DLE starting procedures

[Sam Longley]

I have a DLE20RA in an MX that I bought several years ago. The MX came with a YS but an experienced friend swopped it for a the DLE that I had used a few times before.

The plane has been successfully flown by 3 experienced fliers & trimmed out by my instructor, but I have held back flying it because I wanted to feel capable first. So it has lain unused since some time before the first lockdown

Today I decided it was time to fly it

The problem I have is that the engine fired - after a while. It ticked over of sorts, picked up after it warmed up then after 15 secs cut out. This happened several times & i followed the instructions & GENTLY adjusted the jets. After all it had run beautifully before so should not need too much adjustment.

In the end I gave up & bought it home, took off the cowling, placed it in a well tied down stand & tried again. I cleaned the plug first.

The fuel is 1:30 mixed about 3 months ago.

I set the jets to factory settings & was surprised that in lieu of the suggested one turn out, they both seemed to be more like 2.5 turns.!!!

The engine started after the suggested choke cycle. I have no problem getting it to fire up & give a few seconds or more running, sometimes a minute.

However, different starts produce different revs even though I might not have changed the slow running needle or throttle. ie sometimes it runs fast, sometimes slow. When I adjust slow running to get an even run then accelerate I sometimes get high revs for 15 secs then it cuts out. Opening the needle even quite a lot does not seem to make any difference

I know that the engine has run very well, so I suspect that it is the way that I am going about setting it up from the beginning. (The servos are set properly with good linkages)

Can someone who really understands these engines be good enough to run through how I should go through the CORRECT, FULL procedure please. The instructions are a little vague

It would be most apreciated

Thanks

from a frustrated

Sam Longley

 

[Martin Harris - Moderator]

The pump diaphragm may have gone hard, especially if it was stored dry.  In the absence of any informed opinion/advice, I'd suggest it may need changing.

[Denis Watkins]

You beat me to it, engine was ok over a year ago, dry diaphragm, and cassandras comment

[Don Fry]

Nowadays, given petrol has ethanol in it, the instructions for my outboards say, use within a month. If left in the carb it leaves a horrible slimy rubbery grunge. The motor does not run, runs like a three legged hare, until it’s cleaned out.

For that reason, I use the stuff from the farm/ garden centre (Alkylat in France, but it the sameish name in the UK) for aircraft engines, and make sure the outboards are running on it when put to store. Given the symptoms I would prefer the diaphragm theory, but given the age of your fuel it’s a contender. 

 

 

[Frank Skilbeck]

Don, the brand name over here for synthetic petrol is Aspen, available from garden machinery stores.

[Martin Harris - Moderator]

It may be that your oil has stabilisers in it.  I buy premium grade for model/implement use as it has less or (increasingly rarely) no ethanol content.

[J D 8]

   A fellow club member has the same problem with the same engine and has struggled with it for a while now, one week it runs fine then then in a couple weeks same symptoms as yours. All of Cassandra's suggestions done with no improvement.

Trying to help I did some reading up on Walbro carbs and agree with Martin above about changing the diaphragm and also the needle flow valve.[ the tip of the needle has a nitrile rubber coating that can go sticky over time  However it recommended getting an original Walbro overhaul kit, Chinese carb [ a walbro copy] rubber parts not so good.   None of the above has happened yet.

[Don Fry]

1 hour ago, Cassandra said:

I am currently using petrol that must be a least 18 months old E5 (5% ethanol) in a DLE 30 with no issues starting and running.

Happy days then. I’m only quoting what Mariner/Mercury engines say in the instructions. And relating what I scrape out of carbs, not mine may I add. I also recall that motor manufacturers have never been keen on old two stoke fuel. 
My boat has two motors on board, if one does not want to play, change motor, or if desperate, hitch a tow. 
Try those tricks 50 meters up. Old fuel is a failure point. For a couple of quid.
 

[Don Fry]

1 hour ago, Frank Skilbeck said:

Don, the brand name over here for synthetic petrol is Aspen, available from garden machinery stores.

That’s it, thank you Denis

[Don Fry]

I reiterate, I have read the manual for my motor.  It says use within a month. 
For information E5 is available here.
Phase separation is marketing speak for getting watery chewing gum out of carbs. 

I know Aspen is disgusting. It comes out of a petroleum cracking plant, same as petrol does.

[Sam Longley]

I am watching the comments with interest & I thank those posting for their attention.

I have a couple of points.

1) I used a 2 stroke oil from a garden centre presumably as used in a strimmer

Would users like to recommend a make of 2 stroke oil easily obtainable in the UK that would be better. I wonder if that might be an issue.I have no clue about additives etc.

I have to say that I am not convinced about degradation of the petrol itself, but I will change it & start all over again if that is going to solve the issues.

 

2) I can understand the diaphragm issue & would like to purchase a service kit. I saw the comment about cloned parts & wish to avoid this. Can anyone suggest a reliable UK source for the stockists of parts for DLE engines. My local shop would not stock such an item due to low demand so I need to find the UK supplier who can supply by return.

