First engine run with propeller

[Pttim]

I just couldnt resist. I got my daughter to sit on the turtle deck and the wife to video tape what was about to happen.

I fired it up and let it idle, Idle 850 rpm. Every thing seemed ok so I ran the throttle up, brakes were holding fine at 1800 so I ran it up some more. She topped out around 2800 to 2850.

Propeller is Sterba 54 x 42 engine single port 1835 Zenith carb. Single mag. ignition.

Am I in the ball park or do I need a few hundred more rpm?

Comment's please.


Thanks

Tim

S2L (single seat)

 

[soneraifred]

Tim:
I'd suggest that you read the "Normal" Static RPM string under the Sonerai Airframe Discussion Board. John Monnett's recommendation back in the good ol' days was 2900 rpm minimum static. Mine has always been in the 3100 rpm range.

Before you go changing your prop though, make sure that your timing is correct, and that your carb is set right.

 

[Pttim]

Fred,

Read it and wanted to post it there, but i was rushed. Agreed not ready to do anything with the prop yet. Check max stop, adjust mixture, like I said I think I'm in the ball park.

To tell you the truth I was a bit nervous myself , I believe it was still building rpm, it was the last glance I took With the daughter hangning off the back.. Im shooting for 3100 to 3400. Secondary ignition should help. No? Will try again

Tim(no spell check)

 

[Jerry A.]

Tim,
The secondary ignition should give you ~200 RPM. Do you know what your compression ratio is?

Jerry

 

[Pttim]

I do not know what the compression ratio is . I purchased the engine complete with carb & intake used, previous owner reported approx. 200 hours flown in a Sonerai. The owner replaced this engine with a 2180 in search of more power because his field elevation was @5000 feet in Utah. After replacement of the engine he didnt feel his gain in power output offset the cost of the new engine and installation.

I will run it up again tonight after double checking that I am actually getting wide open throttle.. It is rather hot out here in PA. I believe OAT yesterday was high 80's low 90's and pretty humid when I ran it.

I also need to hook up my cylinder head temp and oil temp & manifold pressure guages before I do any extended run ups.

There have also been comments as to how the intake manifold that I have was constructed with sharp 90 degree bends. (See gallery). These bends probably dont do much to enhance smooth flow, but since it flew like that before I thought I would try it as it is.

Tim

 

[Pttim]

Two more runs made today, the first topped at 2950 rpm. Leaned mixture a tad, second run achieved a max of 3040. with the addition of the secondary ignition I should pick up 100 to 200 rpm I hope. It looks like I am within the window now.

Tim

Also two sucessful driveway taxi's wooo hooo that was fun.

 

[Gaston]

Hi Tim

make sure your valve lash is correct at .006" when cold.
I did notice a difference between .006" and .008"
with my 1835cc at 7.3:1 CR,and I also see about the same variation with my 2276 at 7.5:1 CR.
I talk about 50 to 100 RPM(tiny tach RPM)this may be only a meter issue but I tend to beleive what instruments say,and say again...
mixture plays a big role too...

note that this is FREE Power and performance

Gaston

 

[Pttim]

[yt=425,350]CHacL5Chruo[/yt]


A link to a video of engine run

Tim

 

[Pttim]

Here is another video of the first taxi in the driveway.

Tim
[yt=425,350]xF1abu6rWaU[/yt]

 

[splischke]

The engine sounds good Tim -- and you have a heck of a long driveway . Now get that thing covered and flying!

BTW, good to see the safety precautions of the weight on the tail and the assistant following the aircraft.

 

[ltusmcret]

Hi Tim!!
Your video is great and the engine sounds fantastic!! Just one question, though?? How come you had the 2x4 chocks BEHIND the wheels?? Be glad that your poor daughter didn't bail during the hi-speed run!! Just bugging you - just jealous! I wish that I was at the point that you are!!

Claude

 

[Pttim]

Daughter on the back. not the smartest thing I've ever done. She's a good girl, she forgave me for lighting her on fire when we tried to get my old tractor running.
:

Thanks for the kudo's because that just re-kindles the flame to keep moving forward. The chocks were behind the wheels because the driveway slants back to the garage. I wanted to make sure the tail wheel was staight in case something let go. Subsequent runups were done with a strap lashed to the tractor. I was much less nervous knowing that I was'nt going to shoot down the driveway with my daughter riding piggyback. Probably the reason I gained 200 rpm over the first runup.

Lots to do yet! Thanks for all the support you guys!!

Tim

 

[FarmerTim]

is anyone else laughing a little ;D

 

[phzabriskie]

Ah yeah, my granddaughter would not be half so brave I think. Great video Tim. Wish I were doing taxi test.
-Pete

 

[Pttim]

The more I look at that video, not sure I would have sat back their either. Both my daughters have always lent a hand when I needed it. Reminds me of a time when the lawn mower would'nt start and I could'nt (would'nt) check the spark and pull the cord at the same time. I just asked my oldest daughter, she was prolly 6 or so, she gladly held the spark plug wire while I gave the rope a tug. You could tell from the look and the reaction I just needed a new spark plug.

A few years later same thing with the youngest daughter you see in the video, I know I'm bad. They still love me though.

P.S. You only get one spark per kid, those of you that have more than two kids are in luck, you can fix a bunch of lawnmowers.

Tim