beachbrada

My Feedback: (17)

Im working on a Aeroworks Edge 540 and the engine blind nuts come preinstalled so that the engine will sit at 45 degrees inverted to allow for the stock muffler to fit under the plane into a channel/void under the fuselage. The only problem I have with this setup is it will require alot of cutting into the cowl to get the 125 in this postition. So I am considering mounting the Saito completely inverted and purchasing a inverted pitts muffler for the engine. Since I have never changed how the blind nuts were installed on any of my ARFs Im wondering what are some guidelines/rules for doing this. Also Ive heard if you have any problems with a engine. mounting inverted will only magnify them if not create more problems. Will a [link=http://www.ironbaymodelcompany.com/index_files/Page438.htm]Iron Bay Regulator[/link] help?

Gray Beard

My Feedback: (-1)

I knock the blind nuts out if they are in the way then plug the wholes with dowel and epoxy then drill new holes and install new blind nuts. If you are having problems with the engine then going inverted isn't going to help at all. I invert mine all the time wothout any problems, the fuel tank just has to be installed correctly and sometimes I have to lean out the low end just a touch. The fuel tank can creat problems if too high or low, I don't use a regulator but it could help if you can't get the tank close to level. I also make up a remote glow driver from mono head phone jacks so I don't have to be reaching under the plane to install and remove my glow starter.

w8ye

My Feedback: (16)

Gray Beard has good advice. I've changed a lot of motor mounts and it never gave any trouble. Re-read his post several times and don't miss the part about tank height

beachbrada

My Feedback: (17)

The engine is new and hasnt been broken in yet, I just didnt know if inverted engines tend to have more problems. But mostly I just wanted to know how to go about drilling the new holes for new blind nuts? What measurements am I going to use to make sure I drill in the right spot. What do I need to take into consideration to do the job right?

w8ye

My Feedback: (16)

You can determine the C/L of the current mount on the firewall and make the C/L of the new mount set in the same place on the firewall.

The spinner will still need to set in the same place at the end of the cowl

Stick 40

when I have inverted any of my Saito's I try and not put them right on inverted, like just off maybe 5 to 10 degree's if I can. This will help keep the fuel from sitting on the flow plug and putting it out.

But the best is a on board glow system to keep the fire going, this will save you a lot of dead sticks and your idle will be the best.

As for the blind nuts, I would plug the holes with some round balsa and glue then redrill the holes and put in new blind nuts.

You could put screws in the holes with some locktight, you may decide to go back to them. Then redrill and put new blind nuts in.

sticks

jetmech05

on board glow or be ready for some dead stick time

Gray Beard

My Feedback: (-1)

I still have my on board glow driver out in the shop still in the package, I think I bought it about 10 years ago. I can't remember the last time I had A dead stick with any of my four strokes, inverted or upright. Once you correctly set up and tune the engine it doesn't know it's installed upside down. The reason I have the on board dirver was I kept hearing how hard they were to keep the glow heat on an inverted four stroke, then I was taught to tune one. Sticks idea of off setting the engine a few degrees sounds like a good idea if you have problems getting the low end set correctly. The Saitos come out of the box with there needles set really fat for break in, you may want to break in your engine on a stand and upright then lean it out so you are close to the correct settings. I just broke in a Saito 100 upright in an old plane then set it up in an Extra inverted, in this case it took no more adjustment on the low end but that doesn't happen often. So far no dead sticks.

beachbrada

My Feedback: (17)

After giving it more thought and reading all your posts Im going to leave it as is and try to do as little cutting as possible. But I did go ahead and order me a iron-bay regulator. I will go ahead and drill my mounts then use it on a stand of some sort and tune it off the plane.

bigtim

My Feedback: (13)

I'm with GB on this one everthing exept I use primarally OS 4stroke engines, every one without exeption is inverted,without a glow driver, I havent had a dead stick yet, my club members who have saito engines have nothing but praise for them as well,break it in upright an then invert it for your plane if your worried, but you shouldn't.

I wouldn't use balsa dowl better to go with some hard wood dowel to plug the firewall, in case you need to screw somthing to the fire wall and it happens to land on that spot,it always seems to happen that way to me.

as for your exhaust check out the header adaptor from RC Specialties he sells it here http://www.rcuniverse.com/market/item.cfm?itemId=449034 which works with the stock muffler, he also has a turbo muffler also http://www.rcuniverse.com/market/item.cfm?itemId=446628

nobodytwo

GB is absolutely right on the money. I have several Saito's from 80 to 180's. All these motors are completely inverted or with the head down and run fine without on board glow drivers. Have never had a problem with dead sticks! Using Saito plugs, fuel with 10 - 15% nitro.

