is different than the thousands out there that are o.k. before the engine itself. Either way DA will stand behind it.

JUGFLIER

Frankly, I am reserving my judgement until i hear something from DA. The engines were shipped Tuesday and i was told by the man at the UPS counter that it would get there on Monday. I should be hearing something after that.

That said, I have been talking to people i know who have DAs. We did not have a cooling problem with either engine. The engines were not being abused or used in any manner that would even be remotely construed as in consistent with what they are designed for. We were swinging props well within the reccomended range. The oil was properly mixed for the ratio we wanted to achieve, and the gas being used was mixed 6 days before and was kept in a trailer. Also these engines were not too lean.

With all that said, i have narrowed the failures down to two possibilities.

1. Defective rings and or piston.

2. Impropor oil and or mix. I am leaning heavily to the possibility as stated by someone that Amsoil at 50 to 1 may produce excessive carbon build up behind the rings. I think when i hear from DA this could possibly be the culprit. My philosophy has been if a little oil is good, then a little more wont hurt it. Wella little more just might.

dbcaster

That is really my point. There is no reason to speculate until you hear from DA. My guess is, they will take care of it either way and you will pay little to nothing. Not to start an oil war but Gerhard at 3W said every engine he gets that has run 100:1 Amsoil is severly carboned up. Let us know what DA finds.

catfish2

My Feedback: (43)

I would personally add a 3rd posibility to the list. Bad gas. As in bad from the pump, not from storage. Have you run your mixture or even straight gas from the same source in any of your other equipment?

JoeAirPort

My Feedback: (41)

DA will totally take care of you. Not to worry.

I think because of that certified mechanic's harsh attitude we should not have him work on any of our engines. I hope he has a sense of humor. I am kidding man.

JUGFLIER

Catfish,

Love the name by the way. The gas was mixed 6 days before, it was bought at a shell station. We ran about 1/2 gallon thru both engines on that day. The planes sat for 6 days with the gas in the trailer. The first engine failed about 7 minutes into the first flight. The second about the same time into the second flight.

manofsteel

My Feedback: (2)

Joeairport is not quite getting the idea or really read what I said. I agreed to the fact that DA could have gotten a bad batch of rings....which THEY DID NOT MAKE. I have a DA50 for the past 3yrs and NEVER had a problem with it. I just feel that more can be done by any maufacture to help compensate the consumer. Give it rest. So don't criticize my workmanship. You know nothing of me.

JUGFLIER

O.K. UPDATE:

Desert Aircraft recieved both engines today. After they had time to disassemble the engines they called me about 6:00 pm Central time. After a discussion with the tech, I was told that they had no explanation for why two engines would fail with the same problem. He said that the engines were NOT carboned up, but that compared to engines that they usually service mine was VERY clean. There was no " jacking of the rings" meaning no carbon buildup behind the rings, he actually said the ring groove was as clean as they have seen. There was no sign of overheating and no scoring of the cylinder wall. The tech said they could have actually just stuck another ring into the engine and it would have been fine.

I leave you to make your own deductions on the cause but my belief if that they had some rings that were not properly heat treated that could not hold up to a load on a hot, high humidity day.
The tech went on to say that he had talked to the owner about the lost aircraft and he refused to do anything about the loss of a $700.00 aircraft that a 16 year old worked his butt off this summer to buy. I told them that i could repair most of the plane but if they would buy us a new fuselage for $209.00 i would be happy.... They refused. They did offer to give me a bottle or two of Red-line oil and to pay the shipping to me. Gee what a guy.

This brings ups to the next conclusion of this topic. With the new engines coming out today and their now established reliability, is it justifiable to spend twice the money on an engine that is not any better than an engine at half price? This is exactly the reason why we bought a DA in the first place. We wanted an engine that when yopu are torque rolling one foot off the ground won't lay down on you. This same engine has now due to the carburetor coming loose right after we got it and crashing a Great Planes Cap 232, cost us two aircraft at a cost of just over $1000.00.

I am done with Desert Aircraft, and even though i try to buy American, i will buy engines that i know people have had a good experience with. We are about to move into a 35% and in a year or two am making plans now to build a Carden or equivelent aircraft. You can bet that most likely it will not have a NEW DA on the front.

