Granpooba

My Feedback: (5)

Ernie,

The check is in the mail. I know a good deal when I see one !

Sbach342Guy

Finally decided to convert to e-power. After several failed attempts at getting my IC engine to run correctly I've given up. The last couple of weeks has been spent researching electric motor options. I'll be getting an EMAX 4030BL ( think that was the model number) and a HobbyKing ESC. I've already got a bunch of 6s batteries so I should be in good shape there. There is a chance I might even be converting my 30cc Sbach to electric. My last flight with the Sbach was a dead stick landing that ended with my landing gear being ripped out which did a fair amount of damage to the fuse. Pilot RC offers FREE replacement laser cut wood to fix the damage! All I have to do is pay for the shipping. The dead stick my have been my own dumb fault though. I might have run out of power in the ignition battery. I need to check the charge on it to see if the dead stick was my fault. If so, I might keep it a gasser.

ahicks

My Feedback: (2)

RE: running out of power on the ign. battery? That causing the engine to quit completely not likely. When the ign. batt gets low, they get weird, but they don't shut the ign power off. They'll almost always idle at least! Usually allow for like 1/4 throttle? When you try to power up beyond 1/4 is when you'll see it messing with you, acting for all the world like it's running out of gas? FWIW...

Good luck on the electric conversion!
-Al

Sbach342Guy

Just checked the battery about an hour ago. It was nearly fully charged.

wjcalhoun

SBachGuy
Sorry to hear of your IC troubles.
As Al said, low ign battery generally presents as missing with advancing throttle, or failure to rev up. Not usually a dead stick. That sounds like fuel delivery or metering. Engine too lean, leaks in fuel delivery. If you are having trouble with all your gassers, maybe you should check with a gas-knowledgable pilot at your field to check things out. My experience with gasoline has been extremely positive. My glow engines are reliable as clockwork.

microdon2

My Feedback: (47)

SBach- Is that a DLE 30 in your Sbach? Has this engine ever run properly? Were you at idle when it died? I do love gassers, but that have lots of moving parts (with the carb) and can be a pain to troubleshoot engine problems. Just checking - did you look at - high speed too lean, vacuum leak (hoses, loose carb, hose off inside tank, fueling port leak, carb rebuild needed, etc). Also I was told on the DLE 20 and 30 the reed block does not sit exactly flush, making low end idle rough, if possible at all. This can be fixed by sanding it on a piece of glass. In the meantime I use a higher idle while in the air, then cut that before landing. Just some thoughts.

wjcalhoun

Sbach
Mike is right - many 'moving parts' with gas, which is why i do suggest that you get with a knowlegable gas flier; too little information from what you write to make a real diagnosis. it has to be setup or tuning, because these engines have been pretty reliable for most of us.

Sbach342Guy

It had been running fine for about two dozen flights. No dead sticks at all. I run telemetry on the Sbach and there were no temp issues. I've heard of people having problems with the ignition module. The Revolver on the other hand sat for over a year w/o being run. I had several people look at the engine. I even tried a new carb in it. I've got three other planes that are electric. A 41" Edge, a 48" MXS, and a 60" Extra 300. Never a single problem. Plug in the battery and go. No tuning. No mess. No clothing stains. Better throttle response. Shorter flight times for sure. I have completely given up on the 30cc...but I'm close. Any plane under 30cc will definitely be electric from now on. 30cc and above get expensive and really starts getting limited flight times. 30cc is kinda on the fence. One of the guys in my club has been flying for around 40 years. He converted to all electric a couple of years ago for the same reasons....reliability. It will be nice to get the Revolver in the air again soon.

microdon2

My Feedback: (47)

Sbach - Might I suggest starting a discussion thread here on RCU on your specific engine and the problem you're having. No doubt you'll get valuable feedback from people who have years of experience. The fix might be simple, just something you haven't tried yet And are you also having problems with the gasser \ nitro engine on your Rev 70? If that's a gasser it may be the same issue. If it's a nitro engine then it's probably tubing or tuning. Nitro engines (as you know) are much simpler and easier to tune. If it's a four-stroke nitro then it could be your valves need to be adjusted. I just did that for my OS 1204s - it was way out of spec - and MAN did it make a difference! The engine was running VERY rough before (after it had run fine for a while) but now, after adjusting, its' got almost double the power! Or it could be as simple as you need a new glow-plug. Or your fuel filters are clogged (goes for gas or nitro).

On the gas side, are you comfortable taking the carb apart and inspecting? If not, try it - they're not that complicated. Could be as simple as gunk or grit clogging the strainer. Or you may need a rebuild kit, where you replace the pump membrane. I've heard that the Ethanol in gas dries these out, so they should be replaced every year or so.

I know electrics have some advantages. But I'm one who loves the reality of having a working combustion engine under the hood.

ahicks

My Feedback: (2)

I know you've had your problems, but regarding this thing quitting, I'm just wondering if have you taken into account that the cooler temps this time of year will require a carb adjustment? Even if it was running perfectly when it was warmer, even if there isn't a darn thing wrong with it? The cooler air is much more dense, requiring more fuel to burn properly. Not a lot more fuel, but enough to where it may cause you headaches just like this one....
-Al

Sbach342Guy

I've already opened and cleaned the carb on the DLE-30. The fuel filter was clear so no issues there. It was in the mid 70's when the engine died on me. It was probably in the low 80's the last time I had tuned it. It has an optical kill switch but it is on a dial so it is hard to accidentally hit. Idle was around 2600 RPMs and WOT throttle was close to 8000. Temperature seems to stay around 265F. Transition from low to high or high to low was smooth. It is a bit baffling considering how long it had been running w/o issues. Even if I get it running again I don't know if I can trust it. I've got close to $1500 in that plane. My electrics have never failed me. The only reason I'm even considering keeping the DLE-30 is cost. It will be around $350 to switch to electric.

