T

trib

Well Known Member
Getting ready for first flight and I would like to know what to anticipate for initial engine temperatures (CHT's). I performed the engine run-in procedure on ground with temps in the low 80s and had to secure when CHTs reached 350F, splitting the 10 minute total time at 1400 into two periods of 5 min. Initial flight will have temp around 50F so will have some more cooling. I'm hoping to keep CHTs below 400F with plan to land if temps approach 450F. Can a few of you give me feedback on what kind of CHTs you saw for the first flight of a new engine? I'd appreciate it if you recorded the CHT at takeoff (following taxi/run-up), climb and when stabilized at 75% power for engine break-in procedure. I'm not sure what to expect and this will help:)
 
Depending on which engine but in general If it is a new (unbroken engine) expect a bit of higher temp then normal and you ought to limit your ground run ups to a minimum. I think temps in the lower 400 (400-410) should not be of any concern while climbing but once you are in cruise, if things are setup right (with baffles, etc) they should run in mid to upper 300s, maybe a bit higher during breaking period.
Your CHT will always be higher on the ground as there isn't much cooling provided while on the ground.

Good luck and enjoy the first flight
 
Hi Tim...

...and how is VaBeach these days??? I grew up there, just outside the traffic pattern for NAS Oceania.

My new Superior O-360 initial runs (North Carolina, 95 outside air temps, no wind condition) brought the CHT's up to 450 and I then shut down the engine. The next runs were to bed-in the brakes, and the CHT's were a bit lower. I put less than 30 min on the engine before the first flight.

First flight was great, CHT's were less than 400, oil temp was 195, all at high power settings, and OAT was 90. I have 8 hours on the engine, need to balance the CHT's at this point. Unfortunately, I am "stuck" in my father-in-laws' house right now...20 miles north of OSH. And, yes, this has been my first blizzard.
 
ECI, correct?

Hey Tim,
I spoke to the regional ECI rep last February when I was getting ready for my first flight. He said that you really want to keep it as cool as possible. One or two run-ins (maybe 3 if needed) but all should be really short. I asked him about the 3 minute time limit (up to 4 with the ECI nickle-carbide cylinders) and he said to keep it even shorter, if possible. This guy was very smart...he definitely knew what he was talking about, so I followed his advice. I used the ECI run-in/break-in guide as my maximum guideline.

My CHT's took between 1 and 2 hours to drop...and they didn't appear to drop much. Maybe 25 F, on average. I would recommend you not do any more run-ins and just fly it. The ECI rep said that after starting, take off within 3 minutes and keep the throttle and mixture all the way in. Make sure your climbout isn't too steep so that your engine is being properly cooled.

Best of luck! Let us know what happens!
 
Sonny,

Run-ins are done- Mahlon gave me a schedule he has used in the past. What I am looking for are the first flight temps you saw. I'll be minimizing taxi, and the next start (hoping for saturday) will be for the initial flight. Reread the initial post for the temps I'm looking for.

Sorry that I didn't mention the engine is an O360, 180 hp.

thanks
 
I have done four first flights/new engine. The CHTs stayed in the high 300-low 400 range. It is best if you can put an hour on it at full throttle/mix rich for cylinder break in. Your oil temps might get up a bit but I wouldn't worry if they stay under 230-235. The temps will go down after the first couple of hours. Remember above all else FLY THE AIRPLANE! Also have fun, nothing like piloting a brand new airplane on its first flight. Don
 
Hi Tim,

I first flew my Eci 0360/RV9a back in March of 2006. Outside temps were in the high 60s. I flew it like Eci recommended--throttle and mixture to the firewall for the first 30 minutes and I kept the altitude around 5K density to run a high power setting. The highest cht I saw was 418 F. The second and third flights showed decreasing temps. Sorry -- I did not record the cht at take off!

Hope this is of value.

Cheers,

db
 
Tomorrow's the day!

Thanks for the feedback guys. Based on your info, I'm expecting low 400's. Since the temp expected for tomorrow morning is a brisk 32F, hopefully it will be a little lower even and won't be a concern. :D Plan is for an hour long first flight to get the ECi recommended time of 65-75% power for 45 minutes on first flight to help initially seat the rings.
 
Good luck Tim!