JUGFLIER

Pictures of the plane with the DA attached.

JUGFLIER

more

rcuman

WOW!!!
Evolution is out the door and now DA???
I guess there is Zenoah and Fuji left.
Or have I left one or two out?
I am sorry to hear about your engine failures but I think it may be a bit of bad luck.
Hopefully your luck will change.
Good Luck!!!

JUGFLIER

rcuman, You left out quite a few others. DL for one, I think they just came out with a twin for $799.00. It sure beats $1300.00 for a DA especially when they crash your plane.

rcuman

Jugflier:
This is exactly the reason why we bought a DA in the first place. We wanted an engine that when yopu are torque rolling one foot off the ground won't lay down on you. This same engine has now due to the carburetor coming loose right after we got it and crashing a Great Planes Cap 232, cost us two aircraft at a cost of just over $1000.00.


If I read correctly, you had this engine in another plane and crashed that plane due to the carburetor falling off and you put it in the current crashed plane and it had a faulty ring causing another crash.
Or was that a different DA engine?
Or did you just get the repaired DA back from the manufacture, popped it into another plane and crash that one too?
If it was a different DA engine could the problem have stemmed from you not tightening the carburetor securly to the engine?
I am just a little confused because you said earlier that you sent in two DAs that you were having problems with and the techs there found that they both had bad rings.
Not trying to start anything here but do you see my confusion?

JUGFLIER

RCUman
I see what you are saying. Let me clarify. I sent in two engines , 50 cc, and both of them had broken rings. They actually both broke on the same day, and both engines were bought about 2 or 3 months apart, but have pretty much the same runtime, and i mean down to minutes. One of the engines when it was new, only about a month, the carb bolts came loose and the engine died in harrier about 20 feet off the ground, the plane destroyed. We then bought a Nitro models yak 54 that it has been on about 7 months with most of the runtime the engine has on it, no problems. My sonn wanted to get the new H9 Carden yak and had worked this summer for the money. We put the plane together and put the SAME DA 50 on it. On the 5 th flight the ring broke and the plane crashed as you can tell by the pictures with heavy damage. One engine, bue to problems with it has cost us 2 planes @ $1000.00. Hope that helps.

Jake Ruddy

My Feedback: (40)

I have been quietly following this thread.. mainly because of all the stirring of the pot you did about your evolution.

I don't know of too many engine companies who are going to replace airframes because of an engine failure whether it be a dead stick, ignition failure, or a ring failure. Fact of the matter is there are 1000s of DA 50s out there alone let alone the 100s and 150s. I don't recall reading about many ring failures and I am surprised 2 broke in the same day from engines that weren't even in the same batch.


While I feel your pain, (I lost my first IMAC plane on the 6th flight this year because of a product failure) you can't expect people to start replacing airframes because of a failure like this... that's just unrealistic. Everytime your plane leaves the ground you accept the risk that something could go wrong.. that's just part of this hobby.

I encourage you to not turn this into a bashing DA thread because you didn't get what you wanted, all that will happen is the thread will get heavily moderated for bashing when I think there is some actual useful info within it.

rc-plane

Sorry for your loss but I dont think that you should give up on DA just because they would not replace your planes.

JUGFLIER

Thank you jake.
As you can see i learned my lesson from the past. As i said, based on the info given, people can make up their own minds. The two engines were purchsed only a month or two apart, so it is realistic that they could have been from the same production run.

In all states there are laws on product liability. If you had purchased an automobile, and the brakes failed resulting in the total loss of the car, The manufacturer would be legally reponsible for the liability resulting from the crash. I know if we are flying $99 arfs, that is one thing, it's not worth my time. But when you move to 50 cc or larger you are dealing with $700.00 airframes, $40 props, and other expensive items that are damaged or lost in a crash. If people are going to make a wise decision on what they buy, they need to know, that yes, even DAs fail.

blw

My Feedback: (3)

All engines are subject to quitting in flight for various reasons. Engines taken out of crashed models and put in other ones have a higher chance of problems if not checked thoroughly. That's a no brainer.

Let's move on past this......