daveopam

My Feedback: (9)

It acts a lot like a DLE20 I have on a profile. If it sits for a few weeks it does just like you said. I can see a bubble in the line that does not move. I use a three line set up in the tank. So I pull the plug on the fill line and blow in it while I hold my finger over the vent. (CAUTION: you will get a mouth full of gas if you pull your mouth of the fill line before you release pressure on the vent line.) With the ignition off I rock the prop back and forth with the pressure on. This will wet the carb. Once it starts it will start the rest of the day with no issues. I don't fly this plane enough to tinker with finding the source of the problem. When I have some time I am going to pull the reed block and fine sand the flat surface. If the choke butterfly has a hole I may try and block that off so the choke is stronger.
Sorry I can't be more help. These kinds of problems can really be frustrating.
David

Joystick TX

Everything left is outside the engine, muffler, fuel tank, fuel, prop, prop nut, etc. I can't wait to see what the root cause is.

Cub Flyer Fresno

Guess what! We tried that too! Only I blew on the vent line so I didn't get a mouth full of gas, just a mouth full of gas fumes. 🤣

You and me both bro! 😁

northwest

Hello gentlemen. I recently went through similar issues with two DLE20s and some rough running issues with an EME35.
My procedure now for a brand new engine is to disassemble the entire reed valve and block area, gently fine sand the mating surfaces, then use red hi temp silicone in a thin film on all mating surfaces and re-assemble. This is carefully done, including siliconing the bolt threads, just to be 100% sure there isn't an air leak in that area. Careful not to clog up any jets. Let sit for 12 hours before running.
It also seems like the smaller engines like to be well rich for that very first start, like 3 turns out on both needles for an easy first start. Once running for a few minutes the needles can be leaned to normal.
To make sure everything forward of the reed valve works we would inject gas into the plug hole onto the piston, screw in the plug and run the starter. If it fired the engine itself is good.
Could be some sort of air leak. Maybe try wetting suspected areas with soap water and dry run the starter to see if any bubbles appear.
You've tried almost everything else. Good luck.

northwest

Almost forgot to add...if it will prime but won't draw fuel with the choke open, try choking till wet then open the choke just a crack. The engine may continue to run with the choke slightly open like 1/4 open. While it is running try teasing the choke further open and play with the throttle and needles till it will draw fuel and run with choke open.
Hope this helps.

Joystick TX

I know you say it won't run, but that can mean a couple of things, like not at all, or for only a few seconds.

Will it run for a few seconds if you squirt a couple of drops directly into the carb air inlet to prime it?

Cub Flyer Fresno

Thanks for the tips, northwest! This "Almost forgot to add" one, we tried as well. I'll see if I can find any possible air leaks.

Joystick, to clarify, after choking until it tries to start (maybe a couple more flips for good measure), I'll open the choke. Then, after a couple flips, it will try to run for probably less than a second. Then, over the next two flips, it will still try to start, just a shorter duration until there's nothing. I can repeat that same procedure again and get the same result a second and third time, etc.. Does that make sense? I just got home from work so things are a little foggy upstairs. 🤪

Joystick TX

I'm not talking about using the choke at all, just squirting a few drops of fuel directly into the air inlet on the carb. It should run for a few seconds at least. If it will run that way, that eliminates a whole bunch of things that could be wrong.

northwest

This also a very good idea. Have the choke and throttle wife open, stand the airplane on its nose and drain fuel straight down into the carb. The fuel will drain past the reed valve directly into the engine body. If the engine and ignition is capable to run it will fire and at least burn off this fuel charge.
For now I strongly suspect a warped or leaky reed block. Could try either silicone sealing as suggested before or try the block from the other engine.

northwest

If willing to go through the trouble you could put the suspected reed block and carb on the ultimate engine and try a run, to isolate and eliminate.

Cub Flyer Fresno

I found this thread and I think it sounds a lot like mine. Maybe new gaskets would be in order?
https://www.rcgroups.com/forums/show...s-to-run-Fixed!

Joystick TX

Did you ever do these things?

The woodruff key may be sheared. You can check the timing with a good piston stop and degree wheel. Since you get a pop, that means you have fuel and spark, but maybe not at the right time.

If that is not the problem, it would be a good idea to pressure test the engine and looks for leaks.

Will it run for a few seconds if you squirt a couple of drops directly into the carb air inlet to prime it?

larry@coyotenet

My Feedback: (21)

Guys, after reading all the replies and giving a couple of ideas my self I think that, as Strother Martin said "What we have here is a failure to communicate". I spent 20 years doing computer troubleshooting and the most frustrating thing was to try to troubleshoot on the phone without being there. I am sure the problem will be solved when another modeler shows up in person and see exactly what is going on. Looking forward to finding out what was the culprit. There is an old computer tech story about the guy who called in that his computer was not working, after going through a list of questions the tech ask him what was on the screen. His answer was "wait a minute while I get a flashlight so that I can see the screen, we lost power here a while back!"
Larry

Cub Flyer Fresno

Hey guys! LOL She's still not running. Gave it a break for a while. Or I guess I should say I gave myself a break. So several modelers gave it a look out at the field. You know, we thought we had it there for a while. It ran for maybe 20 or 30 seconds, then quit. Couldn't get it started again. I said I was going to go through the fuel system again since that's what we tried out there. Never have. I got my 35% Extra 300 going again instead. That DLE 111 runs like a charm! Hmmm... NAH!!! Too big! But I digress. I'll get back to it sometime here. A 20CC plane is much easier to transport than a 111CC!

