Who didn't build their own engine?

SHIPCHIEF · #1 08-15-2013, 03:20 PM

Just a poke at the traditional engine forum thread: Who built their own engine?
I built my own, after the (now retired) builder of my core engine made a cardinal error, and enlarged the upper spark plug holes on my rotary 13BT engine. These 'trailing' plugs need to have their holes completely covered by the apex seal during its passage over the plug to prevent igniting the intake charge.
Even tho I initially purchased the core engine, the mount, fuel injection system & reduction gear, I did build the intake & exhaust systems, the oil and water cooling systems, scoops, ducts, wire looms, cable ways etc.
a lot of it I built twice, some 3 times!

Non traditional engines are also available from commercial builders, but I think a lot of them are fabricated by the aircraft builder for the pleasure & challenge of doing it?

rv7charlie · #2 08-18-2013, 05:12 PM

Hi Scott,

Bummer about the 'pro' engine builder. But, you now know more about your FWF than almost all 'traditional' engine fliers. And be aware that things just as bad, or worse, have happened to guys flying Lycosaurs when they had 'pros' build their engines. Even L & C have had horrors like batches of brand new bad cranks (C actually had it happen to the 'fix' for their 1st bad batch), and those cranks cost more than your entire core engine.

We will have true experimentals. Most RV's are really EINO's. :-) Where's the fun in that?

Charlie

bret · #3 08-19-2013, 04:20 PM

Quote:

Originally Posted by SHIPCHIEF

Just a poke at the traditional engine forum thread: Who built their own engine?
I built my own, after the (now retired) builder of my core engine made a cardinal error, and enlarged the upper spark plug holes on my rotary 13BT engine. These 'trailing' plugs need to have their holes completely covered by the apex seal during its passage over the plug to prevent igniting the intake charge.
Even tho I initially purchased the core engine, the mount, fuel injection system & reduction gear, I did build the intake & exhaust systems, the oil and water cooling systems, scoops, ducts, wire looms, cable ways etc.
a lot of it I built twice, some 3 times!

Non traditional engines are also available from commercial builders, but I think a lot of them are fabricated by the aircraft builder for the pleasure & challenge of doing it?

That is a very intersting project you have going there!

SHIPCHIEF · #4 08-19-2013, 06:46 PM

Thank you Charlie & Bret;
It's been fun for me, but I don't try to push it on people.
At our EAA326 chapter Burger Burn, I was asked about it in a polite way, because of the engine failing. I told them I don't mind talking about it, I just didn't expect anyone to be interested in it.
I rebuilt the core engine in a few days, and it's back on the plane now, while I make a few improvements I was putting off. I added a large manifold pressure gauge from a Cessna center line twin so I can read Turbo output boost (front) before the throttle, and true manifold pressure after the throttle (rear).
I'm adding a boost Blow Off Valve, home made to keep the weight down. And re-routing some of the engine wires for simplicity and to control RFI. I had some alternator, ignition or injection noise on the COM radio.

rv6ejguy · #5 08-19-2013, 06:57 PM

So Scott, how does it perform? Any numbers?

SHIPCHIEF · #6 08-19-2013, 08:36 PM

Ross;
Thanks for asking, as well as being a consistent advocate here.
I had about 5 hours of ground running, including tethered runs up to 44" Hg manifold pressure.
Cooling required several mods, some of them copied from 'those who have gone before'. Finally I got it to cool itself at idle thru 3800 engine RPM, which should be enough to fly about 100 MPH, 1700 Propeller RPM.
Tethered runs at full boost did show an alarming increase in oil temp, always arrested before exceeding 206 F. This may have been a missed message about the oversize trailing spark plug hole.
After the Airworthiness Certificate was issued, I installed the cowl & covers, and pushed 89SE out for a 'victory lap' taxi, then to put away for careful work-up to the first flight. I taxied down to the run up area, did a normal run-up, took the active runway for a 3 second burst of power, to be followed by a slow down to the turn off.
Well, the forward movement of the aircraft must have allowed the engine to build up more RPM, more exhaust flow, more power (I was impressed!) and as I started to pull back the throttle, came a POP! and the engine shuddered to a stop with grey smoke pouring out of the cowl.
All I can assume, is that the additional RPM allowed by the forward speed created the condition for flash over at the over size trailing spark plug holes, which stretched the rotor housing on the #1 rotor. The alignment dowel at the top, which is also the main oil galley forced the end iron out, cracked it and sent 100 PSI oil spraying, which was the source of grey smoke. The #2 rotor suffered detonation damage to an apex seal, which destroyed the rotor and worthless rotor housing.
I've discussed this with various rotorheads, and reassembled the engine with new rotor housings, a rotor, end iron, seals gaskets etc., so Phase 2 could happen in a week if life's other little adventures don't step in front.
For a second there, I was truly impressed.
Hat's off to Tracy Crook for the reduction gear and Fuel / ignition computer, Craig Catto for the prop, and Fred Breese for the motor mount.

rv6ejguy · #7 08-19-2013, 09:07 PM

Well, thanks for posting your candid tribulations here and the fact that you won't give up easily. Oil temps can be a bear on turbo engines and especially turbo Wankels.

Are you running an intercooler?

Looking forward to your first flight report!

I am finishing off my flight testing now with the new ventral rad which is amazing so far. Still learning and tinkering after 10 years...

I can confirm that my 6A was for "educational purposes". It's been a heck of an education so far.

SHIPCHIEF · #8 08-20-2013, 08:13 PM

Surprised myself;
Got the RV-8 Rotary 13BT running today. Runs like a champ.
I spent most of the day finishing the wiring and checking the tightness of all the fittings, and chasing down NGK BER9EQ and BER7EQ plugs. I only had time to warm it up with all the covers off, and inspect everything.
I only ran it up to 3200 RPM, which was 22"Hg. on the big Manifold Pressure gauge that I added. Electronic Engine Monitors are nice, but the one I have gives mostly text data, hard to see during take off.
Tomorrow I'll go at it some more, maybe I can get it to the power testing and Taxi stage before I have to go back to work. (vacation seems short somehow)

rv6ejguy · #9 09-17-2013, 07:03 PM

Any more updates?

SHIPCHIEF · #10 09-24-2013, 11:15 AM

Slow. Other projects always find their way I front of the RV-8, but I did continue to run and adjust. I set the ignition timing at 4000 RPM, according to the manual, and I tracked down a tiny oil leak at the swivel end of the first oil hose out of the engine. I installed a new hose with non-swivel ends.
I've fabricated a turbo Blow Off Valve to limit boost, It's a modified radiator fill neck welded to the turbo pipe ahead of the throttle body. I'm starting with a 4 pound cap. I also welded in a 1/8" pipe boss, where I tap turbo pressure. I have a twin engine manifold pressure gauge, with coaxial needles, so I can observe turbo pressure vs manifold pressure, and know the differential at the throttle body. This will help me know if the turbo is sized properly.
I'm taking it out to the airport this morning to play with it. Then tomorrow I start my work week, and won't be able to work on the plane for the next 7 days.