 

3) Finally, no one has yet explained the starting procedure accompanied with jet adjustment within this. I assume that most just assume that I should know. Perhaps I should & that is seriously remiss of me. However, getting it confirmed from someone who actually knows would really help

 

I am sure that I am not the only one who might benefit from this info

Or perhaps it really is just me !!!!!!!

Sam Longley

Edited June 10, 2021 by Sam Longley
word correction

[Kim Taylor]

Hi Sam

I hope I'll be forgiven for posting a link to another forum, but I've found this helpful: https://www.flyinggiants.com/forums/showthread.php?t=427#post3925

Theres also this: https://www.flyinggiants.com/forums/showthread.php?t=194009

As you will see from the length of the threads, if you ask 20 modellers how to tune a motor, you'll get 25 opinions, but you should get a starting point. I think the 'book' starting point is 1 1/2 turns open on both high and low, then tune as necessary when running, but have a look and see.

Hope that helps

Kim

 

[J D 8]

   The carb fitted to DLE 20 is a clone of the Walbro WT793  Overhaul kit is K-10 and K-20 [ more bits ] You won't need all the bits in the kits.   I have no petrol aircraft engines myself but the carbs are very common on strimmers / bushwhackers ect.    For parts try JAPG mowers and machinery Hereford. Tel 01432 381193.

[GrumpyGnome]

@Sam Longleythe petrol experts in my club all use the oil available from DeLuxe materials - certainly not cheap!

 

This is how my mate helped tune my petrol engine.

 

1) set needles per the manual - for me this was 1 1/4 out low speed needle (lsn); 1 3/4 out high needle (hsn).  May of course be different for your engine

2) Choke on, 50% throttle, spin it over until it 'pops' a few times

3) Choke in, about 20% throttle, spin it over, and let it warm up on about 25% throttle for about a minute 

4) Adjust hsn for max revs

5) Let it idle for about 10 seconds, increase throttle quite quickly. Good pickup - job done! Seems to bog down - lsn is too lean - tiny adjustments. Repeat. If it splutters - lsn is too rich - tiny adjustment

6) Try full throttle for max revs.  Small adjustment may be needed. Repeat steps 4) to 6) until you get full revs and a clean pickup).

 

Once this was done, holding the model at any attitude seemed to have no detrimental effect.

 

Worked for my engine. 

 

You may well get a few other methods to try ?

 

GG

 

[Martin McIntosh]

I had the same problem with an RCG 30 which uses a Walbro copy. Obviously a hardened diaphragm and a call to Morris Mini Motors got me a DLE overhaul kit which cured it. The last thing you should have done was to start fiddling with adjustments considering that the motor was previously running OK. These carbs are in all sorts of garden tools and you don`t go adjusting them every time they come out of the shed, do you?

In my experience old petroil is fine to use. You can download a comprehensive guide on setting up a Walbro from scratch. Changing either jet setting means that the other will also need adjustment to compensate.

[Don Fry]

In fairness, Martin, the average petrol tool out of the factory, is tuned by a young person, who does 4 a minute. That’s piece work. Not exact. They run.
Grumpy Gnome, has given a set of good instructions to recover the settings. One observation, when you close the needles, close, carefully, don’t bend the ends. 

I earned 300 euro today sorting oil petrol water problems.  ( outboards for boats), 200 tomorrow. Thereafter, work shop is closed, I’m off on holiday for the Summer. And I don’t work, I’m retired. Favours to acquaintances. 

But, lose the settings of a petrol motor is no different from a glow motor. Top end, bottom end, back to top, back to……until it’s runs correctly.

 

one provocative view, why do we mess with these petrol motors. Glow motors are simply easier technology at this size. Go fly. Full stop. But then we do fuel proofer. 
 

A glow motor, prepared for storage will be good when recovered. Where I live, the woodcutters chuck their chainsaws out when knackered. Two years old? We do not do the hours in the air to approach that. Our poster is disappointed, his petrol motor does not run without a repair kit after a layoff. That is the nature of the carb, it needs to run.

[GrumpyGnome]

Main reason I got one is cost.  A gallon of glow is around £25 and will last me around 4 flying sessions.  A gallon of petrol is far far cheaper and will last me at least 10.... purchase cost now seems on a par(ish), and 2 stroke petrol power is pretty similar to four stroke glow.

 

Second reason is mess - planes, hands just get a quick wife with nappy wipes.

 

The noise is horrid of course but I am lucky that we are very rural and have no noise restrictions.

 

In an ideal world, I'd like four stroke petrol but that is currently cost prohibitive, and I expect power to weight is less than ideal. 

 

I do still love my Saito though....... needs no fiddling ever but I guess it's higher quality than my cheap petrol engines.

 

Re carb drying out, I store them with some fuel in the tank and turn them over every week just to keep them 'wet'.

 

Variety is the spice of life ! (paraphrased)

 

GG

 

Ops, I seem to be going a little off topic - apologies.

Edited June 11, 2021 by GrumpyGnome
Apology for off topic......

