kenh3497

I've been very lucky to acquire a new to me pattern ship. It's an older design Smargard and it is not pristine by any means but seems pretty solid. It comes equipped with JR 4721's aileron elevator Small JR for throttle Futaba 9606 rudder. Dz 140 on a soft mount with spinner and prop. Exhaust system header and Hatroi pipe.Bolly carbon fiber landing gear Bolly carbon fiber wing tube.

The only downer is the header is not usable. The flange inside the header that is captured by the "nut" has disappeared due to use and I assume being run loose from time to time. The only fix I can see is a replacement header. It will be a bit before I can add a new header to my budget though. In the mean time I will get the rest of the air frame ready to fly. Shouldn't take much.

Ken

Ken

speedracerntrixie

My Feedback: (29)

Ken congratulations on your new purchase. I had gotten my last two headers off eBay as they were flex headers that were only about 45.00. I looked but they no longer seem to be listed but may be worth checking every couple of days. There may be somone here that will step up with a spare.

You had asked about my experiences on the 140 DZ on RCG but I am going to relate my experiences here so that others can add their findings as well.

With both my YS 4 strokes I use only OS F plugs and I run them on 30% nitro 21% synthetic oil. Fuel packaged for heli use using a lower viscosity oil has worked the best. The 140 leaves a very good smoke trail do not mistake this for running rich. Listen to the engine to tune and just know it leaves a good smoke trail. Also highly reccomended is the YS in tank filter clunk.

Now the fun stuff. Start out with the regulator screw flush with the housing. If the engine was set up well from the previous owner and you intend to not take anything apart then leave his setting and go from there. The more in the screw is adjusted the more fuel pressure the carb gets. Mine has to be adjusted about .5 mm in. I'm not sure if this charictaristic is for all DZ 140 engines or just mine but by adjusting the pump pressure up I had issues with the line that runs from the pump to the carb. First the line would pop off, then once secured to the fitting the line would split. I eventually found an eBay source for nylon high pressure 2.7mm ID tube and have had no issues since. The reason for having to adjust the pressure on my particular engine was that I had a lean spot at just below 1/4 throttle that could only be fixed by increasing pump pressure. The high speed needle seems to affect only full throttle. Start at 2.5 turns out and transition to full throttle slowly. Any sign of detonation during transition bring back to idle, shut down and increase pump pressure. Once a smooth transition is accomplished once you get to full throttle and the high speed needle takes over at 2.5 turns out you will undoubtedly hear a drop off in RPM. Lean the high speed needle just to the point where no drop off is noticed.

starting process. After each outting I run my engines dry. This burns off the nitro and methanol but leaves enough oil behind to protect. The pump and lines will be dry. I go to full throttle without glow and turn the engine over by hand 10-15 times to get the pump wet and to get fuel into the high pressure line. Bring to idle hook up glow and it usually only takes a bump with the starter. All runs after that I hand flip the prop 3 times and then bump with the starter. Once running let it run at high idle for 10-15 seconds to make sure all air in the lines has been purged. I'm adding a couple pictures. The one of the engine shows the high pressure line that is the clear tube and not the pink. The in flight picture shows the smoke trail common with this engine. Feel free to ask questions, if I don't have an answer I have Verano's cell number and use it frequently. If anyone else has tidbits to add please feel free to do so.

flywilly

My Feedback: (121)

http://www.rcgroups.com/forums/showthread.php?t=2735249
Here's a header that should work.
Nice airplane. A Wolfgang Matt design; so it should fly well!

kenh3497

Thanks guys! I found a thread here on RCU in which Troy Newman explained the ins and outs of the DZ 140. Of course I didn't bookmark the page so now i have to go back and find it. I know a lot of this may and is old hat to quite a few but for some including myself it is still new territory.

This 140 is a bit on the tired side. I pulled the backplate today and it will need a new con rod very soon. The valves were right in spec and the PO said it was a "good" engine. This winter I'll pull it apart and see what it needs. I received a SUPER deal on the plane. I have room to spend some cash on repairs. I just need the cash to spend. The PO said to call, email etc any time. He wants more pattern pilots in Iowa and is willing to do a little extra to help out.

