Craig23

Craig23

Well Known Member
Hello everyone,

I made my first flight today, with a new engine that I need to break-in. It is a 180 hp Superior IO-360 with vertical induction, one slick mag, and one P-Mag. I was a little concerned about some of the temperatures I saw today in the 56 degree air and wanted to get some opinions about whether or not I need to make any changes.

The CHTs in my front two cylinders, #s 1 and 2, were running hotter than 3 and 4. When I first started my climb at full power I was at about 29" and 2660 rpm according to my EFIS. The CHT for cylinder 1 maxed at 432 and #2 maxed out at 429. #3 was at 403 and #4 at 398. My IAS at the time was about 125 knots. I pulled the power back to 24 squared and got my airspeed up to about 150 kts. The CHTs then went down 384, 397, 370 and 362. I have the vertical plates that come with the Van's firewall forward kit attached to my baffles right in front of cylinders 1 and 2. I'm considering removing those plates to let more air by those cylinders, but I've also been told that new engines tend to run hot. What do you all think?

The other question I had was about my oil pressure and temp. My oil temperature climbed to 200 degrees in the 56 degree air. My oil pressure at max power was in the high 70s. A local builder suggested that the pressure should be higher and the temperature lower. Once again, what do you guys think.

Thanks for any suggestions,
 
Craig23 said:
Hello everyone,

I made my first flight today, with a new engine that I need to break-in. It is a 180 hp Superior IO-360 with vertical induction, one slick mag, and one P-Mag. I was a little concerned about some of the temperatures I saw today in the 56 degree air and wanted to get some opinions about whether or not I need to make any changes.

The CHTs in my front two cylinders, #s 1 and 2, were running hotter than 3 and 4. When I first started my climb at full power I was at about 29" and 2660 rpm according to my EFIS. The CHT for cylinder 1 maxed at 432 and #2 maxed out at 429. #3 was at 403 and #4 at 398. My IAS at the time was about 125 knots. I pulled the power back to 24 squared and got my airspeed up to about 150 kts. The CHTs then went down 384, 397, 370 and 362. I have the vertical plates that come with the Van's firewall forward kit attached to my baffles right in front of cylinders 1 and 2. I'm considering removing those plates to let more air by those cylinders, but I've also been told that new engines tend to run hot. What do you all think?

The other question I had was about my oil pressure and temp. My oil temperature climbed to 200 degrees in the 56 degree air. My oil pressure at max power was in the high 70s. A local builder suggested that the pressure should be higher and the temperature lower. Once again, what do you guys think.

Thanks for any suggestions,
Click to expand...

Congrats on your first flight, Craig. I think your temps are fine...they should drop after the rings seat. Your airspeed was kind of low, which is probably why they got up to the 420's. Mine never went over 405 or so, but I flew at around 170 mph for the first 3 hours and never let off the throttle. I didn't lean the mixture at all for the first 50 hours, either. I'd fly it a couple more hours to see if the temps drop and stabilize.

As for your oil temp & pressure...those numbers are fine. Keep in mind your airspeed was low. In a slow speed climb for an extended length of time, my oil temps will get to 225 F.

Aside from my opinion, you really should look at your manual for min/max temps, break-in instructions, etc. My opinion is based on my experience and is probably different than what you would see, to some extent. But, your numbers seem pretty normal to me.
 
Craig23 said:
Hello everyone,

I made my first flight today, with a new engine that I need to break-in. It is a 180 hp Superior IO-360 with vertical induction, one slick mag, and one P-Mag. I was a little concerned about some of the temperatures I saw today in the 56 degree air and wanted to get some opinions about whether or not I need to make any changes.

The CHTs in my front two cylinders, #s 1 and 2, were running hotter than 3 and 4. When I first started my climb at full power I was at about 29" and 2660 rpm according to my EFIS. The CHT for cylinder 1 maxed at 432 and #2 maxed out at 429. #3 was at 403 and #4 at 398. My IAS at the time was about 125 knots. I pulled the power back to 24 squared and got my airspeed up to about 150 kts. The CHTs then went down 384, 397, 370 and 362. I have the vertical plates that come with the Van's firewall forward kit attached to my baffles right in front of cylinders 1 and 2. I'm considering removing those plates to let more air by those cylinders, but I've also been told that new engines tend to run hot. What do you all think?

The other question I had was about my oil pressure and temp. My oil temperature climbed to 200 degrees in the 56 degree air. My oil pressure at max power was in the high 70s. A local builder suggested that the pressure should be higher and the temperature lower. Once again, what do you guys think.

Thanks for any suggestions,
Click to expand...

The temps are fine for break-in, and are typical of what you'll see in steep climbs. I typically maintain climb speeds at 140 knots or better, which helps reduce the temperatures even more, while maintaining a pretty good rate of climb.
 
Keep your speed up

Craig,

Congrats on your first flight! I have almost the identical setup you have; Superior IO-360, vertical draft induction, one Slick mag...but I have 1 LSE III.

Check your Superior break-in procedures. It's been awhile since I did mine, but I'm pretty sure your numbers are fine (and pretty much what I remember with mine). I do recall it called to run the engine WOT or at least 25" squared until the rings seat.

If you didn't get the break-in info from Superior I can .PDF you a copy.
 
CHT Temps

G'day Craig,

I suspect my baffle instructions state that the vertical plates should only be fitted if flight test indicates the need.

Your instructions may include the same recommendation.

Regards,

Bob
 
Agree. I think those numbers are fine.

