RC India

pls review on ASP engines..

I know a few people using ASP and have heard very good reviews.  ASPs are OS clones and you can interchange parts between similar sized engines.  Atleast thats what I heard.  I even know of an ASP engine running with OS parts!!

- Chan

i know nothing about glow gas or nitro (hopefully will in future).
just trying to help. googled on ASP and found something that might be useful.
http://www.justengines.unseen.org/acatalog-cgi/ss000001.pl?page=search&PR=-1&TB=A&SS=ASP&ACTION=quick+search (http://www.justengines.unseen.org/acatalog-cgi/ss000001.pl?page=search&PR=-1&TB=A&SS=ASP&ACTION=quick+search)
sorry if that doesnot help as am into electric (less noise less pollution ;D ;D ;D) (and of course less global warming  ;D ;D) (glow gas or nitro lovers please take it lightly  8-) 8-) 8-) 8-))

I have an ASP 46 and runs very well, they are indentical to the SC engines of which I have a 15 year old SC61 and SC40 both of which I retired after 11 years. They are available from Just Engines in UK who provide a very good service, after I ploughed my spitfire into a tarmac runway, I sent the engine (what was left of it) back to them and they fixed it in a very short time.. still running.  Personally I wouldn't even look at anything else!!

I never owned one, but had the chance to work on them a few times at the field.  I felt they are little harder to tune (ie, getting the low and high speed needles correctly set) as compared to OS. 

Once set, they are very smooth.

i am using ASP engines but not satisfied with RPM  always problem

might be i received this the only one hard difficult piece by chance
but in this price i would like to try once again

Dear pikle, Why take lightly? Everyone who pollutes this planet is responsible. there should be a complete ban on glow/gas engine or atleast some emission control.  we should not allow anymore pollution just because its cheaper.

Crazypilot...

What a thought.. .Simply "WoW" ;)

Yes similarly all the factories manufactring batteries,motors and ESC should be shut, complete ban on felling of Balsa trees, ban on all factories producing any kind of foam as they are all non biodegradable. That would make sure there is no pollution 

Yes, actually I have experience of the reverse. I have an OS 46 FX running on ASP parts as OS stopped supporting these engines. There should be no reason why exactly the reverse should not be possible
SC, Magnum, ASP are all manufactured at the same factory and ASP's main business is manufacturing full size Turbines.
I have used ASP 2T (mixed reaction), and 4T. The engines are exact copy of older OS engines and hence when compared to newer OS engines are less powerful. But then if you are looking for power, OS is not the leader anyway.
The ASP's are easy to tune run satisfactorily, the only area where these engines suffer is probably the QC.

  

I have been using ASP61 2 Stroke (remote needle) on my SPAD for the last 1 year. NO problems at all. Initial tuning is a bit harder (as rightly quoted by Anwar) but once set, they perform really well.

I was using it on my Extra 330L (CmPro) initially but had problems heating up the engine. For some reasons, the engine did not like the cowl and used to die quite often during flights (airflow through the cowl was quite reasonable.) But once I put it on my SPAD, it has been behaving really well. It is open now. No cowl. APC 13*4 prop. No deadsticks AT ALL...  ;D

initial tunning is only problem! mine is ASP28 from RCD running on trainer ,after year (60 flights) still flying ! starts on single flip

Every one is not an Aeroplane mechanic  >:D

Just kidding.  ;)

 ha ha ha
 ;D ;D ;D
vinay but i have worked on only one piston engined aircraft that too during training,
dh104
we used to call "daadi maa"

LOL!  ;D

I was initially skeptical of ASP. But my ASP 91 on my YAK 54 changed my view 180deg. Yes slightly tricky on initial tuning, but once that is in place I find it to perform better them OS. Superb power, no more engine cuts. I was recommended not to use nitro on these but I am using 5% nitro & it's firing really well. Just received my ASP 108 & ASP 52, can't wait to fier them. Excellent buy for the price. I would rate it 4/5.

Saurabh,
It is not the cowl or the engine which was creating problem. You need to ensure that air actually flows past all around the engine.
Most of the time what is noticed is that people cut up the front and rear and assume the engine would receive sufficient cooling, you need to force the air through the desired route and baffling comes in real useful in cowled engine.
If you have ever come across CL speed models you would immediately realise what I am saying. You would not beleive if you see the inlet and outlet for air, and these engines run at WOT all the time and pump out all the power.

