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Help Analyze Cruise Numbers - New Bravo Owner


irishpilot

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Fellow Bravo Afficionados, I am still fairly new to my Bravo and I'm trying to figure out how to get my cruise power setting dialed in. Today I flew three legs in South Texas for a total of 3.0 and the screenshot shows that the CHTs were a little warm, especially the #2 cylinder. I was at 8,500, IOAT of 21C, with half cowl flaps. I ended up running richer to get the CHTs under 400. BTW, the book just says to stay under 500. I assume industry standard is 400 for longevity.

 

From what I've read, I should be able to run 50 ROP with cowl flaps closed and stay below 400CHT. Also of concern is my oil px is 56-57 psi with 8 qts. During the pre-buy, I found that the EDM is new and the mechanic set the initial values and just did a little tweaking prior to the sale.

 

What's going on an where do I start? Thanks!4cd14ee3d0acf7ca6750591707ec83d8.jpg

 

Fly Safe,

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Everything looks a little hot to me given the FF.  How’s your baffling/seals? My oil temps are usually below 190 and PSI a little higher with similar temps here in south Florida.  Especially with cowl flaps half open you should be seeing some lower CHTs.  While there are some different views on CHTs (with some people saying they shouldn’t go higher than 375 at cruise), you certainly want to keep them below 400.

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Hi

I’m a Bravo owner with 1400 hrs Bravo experience.

To my mind at those numbers and low altitude you should be quite a bit cooler egt’s - 360-370. So either timing is out or cooling shroud needs some work.

I would be happier increasing to 100 rop and increasing Tit to 1600 to get the same fuel flow.

0-50 Rop is known as the red box and allegedly bad for your engine although that said less than 75% power any setting should be ok.

if you were trying to run these numbers with your engine at 18000’ your oil temp and cht would be off the chart as there is less cooling there.

Your oil temp should never be that high st such a low altitude- I would suggest get a good A&P to re cowl your engine and check the timing

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Everything looks a little hot to me given the FF.  How’s your baffling/seals? My oil temps are usually below 190 and PSI a little higher with similar temps here in south Florida.  Especially with cowl flaps half open you should be seeing some lower CHTs.  While there are some different views on CHTs (with some people saying they shouldn’t go higher than 375 at cruise), you certainly want to keep them below 400.
I agree it's running a bit hot. I'll check the baffling and seals tomorrow since it's due for an oil change.

Fly Safe,
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Looks a little bit warm. Did the moritz guages get completely removed?  If running in parallel the oil pressure sensor might be in a less desirable location giving the lower reading. 
They were recently removed prior to the sale.

Fly Safe,
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When I first bought my Bravo my cylinders temps were elevated but not as high as yours.  I installed new baffle material  in place of supplied  factory junk.  That helped quite a bit.  A lot of work but worth it.  You might turn up the oil pressure a little bit.  If you are using Aero shell 15-50 in the summer the pressure will be low.  I use 100W all summer.

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Let’s invite [mention=7354]donkaye[/mention] & [mention=11242]mike_elliott[/mention] to the discussion too...
-a-
Thanks@carusoam. I'm going out to the plane in a few hours and will pull the cowling and take some pics. Also will have our A&P take a look on Monday.

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IP it’s easy for the right frontside baffle to get bent down good chance you’ll have to replace that section. A msc put my cowling on and flying home I noticed an increase in my cht’s it stayed with a permanent crease once I changed it all was well again.

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We checked the baffles and ensured no folding in the wrong direction. Temps are a little better, but oil temp and #2/3 cylinders are running hotter than I'd like. This is what I was running today at 4,500' on a local flight today. This was with cowl flaps cracked open just a bit. a7f3570791dc9a798fe79be4b9ff1e08.jpg

Fly Safe,
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6 hours ago, irishpilot said:

We checked the baffles and ensured no folding in the wrong direction. Temps are a little better, but oil temp and #2/3 cylinders are running hotter than I'd like. This is what I was running today at 4,500' on a local flight today. This was with cowl flaps cracked open just a bit. a7f3570791dc9a798fe79be4b9ff1e08.jpg

Fly Safe,
Safety Forum Mod
 

At 4500 in the summer in Texas I keep my cowl flaps full open.

At the cruise speed of the Bravo I don’t like low altitudes - too much speed at high traffic altitudes with airplanes that sometimes don’t have transponders. If I’m going any distance I’m above 10,000, usually in the mid-teens. Turbo charged Mooney’s like it much better above 10,000 and it’s much cooler.

On another note your volts seem a little low at 27.6.

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Maybe you already answered this question, but how many hours on the engine?  From what I’ve heard, low time engines tend to run a little hotter.

also, are the baffles original? I just changed mine to @GEE-BEE and I’m seeing a good improvement already (I’ll post later this week after I fly high to see how many degrees I’ve dropped in the high teens).  Guy told me yesterday that even a 1 inch gap somewhere will cause 40 degree higher temps. See below for a before picture of one of mine.

0ECCD24A-27A6-4A4B-844D-A7035A205A1D.jpeg

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Quick question for the others on this thread - my oil temp is consistently 190 or below on flights below 10k.  Yesterday, I was at 17.5 and my temp  crept up just above 200.  I know with the turbo working and higher altitude it should go up a little but was hoping to see if others have seen the same at higher altitudes.

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Quick question for the others on this thread - my oil temp is consistently 190 or below on flights below 10k.  Yesterday, I was at 17.5 and my temp  crept up just above 200.  I know with the turbo working and higher altitude it should go up a little but was hoping to see if others have seen the same at higher altitudes.
what power setting are you running?

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I'm going to go high on Friday and will be watching my temps closely. My baffles are orange and in better shape than the ones pictured. I'm looking forward to seeing your GEE-BEE results.

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So I went to FL150 and didn't see much change. I can't run 50 ROP as my #2 CHTs hover just above 400. I've got to run between 75-100 ROP, which puts TIT around 1520-1550 and the CHTs just under 400. FF is around 18.5-18.9 gph. This is with both 29/2400 and 30/2400 power settings.

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29/2400 for me.  When you say you didn't see much of a change was the temp still 203 or slightly above?
if I ran it at 59 ROP, then 402-405 CHT. If I ran 75-100 ROP and trailing cowl flaps a crack, they stayed at 392-395.

When I descended, I set 28/2400 and saw 370 CHT with lower oil temps as well. Here's a screenshot. I'm surprised one inch of Mp is making that much of a difference.19f89de0f9a14a33d4d7da79fac63177.jpg

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