Zippi

My Feedback: (10)

Guys,

Watch how you bend the tabs. You can bend the tabs up and still not be up against the face of the bolt. If this happens the tabs will do no good. This happened to me the first time I bent the tabs up. Had to bend them down and start over.

Joystick TX

I would not redo the muffler; as long as you have something to lock the bolts they should be okay. The shorter bolts are way less likely to come loose than the long ones. The mufflerholes are also reinforced so they are less likely to wallow out and allow movement between the cylinder and muffer.I'm not a big fan of LockTite, but based on how you did it, I would say the odds arereally good thatit will work. I would say you have nothing to lose by testing it. You can check it after each flight.

PacificNWSkyPilot

My Feedback: (19)

Steve (and Zippi and Jeffin TD),

My thoughts exactly. With the metal flat against the port, and nothing in there to allow it to work loose - like the standoff column in the original muffler - I felt it should hold pretty well. Plus, I searched until I found the real-deal Hi-Temp LockTite (27200). That took some looking. I didn't think the new mufflers were going to arrive in time for flying this past weekend, so I re-fastened my original in place, using the LockTite. Then, of course, that very evening, here comes the new mufflers in the mail. As it turned out, I was taken down hard by the honey-do list this weekend, so in my spare moments, I removed the old one and installed the new one. I could not turn the screws. I had to take a propane pen-torch to the port flange to get the Hi-Temp LockTite to release the screw. Once it started turning, it went fine; but then it cooled off a little, and stopped it again. I had to re-heat it every few turns. This Hi-Temp stuff takes no prisoners, and according to the specs, the engine does not get hot enough when running to allow it to release. It's good to 450 degrees. I'm pretty sure even an air-cooled engine doesn't get above 350 degrees. Some quick research shows 250 to 320 is normal to fairly warm for these engines (120 to 160 C).

I think it'll be good. Technically, this stuff should hold the screws with no help. Besides, I've got my Super Stearman in pieces right now, and that'll be as big a job as I need for the rest of the week, after pulling the other one apart four times this week. (I had to rebuild the GSS landing gear mount and reinforce it some more. Went to brass threads and plastic screws after that.)

I'm anal about getting the tabs flat against the side of the bolt heads, Zippi, on those special occasions when I actually take the time to USE them. . .

Lol.

If I had to choose one of them where they could come loose again, I'd rather it was NOT the Super Stearman. Bipes are tougher to dig into and work on; lots more to them. They're only more fun in the air.


~ Jim ~

Joystick TX

Jim, is the 10-32 a typo? The muffler boltsshould be M5 threads.

PacificNWSkyPilot

My Feedback: (19)

Maybe. I matched them to my taps and dies, then used the ones that matched. Whatever I used worked perfectly. I do know that the Nord-Locks were M5 size, so. . . (This is me being too lazy to go out to my shop and dig around for the tap I used.)

~ Jim ~

Joystick TX

Sounds exactly like what I do, I don't pay that much attention to the actual size as long as it fits correctly.

Hope you get a chance to fly more now that you're caught up a little.

One thing that got me up early today was because whenI wasreading your post on the muffler installation last night I wanted to look up the muffler bolt size in the manual to be sure and I noticed that the engine timing was 30 degrees BTDC. I had an ignition module failure a while back and I have this nagging feeling that I may have set the timing at 28 degrees. Got to get out and check it before I go flying again.

PacificNWSkyPilot

My Feedback: (19)

I happened to be out in the shop last night, and I dug around and found the tap I used. Turns out, it was 10-32. I picked up the bolt that came with the new muffler and threaded it in. Nice and firm, the threads fit the bolt with no catching, it felt perfect. When I cleared the threads with it, I used only the tap with my fingers, and I didn't have any problems. I'm sure it was right for the bolt.

I don't think that a two-degree variance in the timing would cause a module failure. Unless you're just saying that your subconscious is nagging you, hinting at the possibility that you might have installed the new module two degrees too advanced. Sorry, I couldn't tell which from the post.

Stuff wakes me up too. It annoys my wife that I get out of bed to go check something out. With me, it's usually some scene in one of my books, that doesn't work as well as I'd like it to, and I get up to rewrite a chapter in the middle of the night. She'll usually find me in my recliner the next morning, laptop gone dark, sawing wood.