Happy Landings!

bingo field

I think we are looking at " how to install the engine inverted, and maintain the centerline" . Looking at the engine mount, how would you rotate it 45deg. and still have the engine mounted in the proper location? Locating the fuel tank for proper draw is the second problem.

beachbrada

My Feedback: (17)

Apparently it can be done, in another thread that is specifically about the Edge 540 there is a guy who posted pics of the mod. The only thing is that he doesn't go into detail on how he took his measurements to keep that centerline and ultimately make a precise new mounting location. And another bad thing is that his posts are from 2005 and I don't think he comes onto the forums anymore.

I screwed on the engine mounts in the stock position and put the engine on it so I could see exactly how much cowl I will have to cut away. And it doesn't look too bad now, it looks like I will only have to cut some small holes so the valve covers can stick through. Originally I thought I was going to need a large hole to allow the entire head to fit through. My new problem is that to stay within the max distance from firewall to prop washer I need to have the engine so far back that the throttle arm is touching the firewall. One pic shows the arm completely aft and the other shows it completely forward. Will I have to move the engine forward a little or can I get away with it like this. Any ideas?

dragnbye

your right doesnt look to bad but if you want to go upside down then do it(it will look better) also rember 3to1 rule for cooling mounting it inverted would allow more to of the cowl to be cut with out really seeing it. and for the fuel reg and the glow driver dont wast your money. a properly tune 4 stoke can run just fine any way it will never know the diffance. i do alot of 3d so i ilde alot, i have the 125 on a funtana and it's a great combo on your plane it should be down right awesome

bigtim

My Feedback: (13)

brada its easy, simply bisect the old screw holes with some pencil marks.

draw lines crossing at the center of the mount location,from the existing screw holes, where the lines cross this is your pivot point.

where the lines bisect, you make a line across the firewall side to side this is your center line,also make a vertical line,if you have a triangle it helps so you have a perfect 90o lines so you have your new reference lines in place.

then mesure the distance between screw holes they won't change,and mark the new holes.

EX; if the holes are 1 1/4" apart then 5/8" on each side of the center line is where the new hole locations are, the center line won't change your just rotating the mount on a axis.

then if you want your engine slightly off center say 5o or so, its very easy make your horizontal line off,but still bisecting the crossing center mark, and draw your vertical line 90o from that, and the mount will still remain in its center location.

just mark the holes equally on each side of the lines according to the distance of the holes on the mount.

I got a little beach in me bra LOL

2slow2matter

My Feedback: (1)

You don't need onboard glow if you set it up right. Onboard glow is a crutch. The only reason to use onboard glow is to aid in starting the engine, not to keep it running. You will need some sort of remote glow system, be it onboard with it's own battery, or a cheaper remote glow locator that you plug your driver into for starting. This is because with an inverted engine, it's difficult to get under the plane to put the glow driver on, start it, then get the driver back off from underneath a running engine.
Saito's have canted glow plugs anyway, so it's not like the glow plug sits in a "bowl" when the engine is inverted. Set the tank up right, get the needles set right, and you won't be able to tell the difference between an upright, side mount, or inverted engine.

opjose

Yup exactly.

The Saitos are - REALLY - tolerant of an overly rich mixture, and I see a lot of people flying continuously with these engines VERY VERY rich... ( wonderful engines btw... )

After youve run the engine for a while ( e.g. a half dozen tank fulls or more ) you'll want to lean out the low end to the point that the engine starts to quit on idle because of a lean condition. Then richen it back up about 1/2 turn and you'll have the low end set very well.

Once you get to this point, siphoning will not be an issue at all, so you can also forgo trying to deal with the often overstated tank height issue.

Prior to this, you'll want to keep your idle a bit high as you are flying your plane initially so be prepared for grass landings to slow it down on the ground.