I'll take a look at the flex header and decide if it might work. The PO is checking with his pattern buddies to see if one of them might have something laying around. You think there would be hundreds of headers laying around as glow powered pattern seems to be on the wain.

Ken

flywilly

My Feedback: (121)

Hi Ken,
Yes, glow powered pattern is, sadly, becoming a dinosaur. There are only a small number of pilots still flying glow, but Bryan Hebert and Brett Wickheiser are trying to keep the 'flame' alive (or the plug ignited). There should be a lot of relatively recent engines and parts available, but if the owners have gone exclusively electric they may not even read this forum. There was pretty good response the the other YS thread here with engines available.
Good Luck!

kenh3497

HMMMM... Maybe I should post in the electric forum????? I think I will!! Thanks flywilly, for the tip!

Ken

kenh3497

Finally found the post by Troy Newman here;
http://www.rcuniverse.com/forum/ys-e...ml#post5445231

The complete thread is here;
http://www.rcuniverse.com/forum/ys-e...dz-tuning.html

Like I said before to many this is old hat, but for me it is a wealth of info. Thanks Shawn for posting your experience with the 140 DZ. Everything helps!

Ken

apereira

If you think is worn, and will be replacing the Conrod, then change the piston ring too. I will suggest to run it first, but you also need the gasket set and o ring set as you took it apart.

These engine are critical with leaks, they will not tune right.

Regards

kenh3497

I checked as soon as you posted the link and of course it was already spoken for. I have a lead on a stubby NMP adapter. I may be able to cut the header pipe off my busted header and graft it to the stubby adapter with some Teflon tubing which the PO of my airplane was so kind to provide extra of. Another guy on RCG has some used stuff but he won't respond to his PM's or emails. That is rude in my opinion. If you want to sell it, respond, or don't post it!!

Ken

kenh3497

I'm making some repairs to the engine cowling. The PO had a hole just behind the engine for glow plug access. It was about 1 1/2 inch triangular shaped hole.

My question is concerning cooling airflow. How much air should directly escape the engine cowl and how much air should continue to cool the pipe tunnel? In my mind 100% or very near 100% should be forced down the pipe tunnel for cooling the tunnel. Thank you.

Ken

I should add this air frame has two exits in the engine cowl on the sides of the engine bay directly behind the side air inlets. So these two exits may account for 40% to 50% of exit air. The pipe tunnel has quite a large hole at the rear of the plane. This hole has been modified it looks to accommodate several different pipes. I may reduce the size of this opening a bit or at least clean it up so it looks better. I also plan on blocking off the side inlets, so all the intake air has to pass over the engine.

flywilly

My Feedback: (121)

Hi Ken,
The 'rule of thumb' is twice as much outlet area as inlet area for cooling air. Baffles inside the cowl to direct (force) the air over the engine can be helpful, too, but often unnecessary.
-Will

kenh3497

I always use 3 times exit to inlet but twice really should be OK. This engine has run very hot as the inside of the crankcase is completely coated with varnish. The crank ring had seized to the crank and lightly scored the crankcase. I don't think it ran that way, just from being turned over by hand. I think that will be OK. The back plate and disc valve were scored. Both were salvageable and will be reused. Refinement of the cooling system will take care of the heat issue.

Currently all the parts are soaking in the crockpot overnight.

Ken

kenh3497

Another plea for help..... & dammit I thought I could a real pattern plane in the air at a reasonable cost.....

Does anybody have a junk DZ engine with a good pump or a junk pump that I could rob some parts out of? Actually all I need is one of the springs for the check valves. One of them wore through and is basically broken in half. I already need $100 in parts (con rod, piston ring & crank ring) and if forced to buy a pump assembly will be spending more that this motor is worth considering the condition of the rest of the engine.

Thank you!

Ken

kenh3497

My problems are solved. At least the high dollar problems. I now have a second "parts engine". I'll get a very nice motor out of the two. Thank you for the help.

Ken

kenh3497

I was able to get a very short maiden on the Smaragd today. Nice take off and about 20 feet up the engine coughed, backfired and died. To high to make a strait ahead landing without hitting the corn ear high (worst place to hit corn this time of year), not enough altitude to turn and land on the field.... Tried to "float" it in above the corn ears....With five seconds of flight time/experience with this plane I got it to slow and the old snap spin happened with enough altitude to get it inverted. It hit the ground at about a 45 degree angle fully inverted. Broke the nose completely off the air frame at the firewall, Fire wall is compromised, destroyed the spinner ( from the backfire and crash), bent the header. The floor is gone all the way back to the wing tube. The good news is the wings are still undamaged as is the horizontal and vertical stabilizers.