~ Jim ~[8D]

Joystick TX

Jim, the module failure was most likely due to age and use. Iput a little over 500 hours of time on it in 2 years. When I put inthe new module, I used the timing wheel for my other engine, which is marked at 28 degrees, to make sure the timing was right. I thought itwas odd that the timingwas off when I put inthe new module, but I just thought it might be due to manufacturing differences. Anyway,I reset the timing with that wheelinstead of checking the manual. About two years ago I made a new timing wheel for the Syssa,whichis marked at 30 degrees and it is marked FOR SYSSA 30cc, so I would have it ready when I needed it. I have no idea why Ipicked up the other timing wheel,guess it seemed like a good idea at the time. Nothing is foolproof to a sufficiently talented fool.

Anyway, I reset the timing this morning to the 30 degree position and will fly the old GSStomorrow to see if there is any noticeable difference in the engine performance. I know I have lost some performance, but it could be due to a combination ofmy airplane gaining weight over the years, due to mods and repairs, the amount of time I have on the engine, wear from some of the oils I tried, and possibly from my timing error.

I do alot of my best engineering when I sleep on a complex problem. My wife also thinks its crazy when I wake up at 2 am and need to scribble down some ideas before they disappear into the brain fog.

PacificNWSkyPilot

My Feedback: (19)

LOL - Especially when you can't even read what you wrote the next morning!

~ Jim ~

Joystick TX

I was wondering how close the two bolts were. According to a post on another forum the M5 and 10-32 are prettyclose.Since the 10-32 is a little smaller, it went in okay when you cleaned out the holes..

An M5 x 0.8 thread, where 5 is 5mm overall diameter & 0.8 is the thread pitch.
5mm = about .197" diameter.
0.8 = .0315"

On a #10-32 thread, the Diameter = .190" & 32 threads per inch = a .032" thread pitch.

PacificNWSkyPilot

My Feedback: (19)

Wow, those numbers really are close.

I just mounted the second muffler. The threads were smooth and clean.

And the tabs are bent up, securing the bolts! I did remove the engine so I could get it. It took some work, but I think it's worth the effort. It sure was easier to work on.

I'll be happy when this engine is back in the Bipe, mounted and secure, all cowled up and ready for flying this weekend.

According to the High-Temp LockTite, 72 hours of curing gives full securing strength.

~ Jim ~[8D]

Joystick TX

Glad to hear you got both mufflers installed okay. Will be nice to know how you like the sound.

I'm on the way to the field to do some flying and test out my new, correct, engine timing. Hope I can tell the difference in power.

PacificNWSkyPilot

My Feedback: (19)

I'm guessing it'll start a little nicer, and run a little smoother. 2 degrees off - that's still pretty close to original specs.

I'll be interested in hearing how it ran.

~ Jim ~[8D]

Joystick TX

Got in four good flights this morning. The timing did make a little difference. With the timing set at 28 deg BTDC my peak RPM was in the 8100 to 8200 range. After the timing was set to the recommended value of 30 deg BTDC the peak RPM was 8400 to 8500. Temp was 87 deg, altitude about 600 ft, prop was a Vess 18.5 x 5.5.

I could not tell any difference in the performance of my Giant Super Sportster. Bummer. Perhaps a plane with less weight and drag would have a noticeable performance increase.

PacificNWSkyPilot

My Feedback: (19)

Joystick,

The GSS is a pleasure craft, like a four-star 40. Sure, it can do some basic aerobatics, but it's not a performance monster and was never designed to be one. Even with the Syssa 30CC which can pull it straight up and up and up, it's only going to do so much. It's still my favorite monoplane. My next favorite is the Pulse 60, which is also a pleasure craft. The GSS can outperform it, though. . . Do you know what I like about my GSS most of all? Killer landings. Smoooooth. I love my flaperon settings.

I just finished ( yes, I know I'm supposed to be writing. I wrote all morning, then took a break...) installing the Syssa back into my GP Super Stearman with the new muffler. Got the cowl on; she's all buttoned up. I think I'm going to do some bipe flying this weekend. Yeah!

Glad to hear that yours is running well with the correct timing. 300 extra RPMs is a healthy boost.

~ Jim ~[8D]

PacificNWSkyPilot

My Feedback: (19)

Didn't get to fly the Super Stearman this weekend. I took it out to my back yard yesterday, gassed it up, and started it. At first I was able to tune it, and it idled good and then accelerated good, but then it started to act up. I tried to adjust it again, but it got worse. So, then I started fresh, two turns on each and tuned it from there again. It wouldn't tune up. as soon as it accelerated, it would die. I did notice that it was "leaning" forward when I accelerated, and made a mental note to check the mounts.