[GrumpyGnome]

39 minutes ago, Cassandra said:

 

There are things called silencers (some people call them mufflers) that you can buy for engines. You bolt them to the exhaust port in place of the bit of scrap metal that comes with the engine. They make a huge difference to the noise that the engine makes.

 

 

?

 

? Lol.

 

Cheap canisters look nice but seem to do little to the actual sound - maybe a slight reduction in 'bark'.  Expensive, multi-chamber systems seem far better, but even then my naked ear tells me they are still loud...... 

 

Third party pitts style or wrap around mufflers seem to have no effect on volume.  

 

(this is all subjective as I have not walked around taking dB readings!)

 

Hopefully, if petrol popularity continues to increase, we will have more choices. 

[Sam Longley]

On 10/06/2021 at 14:16, Kim Taylor said:

Hi Sam

I hope I'll be forgiven for posting a link to another forum, but I've found this helpful: https://www.flyinggiants.com/forums/showthread.php?t=427#post3925

Theres also this: https://www.flyinggiants.com/forums/showthread.php?t=194009

As you will see from the length of the threads, if you ask 20 modellers how to tune a motor, you'll get 25 opinions, but you should get a starting point. I think the 'book' starting point is 1 1/2 turns open on both high and low, then tune as necessary when running, but have a look and see.

Hope that helps

Kim

 

Cheers . That first link is a great help. Very detailed. I have printed it out & will take it to the field & study it when I next get to play with it.

So thanks again

Sam L

[Engine Doctor]

Starting if everything is working OK is simple.

Make sure fuel is in carb. I do this by simply blocking the carbon with a finger and turn engine over until fuel is seen entering carb ( if you have transparent tubing) or until you feel petrol in the carb on your fingers.

Put choke on and switch on ignition. 

Flick engine and it should pop a couple of times and stop.

Turn choke off and flick again and engine should start after a few flicks. Allow to warm up for a short while and engine should now run and pick up easily. 

If it cuts out when you try to open throttle , repeat choke procedure.

If it won't start and you can smell petrol from the exhaust it's flooded. For a flooded engine try removing g plug and spinning over with wide open throttle.; FIRST MAKING SURE THE IGNITION IS SWITCHED OFF.

Refit plug close throttle and start. 

A well set up petrol two stroke will always start easily provide it has a working carb (good diaphragm), good fuel, good primary and seccondary compression and a good spark.

 

[GrumpyGnome]

I didn't say that a DECENT canister makes no discernible difference ...... it clearly does but 2 stroke petrol engines remain loud. I don't need a dB meter to tell that.

 

Although there are lots of alternatives, effective ones are quite expensive and it seems a shame that having spent a few/several hundred pounds on an engine, you then need to throw away part of it and spend another 100 pounds plus.  Hopefully increased popularity will bring greater choice.

[Frank Skilbeck]

1 minute ago, Cassandra said:

 

The choice of third party silencers for petrol engines looks to be more or less the same today as it was 10 or so years ago when I setup my first petrol engined model. 

 

Probably because the largest market or these engines isn't so noise sensitive as the UK.

 

We have a couple of 30-50cc petrol models in our club that have met the 82dBA @ 7m limit with good quality aftermarket cans, but these were not cheap. 

[Ron Gray]

There is a saying that when buying a 2 stroke gasser be prepared to spend the same amount again on a decent silencing system! Whilst I have several DLEs and they are all equipped with decent cans, I tend not to fly them as much as I used to as I prefer the sound of 4 strokes, especially Lasers!

[Sam Longley]

As an upate to my earlier posts. i found an experienced club member who could not tune the engine after a few minutes. His suggestion was that the 2 stroke oil had gummed the works after a 2 year lay up and the filter was possibly clogged. I have since removed the cover & he was right about the filter so I have blown through with carb cleaner. He felt that fact that it started easily, but ran poorly, pointed to the diaphragm being Ok but as a service kit is so cheap there would be no harm in changing.

He put me onto a contact & I rang - Gas Guzzler on 01536 510136 ( am I allowed to state companies on the forum?)- Their web site show lots of DLE parts but not all. The phone call put me on to a chap called Paul who immediately knew what I wanted. He has sold me the carb service kit, some 2 stroke formulated for models & a new NGK spark plug .

I expect to receive all this tomorrow. I will report further when I have installed & changed the fuel

Edited June 14, 2021 by Sam Longley
altered text

[Engine Doctor]

Yes , the diaphragm can go hard . Just serviced the club Strimmer and found the diaphragm had gone hard. If the middle part was moved it clicked  like piece of plastic !

As you say , service kits are so cheap just do the service anyway. From September ( I think)  our petrol will be changed from E5 to E10 meaning 10% ethanol and this will cause more problems with pumped carbs after any lay up. Also expect to see an increase of engine bearing failure due to rust caused by water absorption in the fuel.

E5 fuel is bad enough but E10 will cause more corrosion and agro .

Edited June 15, 2021 by Engine Doctor