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-   -   DLE 35 tuning question (http://www.rcuniverse.com/forum/gas-engines-142/11310514-dle-35-tuning-question.html)

600Bob 11-26-2012 09:31 PM

DLE 35 tuning question
 
So I have been breaking in my DLE 35RA and thought I had it tuned. I can go from idle to full throttle and it doesn't stumble or die. However if I run it at half throttle for a minute or so then go to full throttle it died like it was lean but since it only did from half to full and only after running for a time I wasn't sure which needle needed adjusting so I just fumbled around with it. Now I have it so it doesn't die but it does cut out briefly, sunden like, not bogging but then picks up and continues to run.

So do you think it is rich or lean, low needle or high needle. If I understand it correctly the low needle will effect the mixture over the whole throttle range but the high really only is at the top?

So how should I proceed to adjust it?<br type="_moz" />

ahicks 11-27-2012 06:56 AM

RE: DLE 35 tuning question
 
Trial and error? Note where you're at now so you can come back to it quickly/easily if/when you get lost. Then try a couple 1/8-1/4 turn changes to see what happens? Make them big changes so you can see their effect easily. Then as you get closer, make the adjustments smaller?

Regarding the low speed affecting the entire range, not going to argue that, but I will say it's going to be a relatively low percentage of the fuel being used above half throttle or so.

It may be a moot issue anyway. Keep in mind all you're trying to establish with ground tuning is something "close enough" that will allow you to get the plane in the air for final adjustment? Anything you're doing now is very likely to change before you're done. -Al

600Bob 11-27-2012 08:50 AM

RE: DLE 35 tuning question
 
Since it happens from 1/2 throttle to full would you adjust the high needle?  Plus it happens after running at 1/2 for a period of time, if I don't stay at 1/2 for long it will transition fine.<div>
</div><div>I have not noticed much if any difference going from ground to air with my gas engines.  And this engine sounded good on it's maiden except for that stutter after running at 1/2 throttle which it did in the air but it didn't die.</div>

acerc 11-27-2012 09:00 AM

RE: DLE 35 tuning question
 
600Bob is what your refering to as half throttle by the stick or the actual carb butterfly. They are seldom the same.

600Bob 11-27-2012 09:04 AM

RE: DLE 35 tuning question
 
Half throttle at the stick which is about 4300 or maybe 4500 RPM, full throttle, as I have it setup, is around 7700 RPM.

acerc 11-27-2012 09:10 AM

RE: DLE 35 tuning question
 
By those numbers half throttle should be around 3800 so I would start with checking the H needle. Then go back to the low and recheck.
The way I do that mid-ish range burble is get the motor good and warm, bring the throttle up until it is in the burble then adjust the(usually low) needle until almost gone.

MTK 11-27-2012 11:20 AM

RE: DLE 35 tuning question
 

Quote:

ORIGINAL: 600Bob

So I have been breaking in my DLE 35RA and thought I had it tuned. I can go from idle to full throttle and it doesn't stumble or die. However if I run it at half throttle for a minute or so then go to full throttle it died like it was lean but since it only did from half to full and only after running for a time I wasn't sure which needle needed adjusting so I just fumbled around with it. Now I have it so it doesn't die but it does cut out briefly, sunden like, not bogging but then picks up and continues to run.

So do you think it is rich or lean, low needle or high needle. If I understand it correctly the low needle will effect the mixture over the whole throttle range but the high really only is at the top?

So how should I proceed to adjust it?<br type="_moz" />
Bob,

I will have mine running in the next couple weeks too.

Based on what you describe, it sounds to melike your low end needle is a bit lean. Try 1/8 turn richer on LSN only. Another sure fire way to tell if the LSN is lean is as follows: from idle, jam throttle to full open. If it's lean it will die. How does it run at full throttle? Does it get hot and lose rpm or does it justsing along (albeit loudly) at steady speed?

600Bob 11-27-2012 11:30 AM

RE: DLE 35 tuning question
 
I have the top set for max RPM.  At one point it did slow down a bit so I enrichened it some as I recall.  It transitions from idle to full nicely, even from 1/2 to full is OK unless I let it run at 1/2 for a minute or so.  That is what got me confused, I had it so it seemed to run and transition real good then I just let it run at 1/2 for awhile then went to full throttle and it died like it was lean.  I guess I will go back to the HS needle then start over on the LS, I'm thinking it didn't burble much at mid throttle.  It's certainly much closer than it came out of the box, IIRC it was lean on top and rich on bottom.

