Day at GAMI

[Dave Siciliano]

Well, finally got the P-Baron to GAMI to have them check fuel flows and see what can be done to tweek the plane. The left engine was running a little rough.

First flight test showed one GPH difference in fuel flow between the first and last cylinder to peak on the right engine. On the left, there was a three gallon per hour difference. Found fuel injectors were on the incorrect cylinder on the left. Switched them back and the left engine ran really rough; so, we are checking the work to see all was done correctly, then, going from there.

Dave

 

[Richard]

Well, finally got the P-Baron to GAMI to have them check fuel flows and see what can be done to tweek the plane. The left engine was running a little rough.

First flight test showed one GPH difference in fuel flow between the first and last cylinder to peak on the right engine. On the left, there was a three gallon per hour difference. Found fuel injectors were on the incorrect cylinder on the left. Switched them back and the left engine ran really rough; so, we are checking the work to see all was done correctly, then, going from there.

Dave

Wow! what a difference. Do you mean the injectors were removed and then replaced but on a different cylinder? GAMI warns about that.

 

[Let'sgoflying!]

mine are numbered, stamped.

 

[AirBaker]

Wow! what a difference. Do you mean the injectors were removed and then replaced but on a different cylinder? GAMI warns about that.

But he was 'at' GAMI.

I've got to have mine looked at. I've got a pretty even set of EGTs, but they could be a little better.

 

[Richard]

But he was 'at' GAMI.

I've got to have mine looked at. I've got a pretty even set of EGTs, but they could be a little better.

Dave knew it, I knew, we all knew it. My comment wasn't so much towards Dave, rather it was that some mechs working on complex planes like Dave's yet don't pay attention to the details.

 

[Dave Siciliano]

Yes, the GAMI jectors had been placed in the incorrect cylinders. Don't know how it occurred; we did have a mechanic recently clean the plugs and injectors. Don't know if he just put them back the way they were (and they were incorrect to begin with), or it he errored. But, they weren't where they were supposed to be.

We put them back where they were supposed to be (and you are correct, they are numbered--but can be difficult to see--and there is a corrosponding number on the injector).

Funny thing, when we put them where they were supposed to be, the engine ran rougher!!
They had flowed the injectors to be sure they all performed properly. Downloading the data after a test flight showed the egt spreads on the left engine were three gallons apart.

Today, we are confirming the location of each probe to be sure we are getting proper readings; then, looking at other issues to see how we can get the peak temps closer together. This engine has always run just a little rougher than the right engine and was difficult to run LOP because by the time you leaned the last cylinder, the first to peak was very lean (too lean).

So, we've been running about 65% power in cruise (2,300 rpm; 30" of MP and about 13.5 gph) where it would be difficult to harm the engine even if you were running it incorrectly.

To run a little more MP and fuel flow on the lean side, we will have to solve this problem. And, of course, it's better to have it running correctly if possible.

There's a real aysemetric air flow issue on these engines (WBs). The air comes in real close to 2,4,6 and has to go way around the engine to get to 1,3,5. The data we collected shows 2,4,6 peaking together; then, 1,3,5. So part of the solution may be to adjust air flow in some manner.

Best,

Dave

 

[Dean]

Dave, Which mechanic at GAMI is working on your plane? I am related to Caleb(CAD operator) and good friends with Luke and David. We are flying there this weekend for Christmas with the wifes family. Arriving friday afternoon and leaving Sunday, weather permitting.

 

[Dave Siciliano]

Dave, Which mechanic at GAMI is working on your plane? I am related to Caleb(CAD operator) and good friends with Luke and David. We are flying there this weekend for Christmas with the wifes family. Arriving friday afternoon and leaving Sunday, weather permitting.

Hi Dean:

David has supervised some of the work. Met the actual guy changing the injectors but don't know him. George and I are flying the plane together today. We'll see what he has to say.

Dave

 

[Dave Siciliano]

Dave, Which mechanic at GAMI is working on your plane? I am related to Caleb(CAD operator) and good friends with Luke and David. We are flying there this weekend for Christmas with the wifes family. Arriving friday afternoon and leaving Sunday, weather permitting.

Dean:

I said hi to David. He said you were coming in this weekend! Small world.

Well, GAMI worked their magic on 233KS! Spent 2 1/2 days there. Did three test flights with George. We got the left engine to run smoothly and they did some things to cool a hot cylinder.

We test flew today and did a LOP climb 35" or MP; 2550 rpm; all cylinders cool and fuel flow of 17.5 gph. Climbed between 6 and 700 fpm have almost half the fuel flow of a book climb!!

Leaned it our in cruise: 35" of MP; 15.5 gpy 2150 rpm. Trued out just under 200 knots at 10,000 feet. I formerly got this performance closer to FL200. Can't wait to get this up to altitude to see how it performs on a trip!!

Best,

Dave

 

[Richard]

That is good news. What I would have given to be there to see Dave's reaction to the improved performance. I know they say not to worry too much about it but I am curious what the dif is.