Questions from a new PA .61 user

Hi Guys! I just started flying my GEO XL. It is powered by a PA.61 on a pipe. I am using Sig 5% fuel and a Bolly 13-4.25 2 blade prop. I am using a 6 oz. Sullivan rectangular plastic fuel tank. I have 4 questions.

1. On a 6 oz. tank what kind of run time should I get? I am currently getting 6 min., 20 sec. I would prefer a little longer run.

2. How do you get an engine to stop cleanly at the end of the flight with a rectagular plastic tank? My fuselage is too narrow to angle the tank at all.

3. My rear pipe mount is a Dave Brown mount. The foam padding that came with the mount deteriorated. With it hurt the pipe to wire tie it to the mount without any padding?

4. Is it necessary to use after engine run oil at the end of the day? I am using a Bru-line filter. Can you put engine run oil in after removing the filter?

Jim DeYoung

>Hi Guys! I just started flying my GEO XL. It is powered by a
>PA.61 on a pipe. I am using Sig 5% fuel and a Bolly 13-4.25
>2 blade prop. I am using a 6 oz. Sullivan rectangular
>plastic fuel tank. I have 4 questions.
>
>1. On a 6 oz. tank what kind of run time should I get? I am
>currently getting 6 min., 20 sec. I would prefer a little
>longer run.
>
>2. How do you get an engine to stop cleanly at the end of
>the flight with a rectagular plastic tank? My fuselage is
>too narrow to angle the tank at all.
>
>3. My rear pipe mount is a Dave Brown mount. The foam
>padding that came with the mount deteriorated. With it hurt
>the pipe to wire tie it to the mount without any padding?
>
>4. Is it necessary to use after engine run oil at the end of
>the day? I am using a Bru-line filter. Can you put engine
>run oil in after removing the filter?
>
>Jim DeYoung
I can answer question #4.... If you want the bearings to survive you should always use a good quality after run oil after each days flying. Make it a richual. In high humid air, rust will start to form immediatly. Be sure to get enough in the engine to do some good. Tip the airframe on its nose to get it to the bearings and crankshaft. The best way to get it properly lubed is to remove it from the airframe but its not a nessesity. This will insure your bearings stay free and give you consistent engine runs.....

>Hi Guys! I just started flying my GEO XL. It is powered by a
>PA.61 on a pipe. I am using Sig 5% fuel and a Bolly 13-4.25
>2 blade prop. I am using a 6 oz. Sullivan rectangular
>plastic fuel tank. I have 4 questions.
>
>1. On a 6 oz. tank what kind of run time should I get? I am
>currently getting 6 min., 20 sec. I would prefer a little
>longer run.

6 minutes 20 seconds sounds just fine to me. That is our target time. Fuel consumption, however, is determined a lot by the type of set-up you have. What is your rpm, your pipe setting, your venturi, your head shims, your density altitude. For that matter, what pipe are you using? Even that will affect it. And the air filter will effectively make the venturi smaller. A smaller venturi and leaner setting will help fuel economy. However, that is about the amount of fuel that Matt is using and he has a 13.5 inch three-blader.

>2. How do you get an engine to stop cleanly at the end of
>the flight with a rectagular plastic tank? My fuselage is
>too narrow to angle the tank at all.

I am still waiting for the answer to that question myself. Maybe you need to work on that "magic doing a loop when the engine first starts to burp" shut off.

>3. My rear pipe mount is a Dave Brown mount. The foam
>padding that came with the mount deteriorated. With it hurt
>the pipe to wire tie it to the mount without any padding?

Try it and find out. So long as the pipe does not vibarate in the mount it should be OK. Matt has had about 1800 flights on a pipe and never has used a pad.

>4. Is it necessary to use after engine run oil at the end of
>the day? I am using a Bru-line filter. Can you put engine
>run oil in after removing the filter?

Necessary, no. Advisable, yes. The key point is the bearings on the engine. Synthetic oils and residues from your fuel including water vapor can cause rust to the bearings. Once the rust starts you might as well replace them.

>Hi Guys! I just started flying my GEO XL. It is powered by a
>PA.61 on a pipe. I am using Sig 5% fuel and a Bolly 13-4.25
>2 blade prop. I am using a 6 oz. Sullivan rectangular
>plastic fuel tank. I have 4 questions.
>
>1. On a 6 oz. tank what kind of run time should I get? I am
>currently getting 6 min., 20 sec. I would prefer a little
>longer run.
>
>2. How do you get an engine to stop cleanly at the end of
>the flight with a rectagular plastic tank? My fuselage is
>too narrow to angle the tank at all.
>
>3. My rear pipe mount is a Dave Brown mount. The foam
>padding that came with the mount deteriorated. With it hurt
>the pipe to wire tie it to the mount without any padding?
>
>4. Is it necessary to use after engine run oil at the end of
>the day? I am using a Bru-line filter. Can you put engine
>run oil in after removing the filter?
>
>Jim DeYoung

JIM your set up sounds good.
#1 Perfect time If you need more add one of the shims .003 or .005 to the head NOT the cylinder
#2 No need to angle a tank. I always time each and every flight. Just at the right time do a cutoff loop and enjoy the ride home. If your engine revs up at the end of the flight NO big deal won't hurt anything.
#3 Just make sure that your tie down is tight. Change it about every 30 flights.
#4 Yes good practice to oil a $400 engine
#5 Try a 13x4.2 three blade at 9800 rpm's
#6 Are you having fun?