I recall the front two cylinders also running a bit hotter at first and wondering if those baffle front plates should be removed. But now after break-in, the temps equal out in cruise.

My opinion...it's too early in the life of your new engine to make changes like removing those front plates.
 
Congrats on the first flight. Sounds like all is going well. The temps are in the ball park. The engine will cool down as it breaks in.

With regard to that front cylinder baffle piece, I've been thinking about drilling a few holes in the #1 piece rather than remove it to allow more air across that cylinder. #1 peaks first in climb, about 40F ahead of the other 3. In cruise it settles down almost even with the others - strange.

I have the CHT limit set at 400F with EIS so when the alarm goes off, I try to keep it from going much higher. That's way below the 500F limit but it won't hurt the engine. In cruise the temps are always in the mid to upper 300's depending on OAT.

I was concerned about burning 14-16 gph at full rich during break in until one day I received a private message from a guy who knows his stuff - he suggested leaning slightly to 1300 egt. That made me feel better with regard to wasting fuel and the engine broke in just fine. It did not take long, maybe 10 hours, the determining factor, it used little of no oil at all. The current oil change cycle is at about 40 hours and I've added 2 quarts.

Good luck with your break in and phase one flying.
 
David-aviator said:
I was concerned about burning 14-16 gph at full rich during break in until one day I received a private message from a guy who knows his stuff - he suggested leaning slightly to 1300 egt. That made me feel better with regard to wasting fuel and the engine broke in just fine. It did not take long, maybe 10 hours, the determining factor, it used little of no oil at all. The current oil change cycle is at about 40 hours and I've added 2 quarts.
Click to expand...

At the altitudes I fly at, starting at a 4600' msl airport altitude...........I leaned as usual right off the bat. If I didn't lean agressively, as I didn't a few times, I could count on fouling a few plugs.....which would easily show on the next mag check. As it turns out, my engine broke in very well. Little oil use, and performs strong.

For me (at these higher altitudes), that means the engine only sees full rich at startup. It's immediately leaned as soon as it kicks over; leaned again before takeoff, and throughout the flight as required.

L.Adamson -- RV6A
 
Temp differential

I've always been a little concerned about temperature differential across a cylinder. Somehow it doesn't seem right to me to have the front cylinders on each side being blasted with cold air from the inlets, while the back side of the cylinder is getting air that's been warmed somewhat. I also can't see how the air coming in the front has to make a 180 deg turn around the sharp edge of that front baffle to flow down the lower front portion of the cylinder without separating. I would think that the cylinder is warping into a less than circular shape as a result. I made individual ducts on each side that go above the cylinders and have openings that are over and sealed-to the push-rod tubes. I ran carbon fiber from the push-rod tubes down each side of each cylinder to force the air to flow equally front and back through the fins and then to an opening in the bottom. On mine, I mix the exhaust with the cooling air right below the cylinder, but even without that, by having the carbon fiber come to an opening on the bottom of the cylinder with curled-back eges to promote smooth, non-turbulent air flow out of the baffle and to the opening at the back of the cowling, the cooling efficiency will be much higher, allowing smaller inlets and outlets, and more-even temperatures front-to-back on the cylinders. Of course, there will still be a top-to-bottom differential, but keep in mind that the air has mass, and will stay to the outside of the fins as it goes around the cylinder, and will extract heat from the fins and not the barrels themselves! 'Just trying to stimulate the thought processes!
 
My superior 180 double slick ran hot to begin with too. However, I was flying in 90 to 100F temps in Las Vegas last May. I had to cut the front cylinder baffles down quiet a bit. Especially the right side. In fact I suggest taking them off to start with, and adding aluminum ductwork tape cut to a similar shape, as needed. When you get the temps you want, then cut your van's supplied front baffles to the same size and reinstall.

Have fun with your new bird, and congratulations...:)
 
Craig,

All the temps and oil pressure seem fine. The only thing I would change is the 29" manifold pressure. Thats pretty high if your EFIS is correct. I would shoot for 25 squared for break in.

Pat
 
I ran my engine today during my first taxi tests. I saw CHTS around 250-350 while taxiing and when I sat and did some high power stuff the temps went over 425. I was surprised how quickly the temps climbed. I have run it twice on the ground, but I think I am going to go airborne next time I run it.

It was about 80 degrees and no wind.
 
Be careful

apkp777 said:
I ran my engine today during my first taxi tests. I saw CHTS around 250-350 while taxiing and when I sat and did some high power stuff the temps went over 425. I was surprised how quickly the temps climbed. I have run it twice on the ground, but I think I am going to go airborne next time I run it.

It was about 80 degrees and no wind.
Click to expand...

Max temp should not exceed 350 for ground runs.
 
JonJay said:
Max temp should not exceed 350 for ground runs.
Click to expand...

I hear you. I won't be doing any more ground runs. ECI says 400 F on CHTS max during ground runs. I am not advocating getting it that hot. However, what I am saying is that I had to taxi to a run up area about 100 yards from my hangar (to get into the wind) and though the temps were around 260 or so by the time I got there I thought it fine to continue. I went to 1800 rpm to do a mag check, temps around 350, then went to full power 2200 rpm or so. I stayed at full power long enough to check fuel pressure, flow, amps, etc. Maybe 5 seconds. temps went rapidly over 400 and by the time I backed it down and temps reversed their trend I think I saw 425. Believe me I wasn't thrilled to see high temps. However, having built the ECI kit myself, I felt compelled to do a full power check prior to my first flight.
 
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