YellowJacket RV9

YellowJacket RV9

Well Known Member
Patron
Hi guys -

I had always been planning on a used mid-time engine for my 9A build, but am starting to seriously consider going new so I know exactly what I am getting, even if it means breaking my pay as I go rule. I am currently really liking the idea of a Titan OX-340 stroker.

My real question pertains to properly breaking in the engine while in Phase 1. I understand the two different objectives may be at odds with each other. How many people have experience with this process, and will it be hard to treat my engine right while in Phase 1?

I also understand I could start with a used engine with some time left on it, and then upgrade in a few years. But right now I am working two jobs, and in a few years I will probably be starting a family and that expense would be harder to justify.

I appreciate any input. Thanks!

Chris
 
Been there.... done that.

Hi

I recently did this with my RV4, but an engine I rebuilt myself. I decided breaking in the engine properly was the priority. So for the first half hour circled the overhead of the airfield, then when I had gained some confidence that all was well, climbed and flew out further ensuring I had enough height to glide back home or to a nearby airfield.

Everything was at 2400 RPM which equated to 175mph until I returned to the circuit after a 2 hour flight. I followed this routine of at least 1 hour flights at a min of 2400 for the next 10 hours. I probably had 20 hours on the engine before dropping normal cruise to about 2100.

The good news is that my engine uses very little oil perhaps a quart per 20 hours.
 
Thousands before you have flown their test hours with new motors. It can be done successfully. The titan engine in particular likes to have 75% power in the first 30 minutes then varied per their break in instructions. Dont let phase 1 impact your engine decision. You will love the 340 Stroker. 180+hp in that little weight package is hard to beat.
 
My $.02 - I'd suggest very minimal engine runs - certainly no "taxi testing" (as tempting as it may be). I'd suggest only two; each limited to 2 minutes or 300 CHT whichever comes first. The first run to 2000 RPM - insure it runs, indications are normal and no leaks. Let it completely cool down. The second run, to determine static RPM / insure that you have takeoff power.

I recommend you tow the airplane to the runway (you probably won't be able to meet the 2 minute / 300 CHT limit if you taxi). Full power for takeoff, and when at a safe altitude, very shallow climb rate and throttle back - goal to keep at least 75% power while keeping temps as low as possible. You should see the initial ring seating in about 20 minutes - temps (CHT & EGT) will drop noticeably and somewhere around 30 - 40 minutes I'd conclude the flight to look for any leaks or anything that got loose, etc.

I've done this a few times, and the engines have done very well.

Dan
 
Engine break-in

Send me your e-mail and I'll send you the break-in procedure I was given to use from Premier Aircraft Engines in Troutdale, OR. Worked great for me.... 20 hrs/ Qt.
mikerv9a at gmail.com
 
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