For example see here : Google Link (http://www.google.co.in/imgres?imgurl=http://dkd.net/clmodels/art/comhiern.jpg&imgrefurl=http://dkd.net/clmodels/hiern.html&usg=__U_QtoytzK95_owslBvBnf6LYqk0=&h=639&w=285&sz=54&hl=en&start=5&zoom=1&um=1&itbs=1&tbnid=4oHwj-4atW9IeM:&tbnh=137&tbnw=61&prev=/images%3Fq%3Dcontrol%2Bline%2Bspeed%2Bmodels%26um%3D1%26hl%3Den%26sa%3DN%26ndsp%3D20%26biw%3D1252%26bih%3D830%26tbs%3Disch:1)

Or see these pictures, you can see how tightly the engine is cowled and the size of air inlet and exit. Now comapre this to the usual size of openings you see on an average RC airplane  :giggle:
  

Hi.
Thanks for the pic and the link.

I do agree that you need to push the air into the cowl and to the right spots. Maybe that was the problem...
but now since the engine is out and performing well, i guess I am OK.

however going forward, will take care of it.

Thanks for your time and appreciate your inputs.

We (Mike, myself, and another old timer aeromodeller hailing from Delhi named Mr Shrivatsava) had a heck of a time today with an old 40 size ASP engine owned by Mr.Shrivastava. 

Here are the symptoms / obeservations :

1.  Basically, if we kept the engine in idle, the engine would gradually run slower and slower and quit.

2.  If we gradually increased the throttle and kept it above about 25%, it would not die at all.  If we applied throttle suddenly after a few seconds in idle, the engine would quit immediately.

3.  The transition from low to high was a bit hesitant. 

4.  The best performance on the high needle was around 0.8 turns (NOTE... less than 1 turn !).

5.  It had a remote needle, and some very small bubbles were forming in the fuel tube connecting the remote needle to the carb.  Mike, who hated remote needles like anything ;) , wanted to remove it from the equation.  But he left before our investigation was complete, and we detected a small crack in that piece of fuel tube.  That took care of the bubbles, but did not fix the "quitting on idle or sudden throttle" issue.

6.  No amount of "sensible" (you will know why I used this word... in a minute) tuning would fix the idle.

7.  Fuel was good, glow plug was new.

8.  Finally, we opened up the carb and cleaned it.  While at it, we decided to make Mike happy, so we moved the high needle from the remote to the carb itself.  After all of this, still the idle problem persisted.

9.  Finally, I decided to try something unsensible, we closed the low needle all the way, and started the engine.  The reason for this is that making it rich was not helping (not hurting much either), so I went the other way, leaning it out bit by bit.  To our surprise, the idle was perfect, the transitions were great, and the backplate was barely warm to touch even after running for couple of minutes in idle like this ! 

So at the low needle fully closed, and high needle at 0.75 turns open, we had what looked like a well tuned engine.  We flew couple of sorties like that before calling it a day. 

My question is, can anyone explain why the idle needed had to be closed (or just about closed) for the idle to be smooth ? 

And is it normal for ASP engines to have the main/high needle only 0.75 turns open for best performance (as compared to OS engines where the sweetspot is between 1 and 1.5 turns) ?

was the fuel - no nitro ? and castor oil ?

10% nitro, I believe it was Byron brand.

The other question this brings up is what should one's understanding be when you quickly pump throttle and the engine quits.  I remember Sushil bhai commenting earlier that it is an indication of being too lean, and in that case, it was proved true.  In this case, it turned out that it was an issue with the needle setting being too rich.  Too much fuel drowns out the plug, and this is compounded if the plug is already weak.

My understanding is that you have to closely watch for HOW it dies. If it throws out a lot of fuel and then dies, it is too rich, if not it is too lean.  Looking for comments on this too...

Exactly! If it dies immediately on opening the throttle the idle setting is probably too lean. If rich, it will splutter and then die.

Do note that the idle settings - in most engines - are fairly sensitive. Try about 1/8th turn at a time.

Yes, we went very very slow on the small needle, we always do 10 to 15 degrees at a time. 

And regarding the splutter, it did not ! Death was near instant, we could barely detect a huge gush of fuel/fumes, yet it was later diagnosed to be too rich. This is one reason why we tried going both ways, as it had become difficult to detect the required changes just by observing symptoms alone.