You have been updated!

daveopam

My Feedback: (9)

My 20cc is marginal on the profile I have it on. I'm looking at a 26cc from Valley View to cure my ills.

David

Cub Flyer Fresno

My DLE 20 is plenty for this Sbach, but after all this.... stuff... I've been going through, I'm actually considering throwing in the towel. Maybe I'll check that 26cc out.
No, wait... I have to try the fuel system stuff first. If it was that, there's no guarantee that the 26cc would work either.

Keep me posted on your profile and VVRC's 26cc engine. I want to hear how it works.

David

daveopam

My Feedback: (9)

I will post when the time comes. I'll probably do it over the winter. The 26 is a little wider and is going to require some nose surgery to mount.

David

Truckracer

My Feedback: (19)

The 20 is one damn fine little engine! There is nothing really different about it that separates it from other engines of similar size and construction. If you’re having problems with the 20 you could have the same problems with any one of several different engines. I’d suggest learning what the problem is and correct it in the 20. You’ll learn a lot in the process and be able to apply the knowledge to other engines in the future. Several of us here can talk you through a troubleshooting process if you’re willing to learn.

DGrant

My Feedback: (4)

Cub Flyer, Sorry I haven't been out at the field lately to check on that engine. Hopefully we'll catch up soon. I took a bit of a break after our long holiday weekend, and my staying at the field in my RV for those 4 days. That got me my fill of flying for a while. We've also been flying at Ave12,lately, mostly on the off days, and when it's a bit cooler. Although we're not flying giants out there, you know there's a really nice shade, and we've been flying it up with smaller sport planes, just hot-doggin it up... haha.

So don't give up on that engine..., I'm still curious about it, and I definitely haven't forgot.

hookedonrc

I must say that I am very disappointed after reading this thread. Just kidding.

I am having the same issues that you are with my DLE20 on a Top Flite Cessna 182. On the test bench at our field it ran great and so I moved on to the maiden flight. Shortly after take off, the engine would either idle or run full speed...nothing in between. When on idle, one click on the throttle and it was full speed, which made for an interesting flight to say the least. One of our club members tried to help by using the throttle trim while I tried just to keep the plane from turning into a kit. I got it down, but ended up snapping off the nose gear which punched through the sheeting right behind the firewall. Other damage was done as I set the plane down in tall grass (4') hoping to use it to cushion the landing. I will say even with the damage, the plane itself had little to no overall damage.

I then started to have the same problems you have. Terrible idle that is uneven, or it won't start at all, and no adjustment of the needle valve will help. With the choke closed, it draws fuel, but the first try to increase rpm's using the throttle and it dies. With the crash landing, I decided to send the engine in to Valley View RC and have them check it out. They did find a bad pick up on the ignition module and replace it. It then ran great in the shop and was returned to me. In the meantime, I re-engineered the throttle linkage, choke set up and checked the fuel system for a clog, and to make sure the fuel lines were all in place. No problems found and the engine was reinstalled after it was returned. So it then came time to restart after installation and I was excited to, finally, get my maiden in. Well, that never happened, and I am in the same situation as you are.

So, again, I worked on linkage to ensure it does not hit the pitts muffler during operation, and have tried twice to get it running, and no success. I set the needle valves at factory and finally got it to idle, but nothing worked. I will idle roughly (btw new gas/oil mixture) and finally quit on its own, or when trying to increase the rpm's with the throttle stick, it dies. So yesterday, I removed the tank again, and am going to move from a 3 line to a 2 line system. I am awaiting a new "gas" stopper, and tygon lines along with reducing the number of lines in the tank itself. The worst part of all this is that I have spent $86 on the repairs by Valley View..which ironically is more than a new ignition module, but they did get it running. Once I get the parts, I will again reinstall the tank, and try again.

I am like you, am on a quest to find the issue, but have, so far been unsuccessful. I will continue to update this thread in the hope that we both have the same problem.

ahicks

My Feedback: (2)

Did the spark plug boot contact the ground on that last "landing"? When you have one of those "arrivals", and it will not start afterward, most of the time the spark plug boot itself is the root of the evil. They're easily damaged! There's a silicone liner inside and if torn they will "leak" spark to the metal jacket. Not hard to change and not expensive.

hookedonrc

It is a good thought, but the ignition module was sent to Valley View along with the engine. They found the magnetic pickup to be bad and replaced it. I would think that the running problem would have been there if the cap was damaged. If the plumbing change in the tank doesn't work then I can focus on it.

Truckracer

My Feedback: (19)

Not necessarily on the cap! If damaged as Ahicks suggested, you might put it on one time and it would work. Another time it might not. My policy on caps is if they contact anything at any time, they get replaced. Even pushing on too far or crooked can damage the silicone insulator. Ahicks gave good advice! Read and heed! Has your cap ever contacted something that you know of?

ahicks

My Feedback: (2)

To make matters worse, very often the boot will check out fine when checked to see if it's firing the plug. The "gotcha" doesn't occur until the plug has been installed and it's trying to fire on the compression stroke - with much higher pressures involved. Believe it or not, those increased pressures make it harder for the plug to fire, often just enough harder where it's easier for the spark to make it to ground using the spark plug cap.

This is the issue that often as not makes a problem spark plug boot very difficult to diagnose - and one of the bigger reasons many flying a lot of gas will keep an extra ignition around.....

Thank God they rarely do this out of the blue. Only when you've had to pick dirt and pieces of gravel and grass out of them..... For the next few starts, keep this issue in mind! -Al

hookedonrc

Looks like I will be replacing it then. Exclamation points not withstanding.