The Revolver is definitely getting converted. It's currently nitro and switch to electric is only $100 because I already have batteries that will work with it. I simply don't have the patience to troubleshoot the Super Tiger 60 any more. Three other people have already looked at for an hour each. No dice. Electric conversion will only take an hour and there is no tuning involved! It will simply work.

markhamregular

I would like to hear from those who have an OS 120AX 2 stroke on their Rev 70.
I thought the plane would be screaming but it's just OK.
I have to say the engine has only 10 flights so far, so not completely broken in.
I tried a 15-8 prop, but I did not like the speed, so I tries a 14-10. Same speed.
Someone told me the 120AX was underpropped for a 14, so I changed it to 15-10.
Still find the plane's speed just OK.

Anyone with 120AX our there with any suggestion. Thanks,

microdon2

My Feedback: (47)

markham - what brand of prop are you using? There's a big difference in efficiency in brands of the same size. Props I would NOT use - Zinger, Master Airscrew. Good \ very good - APC. Better - XOAR, Vess. I'm sure there are more that I don't know about.

For that engine I'd think a 15x10 would be about right for speed, 16x8 for more vertical. Maybe the engine's not broken in yet, or it's not tuned just right. Are you sure you've got it dialed-in for maximum RPM's? You might also want to start a thread here on RCU on this engine.

JoeMamma

mark,

Here's a great place to start http://www.rcuniverse.com/forum/m_3998256/tm.htm

Joe M.

markhamregular

Joe,
Thanks for the link. I have a tach but never use it. I will try so I can compare with others.

Micro,
I use APC props. They are my favorites. Someone suggested that I use the "Sport" line. I just cannot find any sport one the size I want. They don't make 15-10 Sport. So I use the "Pattern" line.

Thanks all,

wjcalhoun

Mark
I had that combination on my first R70. The engine was well broken in, as it had flown quite a bit on another airframe. I flew an APC 15x10 and 16x8 prop with excellent performance, both on the vertical, and with figures and maneuvers.

My 'perception' is that the second R70, with DLE20, performs a bit better despite the same nominal displacement, and a few extra ounces of weight. My R70/DLE20 is now propped with an APC 14x12 and is QUICK.

My advice is to be patient until the 1.20AX breaks in. Tune the HS needle each day you fly, because weather conditions (temp, barometric pressure, etc) will change, and as the engine breaks in better, it will run well with a leaner HS needle and give you more RPM. It is an outstanding engine; starts reliably if you choke it. I am just using the standard OS #8 glow plug. I still have one pulling around my 1/4 scale Extra 260 (10.5#) very nicely even though it could have a 30cc gasser up front.

JoeMamma

mark,

As I mentioned in an earlier post, I have both a Hangar 9 Pulse 125 and a 70" Hangar 9 Ultra Stik that are both equipped with 1.20AX's. The 1.20 is a fairly large engine for any .60 size plane. The 1.20AX WILL eventually break in after about 2+ gallons have been run through it. Then it's a real powerhouse !!

Both these planes get thrashed pretty hard[X(][X(], and consequently I noticed some cracks and separation at the firerwall, so if I could recommend, make sure you do some reinforcement in that area. Just a little extra insurance.

Joe M.

orthobird

My Feedback: (1)

hi, i am using a saito 125 4 stroke nitro engine, and the plane is a screamer. top speed is 124 mph.

orthobird

My Feedback: (1)

where are the gurus? i need your help.

microdon2

My Feedback: (47)

Orthobird - I'm guessing that's 4-40 rod? Was it working fine before and bent all of a sudden? If you don't have your pushrod going through the gray guide tube (and with 4-40 it probably wouldn't fit) you might want to reinforce with a carbon fiber sleeve. Or you can always move both servos to the back for minimal pushrod length.

Ernie Misner

Where are the guide tubes? They appear to be way too short, leaving the inner rod too long and flexible. It appears the guide tubes should at least be long enough to be glued into that last former that is visable. If I'm on the right track there are some fixes without actually having to replace the guide tubes. You could slip and glue carbon fiber hollow rod over the exposed pushrods to make them stiffer. Or at least epoxy some tiny eye bolts onto that last former for guides for the push rods.

Luchnia

My Feedback: (21)

+1 Guide tubes important for this setup.

wjcalhoun

Quickest fix is probably to cover with carbon fiber tubes, as mentioned; put epoxy on the rod, and slide the tube over; very stiff and very light, and probably willl work. Actually with the carbon fiber, you MIGHT get away with 2-56 rod, instead of 4-40 rod, and save some weight.

My personal preference for this situation is just what microdon suggested: move the servos aft; build in two beams to hold the servos, fix the covering, and you are good to go. There are pictures of this kind of setup earlier in this thread.

Ernie Misner

Why don't other Revolver's have that problem with too much exposed pushrod?

ahicks

My Feedback: (2)

Many are gas, have the servos in back?

With nitro power though, that may cause a balance issue? I'm like the carbon fiber plan for that option...