Otherwise the inverted mount is no different than running the engine upright, albeit getting at the glow plug can be disconcerting for some people at first.

beachbrada

My Feedback: (17)

Man you guys got me thinking. How will I install the new blind nuts. I cant reach the firewall from inside the plane, I'll either have to work through the fuel tank hole or remove the top center wood piece on the firewall. How do these blind nuts stay in place, do they have little spikes like other blind nuts Ive seen? So would I be able to hold it in place then tighten a screw down to suck it into the firewall? Another thing I was unsure about, once I take all the measurements and mark off where the new mount needs to go, can I shift the mount a little up or down on the firewall to compensate for the engine head facing down? Here are some pics of another guys inverted setup on this plane.

w8ye

My Feedback: (16)

They have little spikes

I've put them in through the tank compartment via using a threaded rod of the screw size stuck all the way through the tank compartment from the front. Screw the nut on the rod and pull the nut into place. Use a nut on the outside to draw the blind nut tightly into the wood

opjose

That works....

One of the RC magazines also had a good tip about this.

They suggest cutting a bolt the same size as the threads on the blind nuts, so it has no "head".

Solder a piece of wire on the end of the bolt so the wire is in line with the threads...

Drill you holes and push the wire through the holes so that it can be reached further into the fuse.

Once you can grab it, thread the blind nut on, spikes toward the firewall.

Pull through until the blind nut is against the firewall and the cut bolt is exposed.

Thread a washer and nut on the exposed side and tighten to draw the blind nut into the firewall.

Once done loosen and merely unscrew your gizmo.

This works just great and your "tool" can be used for other planes.

Gray Beard

My Feedback: (-1)

Working on an ARF has it's little problems and you have to work around them. Never go through the top to work on something when you can go through the bottom. Not all blind nuts are equal either. The ones you get in the hardware store are made in a far off land, maybe?? The barbs tend not to hold or they bend when you are putting them in, buy good ones at your LHS in the 4 pack, I haven't had any problems with them. To install a blind nut in an ARF or completed plane can be daunting sometimes, I like that word, daunting instead of a PITA. I have been known to glue them onto my finger, get it behind the hole then get my screw with washers into it and start turning until it seats. Other times I have used all thread and screwed the BN onto it with A couple of twists then run it to the hole and gotten the screw into it and started tightening. The key is to get a screw onto the blind nut and then tighten it until the nut barbs are seated. Every plane is different so you have to do some of that thinking stuff for yourself. Sometimes easy and sometimes hard but you can always do it. Now, about the glow driver myth. Way back in the olden days when four strokes were a new thing people really didn't know all that much about them, mistakes were made by folks that didn't know any better. When a problem like dead sticks reared it's ugly head instead of thinking about the problem and fixing it people came up with other answers to the problem like the glow driver. SHAZAM!!! Problem solved!!! A lot of these problem solvers are still with us today sitting back in the pits and telling new pilots all about how things don't work and how to fix them and the new pilot takes it as fact then tells others so the myth is spread and taken as fact. Then there are other old time pilots that decided to just work through the problem and figure out what makes these new engines work. I was lucky enough to have one of these people to learn from and was shown how to tune an engine and set up a plane. It's all about the set up. Do it correctly and things work, do it wrong and you will need that glow driver. If you need it I can take photos and show you how to make up your own remote glow driver. There is a problem with them too, sometimes the little hot shot glow starters don't have the poop to heat the plug and you sometimes need the added power of a power pannel on your flight box, then you have to contend with that scarry cord I keep hearing about, you know, the one used on starters and power pannel glow starters!!!

opjose

Here, here!

All true, and the last statement sums it up succintly.

beachbrada

My Feedback: (17)

Well thanks for all the info guys, I will see what I can get done on it tonight and get back on here with the update. Also is post 13 I asked what I should do about the throttle arm touching the firewall, anyone got any suggestions?

Gray Beard

My Feedback: (-1)

Throttle linkage, what a pain in the mule!! You can go to DuBro and buy there really cool linkage system or look at there picture of it and make up your own with U-Control bell cranks, that's always fun. You can loosen your throttle arm and move it as far forward as you can get away with, sometimes that works, I do it a lot. You can cut away some of the fire wall so the control arm goes back farther without hitting anything. If you are using a solid rod like 2-56 you can relocate the arm and put bends to the rod so things clear. Something I was told by my first instructor, it's your airplane, you can do anything you want with it. Just sit down and look at your plane and let the gears work in your head and wait for the ideas to show up. Most of my better ideas come to me when I'm in the shower or on the can. That would be funny if it wasn't true. If you look at photo 3 you may notice that it looks like the fellow ground out some fire wall to give his throttle are some room, a few extra holes doesn't hurt anything.

beachbrada

My Feedback: (17)

How about a rod with bends so it goes past the arm then bends back like this?