There is NOTHING--I repeat--NOTHING like the first flight of an airplane that you built with your own two hands!! When you line up for take off, push that throttle in, and that airplane literally jumps off the runway you are going to be one very focused but happy guy. There is really no way to put the feeling into words. I was actually "hung over" the following day after my first flight from the adrenalin rush.

Be careful, insure you and the airplane are ready, and enjoy yourself!!!!

Let us know how it goes!

All the Best and as always,

Cheers,

db
 
Tim,
I have a TMX 180 on my 7A. I currently have 112 hrs on it. I did all my first 8 hours at full throttle. Initial CHTs were around 385-425 in straight and level flight. They started to drop slightly as the hours continued. A year later I see CHTs around 335 in cruise. Temps can go past 400 on initial climb out.
Three of my cylinders were close to each other in temps., around 20 degrees. #4 early on was 50 degrees more than the others. As time went on #4 slowly decreased. Now all cylinders are within 20 degrees. Do not baby your new engine.

Looking forward to you first flight report
 
High 300's here.

Hi.

CONGRATS to you on this day!!! It's REALLY something to take your own airplane up on the very first flight! It's something you'll NEVER forget!

I've an Extreem IO-360 built by Eagle Engines and I saw temps in the high 300's during breakin.
CHT's dropped 30-50* after approx 8 hrs of flight and within 5 minutes of eachother.

Here's what it says for breakin instructions in the manual I got with the engine:

100% mineral oil only, acc to OAT.
Normal runup except that prop-cycle to max 100 RPM drop and minimum ground time.
Normal t/o at full power, full rich mix.
Shallow climb, watch CHT's for overheating. Reduce power if nec.
The first hr: level flight at 75% pwr. Observe engine limits. Keep oiltemp beetween 180 and 190*F.
Second hr: vary pwr beetween 65 and 75% every 15 minutes.
Avoid long decends with crz RPM and low MAP.
After ldg: check engine for leaks and discrepancies.

Subsequent flgts: fly at 65-75% pwr and lean to 75*F ROP until breakin occours.
Keep oiltemp beetween 180 and 190*F.

CHT never exceed 500F.
Max service life: CHT below 430 during high perf crz and below 400 during eco crz.
Optimum: CHT 300-400F

Based on this, I flew a 2 hr long first flight at 25/2500, and after that continued with 2 hrs flights until breakin.

CHT's on 75% during the first flights where in the high 300's and mid 300's at 65%.

Once again: GOOD LUCK on the first flight! Looking forward to the report!
 
how much oil

I'm waiting on weather for my first flight, but it occurs to me that I need to buy some more mineral oil to add during break-in. How many quarts typically are needed/consumed during break-in before I go with regular oil?

Don't want to buy more break-in oil than I need and have it sit around unused for ever:)

Jeremy
 
I have 8 hours on the Hobbs right now.

I started with 8 qts of mineral oil. Right now I am down two quarts. Part of this "shortfall" came from replacing the spin on oil filter (just checking for metal). I do not remember how much came out of the filter, but it did not seem to be that much.

I have noticed a variance in the oil level as indicated on the dip stick. If the engine has sat for several days, it indicates abt 1/2 qt more than if I check it right after a flight. I am assuming that the difference is what drains back into the crankcase when it has a chance (oil cooler + crankcase splash).
 
That is a question that can not be answered. Each engine is different and it depends on how you run it. When the engine oil consumption levels out the break in is done. You can continue to use the break in oil till you run out of it and switch or continue to use it. It will do no harm to the engine.
 
Tim,

One other thing to keep in mind. Your senses will be hyper sensitive on your first day. Mahlon reminded me that you will smell paint and other things burning off the engine. This is normal. Just keep an eye on the engine parameters and FLY the plane.

Also, I suggest you turn off all the engine alarms but low oil pressure. You will be watching the engine gauges anyway, so no need to be constantly resetting the alarms.

I hope by now you have made that first flight and all went well!
 
Thanks Bill and yes the first flight is history. I put hour 11 on the plane today and then did an oil change. Everything is going great. I posted the first flight here:

http://www.vansairforce.com/community/showthread.php?t=51725&highlight=n621tr

CHT's are now down to about 320 at 2300 cruise, with all within a 5 degree spread. Initially about 375 and 20 degree spread. A 1/2" tab in front of cyl 1 and the washer behind cylinder 3 baffle brought everything together.
 
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