Scott( runs do get better) Riese

>3. My rear pipe mount is a Dave Brown mount. The foam
>padding that came with the mount deteriorated. With it hurt
>the pipe to wire tie it to the mount without any padding?
>
>4. Is it necessary to use after engine run oil at the end of
>the day? I am using a Bru-line filter. Can you put engine
>run oil in after removing the filter?
>
>Jim DeYoung

Jim,

In my Impact with a PA-.40 and a Smith-Werwage pipe I also used a Dave Brown pipe mount near the rear of the pipe and the foam pad on mine also went away after about 20-30 flights. So I just skipped the pad, put a new ty-wrap on and snugged it down tightly and flew it that way. Periodically (probably about every 30 flights or so) I put on a new ty-wrap and keep flying. The Impact has a little over 1,500 flights on it now and the pipe shows no fretting wear at all.

>
>>3. My rear pipe mount is a Dave Brown mount. The foam
>>padding that came with the mount deteriorated. With it hurt
>>the pipe to wire tie it to the mount without any padding?
>>
>>4. Is it necessary to use after engine run oil at the end of
>>the day? I am using a Bru-line filter. Can you put engine
>>run oil in after removing the filter?
>>
>>Jim DeYoung
>
>
>Jim,
>
>In my Impact with a PA-.40 and a Smith-Werwage pipe I also
>used a Dave Brown pipe mount near the rear of the pipe and
>the foam pad on mine also went away after about 20-30
>flights. So I just skipped the pad, put a new ty-wrap on
>and snugged it down tightly and flew it that way.
>Periodically (probably about every 30 flights or so) I put
>on a new ty-wrap and keep flying. The Impact has a little
>over 1,500 flights on it now and the pipe shows no fretting
>wear at all.

Sometimes, however, no padding results in a leak right in the area that touches the mount. Servo-tape self-destructs pretty rapidly, so I started using cut-up pieces of header coupler. The gray kind from MACs works the best - cut a piece the size of the mount, then split it in thickness with a single-edge razor blade, and Hot Stuff it to the mount. Then cut a hole in the middle to get to the bolt. Lasts forever.

>>
>>>3. My rear pipe mount is a Dave Brown mount. The foam
>>>padding that came with the mount deteriorated. With it hurt
>>>the pipe to wire tie it to the mount without any padding?
>>>
>>>4. Is it necessary to use after engine run oil at the end of
>>>the day? I am using a Bru-line filter. Can you put engine
>>>run oil in after removing the filter?
>>>
>>>Jim DeYoung
>>
>>
>>Jim,
>>
>>In my Impact with a PA-.40 and a Smith-Werwage pipe I also
>>used a Dave Brown pipe mount near the rear of the pipe and
>>the foam pad on mine also went away after about 20-30
>>flights. So I just skipped the pad, put a new ty-wrap on
>>and snugged it down tightly and flew it that way.
>>Periodically (probably about every 30 flights or so) I put
>>on a new ty-wrap and keep flying. The Impact has a little
>>over 1,500 flights on it now and the pipe shows no fretting
>>wear at all.
>
>
> Sometimes, however, no padding results in a leak right
>in the area that touches the mount. Servo-tape
>self-destructs pretty rapidly, so I started using cut-up
>pieces of header coupler. The gray kind from MACs works the
>best - cut a piece the size of the mount, then split it in
>thickness with a single-edge razor blade, and Hot Stuff it
>to the mount. Then cut a hole in the middle to get to the
>bolt. Lasts forever.
>
> Brett

Brett,

Using the MACs gray header coupler as padding is a good idea and I think that I will start doing just that as a preventive measure. However, I leak test my pipes about every third ty-wrap (90 to 100 flights or so and have yet to find a leak with my PA-.40s. I know that PA-.61s tend to generate more vibration and heat in the pipe (I saw Ted's pipe melt-down at the '98 Nats) and may lead more readily to leaks. Worth checking, in any case.

I cannot really say anything about pipe lengths etc that someone else hasnt already said.
I can say that make sure the engine is broken in properly it seems that even after break in the engine still changes some after some flights.

I can ask what kind of fuel are you using?
When I use Powermaster it seems that any engine i use it in sputters and coughs or what not a lot more than when I use Sig.

I am sure that someone will say I am wrong and say that it happens with Sig as well and maybe it does but in my experience and burning a lot of fuel over the last couple of months the sig has yet to do any kind of or very little sputtering etc and putting powermaster in the same engine results in the funnies.

Hehehehe you are probably already using Sig

Jim,
I use a bit of paper towel between my pipe & pipemount maybe 4 thicknesses thick..
John

We used to use a little piece of fuel tubing between the pipe and mount, helps dappen the vibration, also. John Lindberg

Here is what I do for a "clean" end. I take the clunk and bevel it on my grinder (a file would work too). I cut the bevel so that it just touches the pickup hole. I then use my xacto to carve the the hole completely open on the bevel side. I think you want the natural "spring" of the fuel tubing to just have the clunk just "kiss" the side of the tank.

I get the approximate bevel angle by looking at how it touches the wall when the tank is plumbed up. It seems to work for me.