Finally gave up and took it inside, and removed the cowl so I could inspect it. The top mount bolt had come out of the back of the mount, inside the fuselage. Nothing to do but pull it all apart again. I found the screw had backed all the way out, but was still in the firewall. I had a hole drilled right next to it, close enough to reach in and pull the screw forward enough to grab the threads and bring it out front.

Here's where it got interesting. Nobody knows better than me just how full the nose of that fuse is. It would literally take me one or two full days to pull everything out and reinstall it. So I made an executive decision, and cut three holes in the sides and top of the fuse, so I could reach in with an allen wrench and hold the threads of the screws while tightening the mounts. Apparently, the blue locktite I had used on the screws had wiped off going through the wood, or that screw would never have come out like that. Now that I had the mounts removed, and the screws exposed, I used RED locktite on them and tightened them up - REAL tight. Not the Hi-Temp stuff, just the regular red.

I've got the engine mounted again, and I'm going to leave the cowl off and take it outside again for another test run. Not sure what's causing it to die and not tune right. Thinking about changing the spark plug before going out there, since there's not much else I can figure that could create a problem. The same gas I used last week on my GSS, so that's good. And it DID tune up and run great at first, but then it started acting up.

So, that's been my Friday! I'll keep you informed.

~ Jim ~ []

JeffinTD

Vibration can make an engine run bad.

I'd also look at the rubber boot in the spark plug wire. That sure made mine run weird.

PacificNWSkyPilot

My Feedback: (19)

It's not vibration. But I'll check the spark boot. I know it was on securely at the time, but that doesn't mean it was contacting the plug inside, though I did look in and saw the contact end I was looking for. Didn't check it to make double-sure of contact yet.

~ Jim ~[]

JeffinTD

The problem I was having was a crack in the rubber boot, that the spark was arching through.

PacificNWSkyPilot

My Feedback: (19)

I inspected my rubber boot, and saw no cracks. But I didn't run a small flat-blade driver around it to check for hidden cracks. If it had one, it had it from the factory, because this was the first start-up on this particular engine.

I'll still put my money on the spark plug. Didn't get to run it and check today.

~ Jim ~

Joystick TX

Seems like if your engine was loose that movement would bechanging the engine speed since the trottle cable would be stationary.

If that is not it then my bet would be there is something in the carb screen. I had junk in mine when I first got it. Also seen that problem on some DLE's.

PacificNWSkyPilot

My Feedback: (19)

Hmmm. I put a filter on it before I ever started it, but it's no big deal to get to that carb screen, as I recall. I'll check it out.

I'll let you know what I find tomorrow. I'll be checking it out then.

~ Jim ~

PacificNWSkyPilot

My Feedback: (19)

Well, I had a look at the plug cap, and it looks identical to my other one. There a wire entering the center of the "chamber" and a little spring that sits in the cylindrical hole above the spark plug, and below the wire I mentioned. On this one, the spring was not IN the hole, but off to the side, only halfway showing. I grabbed a piece of linkage wire and pulled the spring over until it settled into the hole. No damage to the silicone boot inside, it looks good.

Working on it in between the Honey-do list. Plus, I was foolish enough to suggest going to a movie. Usually she says, "Nah," but today she said,"sure!"

I'll check out the carb screen too.

~ Jim ~

hyflyer9

I would check to make sure that the timing pickup has not come loose and as i found on my engine when one of my stand of mounts came loose it did the same as what you are describing i also found some small metel fileings on the pickup magnet that might have interfired with the propper timing spark.

PacificNWSkyPilot

My Feedback: (19)

Nope, nothing so complicated. Before I started into all that crazy stuff, I decided to start with the simplest and easiest to check. The spark plug was bad. I changed it out, and it's running great now. It tuned right up, textbook easy.

But that was my last spare, so I need to pick up some more replacement plugs.

That's some good news. Now, ***SIGH***, I get to repair the holes I cut in my Stearman. But it was worth it. At least I'm positive that the mounts are solid, the gas flow is good, the spark is good, and the engine runs great.

What kind of gas filter does Todd recommend?

~ Jim ~[8D]