RC India

RC Equipments => Fuel and Engines => Topic started by: spitfire on February 09, 2011, 08:48:54 PM



Title: ASP 52 engine stops working when inverted
Post by: spitfire on February 09, 2011, 08:48:54 PM
I am facing a problem with ASP 52 glow engine.
Engine is working perfectly orientation of engine is normal. But when I invert the engine then it starts loosing power and stops within few moments.
I thought engine is not able to get fuel so I checked fuel tank setup and found that it is correct as similar setup is working perfectly with other engine.

Anybody knows what could be issue and how to resolve it...?


Title: Re: ASP 52 engine stops working when inverted
Post by: prateek13 on February 09, 2011, 09:44:51 PM
i dont know much about ic engines but what i can suggest is check all fuel lines


Title: Re: ASP 52 engine stops working when inverted
Post by: speedracer on February 09, 2011, 09:49:27 PM
I think a similar question was posted by Mr Anwar  it had something to do with the position of the muffler.....it got filled with oil when the engine was inverted....


Title: Re: ASP 52 engine stops working when inverted
Post by: deepikarun on February 09, 2011, 09:57:50 PM
I think you need to richen the main needle on the carb.


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 09, 2011, 10:17:28 PM
@ prateek13
I have replaced whole fuel tank setup and fuel lines with another one but the problem is still there.


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 09, 2011, 10:17:49 PM
@ speedracer
Could you please post the link to thread. BTW muffler is clean and doesnt get filled with oil when inverted.


Title: Re: ASP 52 engine stops working when inverted
Post by: flyingboxcar on February 09, 2011, 10:18:08 PM
Spitfire,
Can you provide more details on the setup?
What fuel you are using?
Is your engine run in or in the initial running in stage?
Is your High Speed needle peaked?
Is the engine mounted in the model?
Are you using standard supplied muffler?
What is the height of the tank in relation to the carb?
What kind of tank set up are you using?
Are you using pressure feed from muffler?
What plug are you using?
Can you hear the clunk go to the bottom of the tank when you turn the model upside down?(assuming the engine is on model)
All these would further help to troubleshoot for you  


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 09, 2011, 10:39:54 PM
@ flyingboxcar

Fuel used is 75% methanol and 25% castor.
engine is more than 6 months old and was working perfectly till now.
Needle is set at 1 turn.
Engine is mounted on model.
I am using muffler which was supplied with engine.
fuel tank is slightly below the carb.
I am using pressure feed from muffler.
I am using OS no 8 glow plug.
I haven't tried to hear the clunk go to the bottom of the tank when I turn the model upside down.I will do that tomorrow and let u know.


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 10, 2011, 10:02:20 PM
I checked for the cluck. It is going to bottom when inverted.
I set the needle at various positions from 0.8 to 1.8. The engine was running in normal orientation but when inverted it was stopping after a moment.

If anybody knows about such issue please help...!


Title: Re: ASP 52 engine stops working when inverted
Post by: divay99 on February 11, 2011, 12:01:31 AM
Ok so here is the solution
unscrew the end and then turn theback piece 90 degree....shouldbe good to go....



Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 11, 2011, 12:25:42 AM
divay

I will do this.
Will you please explain the reason to this....?


Title: Re: ASP 52 engine stops working when inverted
Post by: anwar on February 11, 2011, 02:33:39 AM
Does it quit even when you invert at mid throttle or above ?

 If it quits only on low throttle (or idle), then what Divay suggests makes sense, I have seen the same problem.  In any case, please let me know answer to the question above, and we can discuss further.


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 11, 2011, 12:33:18 PM
anwar

engine quits on low as well as mid and above.

I havent done what divay has told to do till now. should I do it or not...?


Title: Re: ASP 52 engine stops working when inverted
Post by: spitfire on February 11, 2011, 12:34:45 PM
Divay

Can you please explain how it will solve the problem..?


Title: Re: ASP 52 engine stops working when inverted
Post by: sushil_anand on February 11, 2011, 01:30:47 PM
Would like to know, too.


Title: Re: ASP 52 engine stops working when inverted
Post by: AEROVISHWA on February 11, 2011, 01:55:01 PM
spitfire,

i too had the same prob...
i guessed that the pressure vent in tank when inverted goes into the fuel......
creating bubbles..... might be these bubbles are caught in the inlet and your engine does not get a good supply of fuel..... leans out and cuts....

but this is not suppose to happen at low throttle... ???

does the clunk reach the bottom of the tank during invert...??


Title: Re: ASP 52 engine stops working when inverted
Post by: sushil_anand on February 11, 2011, 01:58:23 PM
In #8 he has said it does.


Title: Re: ASP 52 engine stops working when inverted
Post by: anwar on February 11, 2011, 02:26:26 PM
engine quits on low as well as mid and above.

At least once, we have experienced on our field where the exhaust was pointed upwards, and the engine would quit on low throttle.  I have a thread on this here, and I (and probably Divay too) was wondering if that is the case.  But at high at higher throttle ranges, this would not happen.  Probably a rich idle played a part in that.

Does not seem like the case you are experiencing.  In your case, you have to watch watch the fuel flow in the lines, and see what is happening.


Title: Re: ASP 52 engine stops working when inverted
Post by: divay99 on February 11, 2011, 08:01:04 PM
The mufler from inside has a deflection tray for the fuel to move out via the exhaust ... sometime during transportation, flight this tray comes loose( specially incase of asp engines) moving the exhaust pipe 90 degrees has known to solve the problem for two of my ASP engines. both asp .61a .....

Do try and let me know of the results... I am quite sure that this will solve your problem


Title: Re: ASP 52 engine stops working when inverted
Post by: flyingboxcar on February 24, 2011, 07:12:56 PM
Divay,
I have not used an ASP 61 but on my 52 and 90 the muffler has a circular exhaust baffle (basically it deadens the sharp two stroke noise) but there is no exhaust tray for the unburnt fuel to be chanelled out of exhaust outlet. Neither have I seen this feature in any engine till date. Would it be possible to post a picture of that feature?
From what you adviced, and as posted by Anwar on another thread I assume that if the muffler outlet is pointed up, the unburnt fuel starts to accumulate easily in the muffler body and during low throttle some of this can slosh back into the combustion chamber thereby leading to engine cut. But in such case, the cut should be abrupt and not as indicated above wherein it losses power slowly and dies out.
However the method suggested by you is an easy one to do and there is no harm in trying that out.

Considering that in upright condition the pressure feed into the tank will vent into the air space in the tank, and when inverted, it would start to do the same inside the fuel, it would lead to steady stream of bubbles in the tank. This could be one reason and would manifest in bubble in fuel feed as well. One way to check is to visually look for air bubbles when the model is inverted. If this is not possible, run the engine with muffler pressure line disconnected and then invert the model. if the engine behaves same i.e. cut outs as earlier then most probably it is due to bubbles in the line.
Would love to hear back from the original poster (Spitfire) whether he is able to solve his problem by using the two methods suggested above