I'm not sure what I'm going to do at this point. The fuselage is a lamination of Kevlar and a VERY thin layer of foam and then glass cloth maybe 1 oz??? The foam layer, at least to me complicates a repair as the glass has delaminated from the foam in a few spots next to the break.

I was so excited, now ready to kick the world in the hind side.

flywilly

My Feedback: (121)

Ouch! That just s*cks! The fuselage can be fixed (I've seen photos of similar damage repaired - in the K-Factor, I think), it just requires some jigs to ensure alignment and then making the actual repair with glass cloth and epoxy. Some weight will be added, but it doesn't have to be a lot. You might be able to get a new fuselage; read the 'help needed' thread here. You could scratch build a new fuselage from wood using the existing remains as a guide. Or build a Lightning or Insight from plans/kit which can be done pretty inexpensively. Lastly, make sure the engine will run reliably and the fuel system is 100% airtight. Nothing flies better than a pattern ship; so I hope you will persist!

kenh3497

I'm considering all of the above. I have four or five sets of plans of different F3A air frames on hand. I went through the whole fuel system from clunk to the fuel injector and the engine ran well the day before on the ground. Idle to full throttle and back without a hiccup or hesitation. Can't explain what happened except the engine obviously went lean. Maybe it had an air bubble in the line or a chunk of crap was on the wrong side of the screen in the NEW fuel filter????

I'm going to take a close look at it in the next day or two and see what a cooler head can ascertain. My busy season has just kicked into high gear so any meaningful work will be put on hold for a bit. 12 to 13 hour days don't leave much time for anything.

Ken

kenh3497

We had some rain so got off work early today... I started looking at the nose section and removed the engine from the mount. I pulled the fuel lines off and found a sliver of silicone plugging the inlet of the fuel filter. It looked like leftovers from the manufacturing process. I had installed all new lines from clunk to engine. I did flush the lines but must have missed that one piece I feel better that it was not my engine tuning but something relatively out of my control. It doesn't fix the plane but.....


A few photos of the damage...

kenh3497

I've started a repair thread over on RCG in the F3A forum. I find RCG to be more user friendly when it comes to posting photos.

http://www.rcgroups.com/forums/showt...1#post35899674

Ken

kenh3497

Well, I've made it this far. I need to fill in the low spots, install a new firewall, new landing gear plate and squirt some paint on it along with about 1000 other little things I haven't thought of yet.



Ken

kenh3497

What should be the minimum prop clearance for the average 2M plane? I'm installing the new landing gear plate and currently have right at 2" of clearance in a level attitude.

Ken

jetmech43

My Feedback: (9)

That should be enough clearence

kenh3497

I worked a little more and am at 2 1/4" of clearance. Now I just need to do a bunch of measuring so the LG plate is level with the wing. Then cut the fuse to allow the gear to slip into the fuse. Slow but sure progress.

kenh3497

Not a huge issue but I would like to move the throttle servo behind the C/G to help with an already existing issue made worse by my repair. If this were a sport model with a solid engine mount I'd just use a cable or wire. Can I use a cable or wire with a soft mount? My gut says no. At least not without some "special" linkage forward of the firewall.

Thanks

Ken

drac1

My Feedback: (4)

Sure can Ken.

I use a 1/32" piano wire push rod inside a Nylon tube that is around 1/8" ID. Support the Nylon tube so that it stays reasonably straight. It doesn't need to be dead straight, that's what the clearance is for, so it doesn't bind. You don't want a pushrod that is too solid with a soft mount.
On the servo arm, I use a Dubro mini EZ connector, https://dubro.com/products/mini-e-z-connector. On the throttle arm, a Dubro 1/16" nylon ball link, https://dubro.com/products/1-16-threaded-ball-links.

I've always run YS's and have used this set up on all my pattern ships going back 16 years without any problems.

My new ship, the Xareltoo, has the throttle servo behind the CG and works fine.