       

In my experience,

1.) ASP engines need very less opening of the throttle at idling (as compared to OS)
2.) My ASP60 is perfectly tuned to deliver max performance at high speed tuned at 0.70 - 0.75 turns. (Whereas OS has a sweetspot at 1.25 approx) Very rightly pointed by Anwar.
3.) As I was reading through Anwar's post, I could visualize the situation and could immediately make out that the engine might be running too rich rather than lean. ASP engines may not sputter if they are running too rich (Instant pumping will cause a sudden gush of fuel (may not be noticable) into the chamber causing it to die almost instantly. Also, at times the sputter is so small that it is hardly noticable/detectable.
4.) The reason for dying after a few seconds at idling is also very common when the engine is running rich, as the excess fuel keeps building in the chamber and the crankcase which eventually causes the engine to die.

In such situations, where it becomes difficult to assertain the reason for unreliable idling/performance, it is best to close the high end completely and start from scratch. It is best to open the needle by just 1 turn and then start making adjustments from there. Incase of OS, it will be quite apparent that the engine would be struggling at full throttle at this tuning, hence suggesting to open the needle a bit more.
On ASP, it will become apparent by looking at the exhaust fumes (excess smoke) indicating that the engine is running rich.

Only once the high end is tuned for optimum performance, should you adjust the low end for a smoother idling and acceleration.

Glad you got it sorted!

Does this mean we can raise ASP status to

Always Settup Properly!!

I will look out the procedure to obtain the inital settings on low needle set up by blowing through the fuel pipe, which is what I tried to do at the field but as you say, you really have to close it down completely and work your way up.

From what I have read everyone is on the right track but the "sweet spot" can be hard to find, if you remember we had the same issues on my Moki 135 earlier this year.

 

Anwar,
As others have said these are classic symptoms of the low end being rich. Fuel builds up while idleing and eventually the engine will quit as the plug loses heat or it will quit the moment you try and increase throttle (with the extra fuel which puts the fire out as it were). 
An easy test for checking if the low end is rich is to pinch the fuel line at idle  -the engine should just speed up - if you have to really pinch down on the fuel line before the rpm changes - its too rich. (And of-course if the engine quits its too lean)

I own a ASP 52 and its a great engine - been running it for the past 6-7 yrs in many diff airplanes - very powerful for its size and will swing a 12x6 prop with authority. I also had the initial tuning problems when running it in. 

I forgot to mention the pinch test.  Everything indicated that we are too rich.  Mike did his "blow test" also, to confirm that the low end is rich.  But what we were surprised about, and why I posted this here is to get confirmation that with ASP engines, the low needle needs very little opening (at least in some cases), and the high can be as low as 0.7 turns !  These would be considered very bad settings for other engines.  Saurabh's post provided the confirmation I was looking for. 

It is not that we did not identify the symptoms, it was the fact that the solution was so extreme that surprised us :o

This also shows that when it comes to tuning, there are no hard and fast rules.  Whatever works without overheating the engine, shall be acceptable.

well, I was just going by the implications of these two statements. The reason I said that these were classic symptoms of a rich low end was your first description of the engine slowing down and dying (as opposed to just quitting) after idling for some time. This tells me that the engine is loading up. (although of course hindsight is 20/20 :) )
When I was learning to fly I was always told "clear the throat" of the engine just before takeoff (i.e. run it at mid to full throttle) after a prolonged idle -such as taxiing to the flight line from the pitts. This was even if one had run it at full throttle and done the tilt test in the pitts -of lifting the nose up check if engine is too lean and quits at full throttle).   

True, the classic symptoms were recognized too. But the point is that even by starting at one turn from fully closed on the LSN caused the same symptoms, so we were going richer for the fear of killing the engine (driven more by fear/common knowledge... than just the symptoms). Who would try an engine with the LSN pretty much fully closed ?  And there was virtually no difference in behavior for up to 3 turns (we stopped playing with "rich" settings at that point). Something as sensitive as the low needle should induce some difference in behavior (one would expect!), but NONE !!!  No change in the time required for the engine to die in idle, no change in the way it stopped on sudden high throttle, etc ! 

Looks like ASP just lived up to it name again of being funky at tuning.

Look at the the total picture:

You use electricity to charge your battery. Electricity production/generation causes pollution & warming

You use LiPo or NiMh, their production causes the same, and their disposal is a major pollution hazard

Best to train a bird!