3136 11-27-2012 01:25 PM

RE: DLE 35 tuning question
 
Hey Bob if it transitions well and you have it set for just slightly under peak rpm that should be fine.
Have you replaced the spark plug with a ngk?
How low rpm are you able to get it to idle without dieing?
Is it abnormally rough at idle?
what colour does the spark plug look like?

600Bob 11-27-2012 02:01 PM

RE: DLE 35 tuning question
 
DLE sparkplug, haven't had a reason to think it is bad so far.  When I had it out it didn't look fouled or lean, not enough time on it to really see much change.  I have had it down to about 1600 RPM but I woudn't trust it there yet but it didn't seem rough. I have tried to idle between 1800 and 1900 RPM.

3136 11-27-2012 04:42 PM

RE: DLE 35 tuning question
 
Hi Bob, the dle plug is known to be poor quality, they would be far better off not supplying a plug at all than their sub standard one.
Try a ngk or rcexel iridium plug.
Another question, does it start easily by flipping? if so the low needle should be ok, if it's hard to start by flipping it's most likely a little lean.

600Bob 11-27-2012 06:20 PM

RE: DLE 35 tuning question
 
I have had varying success hand flipping it, often it seems like it is kicking back but when I open the throttle more I have better luck.  When the weather permits I will see if fattening the low end helps.

bruceal 11-28-2012 06:35 AM

RE: DLE 35 tuning question
 
It sounds to me like the low is just a bit too rich.

WRK 11-28-2012 06:42 AM

RE: DLE 35 tuning question
 
Change the plug for a NGK before you do anything else!!

AWB Jr 02-15-2013 04:37 PM

RE: DLE 35 tuning question
 
My DLE 35 runs great at all ranges, The transition from WOT to idle is awesome. My issues comes when taxing, When about 1/4 throttle is applied, the engine sticks at that RPM about 2800-3000 and does not fall off until the throttle is "jockeyed"  to WOT and back to idle...
Makes taxing very difficult,,, I have tried riching the idle on the low end and still the same results. Is this something that in inherent with the DLE 35 or do I have a greater issue?

airraptor 02-15-2013 05:39 PM

RE: DLE 35 tuning question
 
anything binding in the throttle?

600Bob 02-16-2013 11:26 AM

RE: DLE 35 tuning question
 
What happen is you let it set for about 30 sec? The DLE 20 will run at a high idle for a long number of sec. before it drops to idle. I haven't noticed that with my DLE 35RA, or maybe it takes a few sec. before it settles but it's been a few months since I've run it so my memory isn't exact.

Quote:

ORIGINAL: AWB Jr

My DLE 35 runs great at all ranges, The transition from WOT to idle is awesome. My issues comes when taxing, When about 1/4 throttle is applied, the engine sticks at that RPM about 2800-3000 and does not fall off until the throttle is "jockeyed" to WOT and back to idle...
Makes taxing very difficult,,, I have triedriching the idle on the low end and still the same results. Is this something that in inherent with the DLE 35 or do I have a greater issue?

3136 02-16-2013 01:18 PM

RE: DLE 35 tuning question
 

Quote:

ORIGINAL: 600Bob

.............it seems like it is kicking back ................
After you put a ngk in it check the timing as well
http://www.rcextremepower.net/ignition_timing.html

I saw your vid in the other thread, nice plane!

MKnutson 02-17-2013 10:01 PM

RE: DLE 35 tuning question
 
I just picked up one of these engines the other day and while installing it found that the plug cap is a 90deg. and it won't work in between the pipes, it has to go around the side. Do the earlier versions have the 120 deg. cap? The 90 deg. cap hits the muffler.

Mark.

600Bob 02-18-2013 12:32 PM

RE: DLE 35 tuning question
 
I bought mine as soon as it was in stock, 90* cap, I run the lead around to the side.

MKnutson 02-20-2013 08:38 PM

RE: DLE 35 tuning question
 
I talked to the people I got the engine from, and they said it should have a 120 deg. cap on it. They sent me one no charge, very cool!
Thank You Valley Veiw R/C!!

Mark.


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