slskn

My Feedback: (4)

also, when the engine was last running, I noticed a ticking sound, after I shut down thinking it was the rod that fell out as to why it was ticking, ( which was the number 5cyl.) at the bottom, I later discovered (after a day or so) that the ticking was from the top cyl. number 1cyl., and it was the valve itself that was stuck down, and then when I turned the prop by hand the piston would tap the valve and then pop back up making the ticking sound that I heard when it was running,. after several turns it still was ticking, (I could see that the valve would stay down after the rocker arm came up), so I put a few drops of oil on the valve and spring, and it then began to work normal without sticking, I hope it was just dry thus causing it to stick? and not a bent valve?-Steve

Orion09

My Feedback: (1)

If you want a little right thrust you will need about a 1/4 in. more clearance on the left side to center the prop.Pete

pappy 883

My Feedback: (2)

This is true Tom, I'm just a stickler for precision. Not only with the side play but the shaft to rocker arm fit. During the first valve lash check the measurements were all over the place. The arms moved around so much the arm would wander off center of the top of the valve stem. After i installed & test ran my 7-77 with the rocker shaft shims installed it did take out a lot of the guess work out of the re-checking of the valve lash.
(The end play on my old Harley is only .002" the shims come in .002" increments.) you can see why i found .018" alarming .

slskn

My Feedback: (4)

ok I just spent all day re-doing the valves and did find out that when the rocker arms are to one side or the other, the valve lash is different, so I went with the minimum thickness which I used a 004 mm gauge, and set it at that, when finished with all 9 cyl. oiled the rockers and fired it up, ran beautifully but did notice at least one of the rocker arms moving back and forth just as fast as the rods were moving up and down, so I too am wondering if the rocker arms should have a shim or two so there is not so much play from side to side, some of the rockers arms were perfectly still, maybe not to worry about it? not sure, but did run great!, also I am kind of confused as to having to check the lash 4 or 5 times over for each cyl. that`s 45 or so times checking the lash, because the position of the cam lobes, I thought as long as the valves are totally shut and the piston is at top dead center one time of setting each cyl. should work, seems to run good so hope every thing is OK?-Steve

Maxam

My Feedback: (62)

Steve you must adjust to the highest lobe. If you do not, a valve may not seat all the way and thus get burned. -Tom

pappy 883

My Feedback: (2)

Just to clarify,,,,,," Quote from the 7-77 manual
"Because the cam gear of our engines is a shared cam gear with all the cylinders and rotates at 1:6 ratio, thery're actually 6 differant positions on the cam gear that need to be checked "

Maxam

My Feedback: (62)

That would then be three cam pairs at 1/6 speed. There are 5 I believe for the 9-99. -Tom


Pete???

Heli-NuBee

I took my UMS Evolution 7-77 radial engine out to play today. I took my 7-77 powered BH corsair out to our flying field to let the guys see it and finish up the engine break in runs. Several of my fellow club fliers have been waiting to see the engine and plane and all were impressed. The engine ran great and I have now finished the break-in process. I have about two hours of run time on the engine and I believe it is enough to now fly the plane. However, the plane will not fly until I solve the retract landing gear system problems. See the BH Corsair forum for details.

Roger

Heli-NuBee

I think that I finally got the retract issues ironed out so if things go well, I may have the maiden flight on my UMS 777 radial engine powered Black Horse 91" Corsair tomorrow.

Roger

77chickenhawk

Yahoo. Take video

Pull Up Now!

My Feedback: (3)

I purchased 4 quarts of 99.8% pure methanol. I planned to mix this with a gallon of FAI fuel, no nitro. Will this work for breakin on my UMS-Evo 077? Thanks!

pappy 883

My Feedback: (2)

If the FAI fuel is 18% syn. oil, you should be good to go.
The 18% oil mix won't hurt at all for breakin for a couple of tankfuls, it just makes a oily mess. I would save your Methanol for the second hour of breakin .....anyone? They recommend 10% oil for breakin down to 7% minimum for after .

nilsreinert123

Yes that will work i use 5%oil95%metanol in my 735 and have flown about 12 litres through it. I have the engine in a 2.2meter Monocoupe now ,flew it alot this weekend and it is a very realistic plane in the air ,and it sounds very cool! You get the typical radial sound also at higher RPM's unlike Saito 90r3 and ASP400

pappy 883

My Feedback: (2)

Good luck with the maiden......(double check the C.G. !!!)

Heli-NuBee

Hi Guys - Roger the Radial Rabbit here (thanks for the nickname Tom). Well, I did it - my UMS Evolution 777 radial engine powered Black Horse Corsair is not a virgin anymore. The maiden flight was awesome! The plane flew like it was on rails and the engine ran great. Even the retracts operated well. The only thing that was not perfect was the fact that the Robart War Bird 3-3/4" wheel covers both came off and the video only showed the ground, the fence and blue sky. No takeoff, landing or flying on the tape at all. I just haven't been able to find one of our guys that can take video of RC flights. We did get a short video of the startup, taxi and the first attempt at takeoff. The plane really wanted to go to the right and I had to kick up the rudder into high rate for the second attempt at takeoff. I could then keep it running straight and true. The plane really floats on landing and is really a real *****cat. I took a lot of effort to get the plane here but the effort was worth it. I am looking forward to many more fun filled flights. Our War Bird show is in two weeks and we got this plane in the air just in the nick of time. Here are a few still pictures of the plane at the flying field this morning and a link to the taxi video. http://www.youtube.com/watch?v=ix9yo...ature=youtu.be

Roger

Maxam

My Feedback: (62)

Way to go Roger Rabbit Radial!!! Told you it was the perfect combo.......Tom

Pull Up Now!

My Feedback: (3)

Three of the forces acting on an airplane to keep it from going straight Are P factor, slipstream, and torque. These are all left turn in forces, are you sure the plane wanted to go right? If it's true, I saw this same thing at a recent Minnesota airshow. In that case the plane actually taxied at takeoff speed into the pit area full of people. Maybe too much engine offset?

Linkan2

Hi nilsreinert123
do you have any video on your Monocpe & UMS 7-35??
Lars

skypup50

Wow...that sounds great!

skypup50

Well guys, I have a 1/5 Pica Waco kit 72" span. I need help. I have decided I definitely want the 4 stroke sound and a low end rumble. It's between an os 160 twin or the evolution 7-35. I have the 7-35 on back order. Would I be taking too big a chance with the radial and its only 1 year warranty? Thanks for the help.

nilsreinert123

Hi Lars! Sorry ,no video yet.

I would'nt worry about wearing out the engine ,it is more plausible that a crash will kill it than run time

Pull Up Now!

My Feedback: (3)

Can't find this Methyl Hydrate at Home Depot. Anyone else able to find it there? I got mine from Amazon.com, amazingly.

Orion09

My Feedback: (1)

Its available in any hardware store in Canada but its controlled inthe states.

Maxam

My Feedback: (62)

Skypup, It is a nice reliable engine! -Tom

skypup50

Tom

I was concerned and then found this thread. Glad I did. OK...so I see guys scrounging for fuel. What do you use? Will it be a problem. I was wondering what fuel consumption might be on the 7-35? Thanks for the help!