Bravo Engine Longevity Poll

[alextstone]

Hi All Bravo owners....I am interested to know how long you (or a previous owner) have run your Bravo's engine before overhaul.  Thanks in advance for participating in the poll...

[Boilermonkey]

Ran to 2350.  Was still ok, but it was getting tired.  Starting was difficult, hot starts we crazy tough.  Even with gaped and cleaned spark pugs, cleaned fuel system, and retimed mags...she was getting tired.   Ordered a reman from the factory and the new engine is so very nice :-)

[rbp]

Still on engine #1. 1998

[Fritz1]

I am the 3rd owner of the aircraft, 2nd owner put in factory reman engine at 1100h, current engine is 12 years old and has 750h now and appears to be running fine, fly 120-150h per year, leak test mid 70s, run 2300/30", 115dF rich, max TIT 1600, max CHT400, hottest EGT 1500, change oil every 25h, ShellW100Plus, preheat below 50F, only unscheduled maintenance so far is TIT probe two years ago and waste gate control actuator right now which started leaking from the shaft seal a couple of weeks ago, replacement should show up on Monday, check exhaust valves with bore scope every oil change, plan wobble test on valves at next annual, cautiously optimistic that engine will make TBO, maybe will need a cylinder or two overhauled in between, really curious what the service record of other Bravo engines looks like

[LANCECASPER]

1 hour ago, Fritz1 said:

I am the 3rd owner of the aircraft, 2nd owner put in factory reman engine at 1100h, current engine is 12 years old and has 750h now and appears to be running fine, fly 120-150h per year, leak test mid 70s, run 2300/30", 115dF rich, max TIT 1600, max CHT400, hottest EGT 1500, change oil every 25h, ShellW100Plus, preheat below 50F, only unscheduled maintenance so far is TIT probe two years ago and waste gate control actuator right now which started leaking from the shaft seal a couple of weeks ago, replacement should show up on Monday, check exhaust valves with bore scope every oil change, plan wobble test on valves at next annual, cautiously optimistic that engine will make TBO, maybe will need a cylinder or two overhauled in between, really curious what the service record of other Bravo engines looks like

You could get your CHTs down at least 20 degrees with GeeBee die-cut baffle seals. In flight yours are "lazy" and are letting the air escape over the top and out the back instead of forcing it down over the cooling fins of the cylinders. With the power settings you are using and the TIT 1600 and lower you should never see over 380 CHT with GeeBee baffle seals for this engine and most of the time they should be 350-370.

His seals are pre-cut to the same size as the factory seals - not even comparable to trying to do it with a roll of material. Since yours still has the originals if you start at the pilots side front (cylinder #2) and work counter clockwise piece by piece (don't make the mistake of taking all of them off before you begin), you can do it in a few hours. There is no $400 investment that will extend the life of your cylinders more-so than this. Guy Ginbey's number is 800-556-3160. I've done it on a Mooney Encore and a Mooney Bravo and had great results.

[Fritz1]

ok, sold on the GeeBee seals, I have a 3'x3' sheet of the original black fabric based seal material and have made some replacement pieces but the silicone material is probably more pliable and I have a bunch of tired pieces in there

[Schllc]

9 hours ago, Fritz1 said:

ok, sold on the GeeBee seals, I have a 3'x3' sheet of the original black fabric based seal material and have made some replacement pieces but the silicone material is probably more pliable and I have a bunch of tired pieces in there

Drilling out the old rivets is the most tedious part of this process.  Two people, one with a shop vac and one on the drill makes it much easier.
Take one piece of baffling out at a time, lay the old and new on top of one another to align and punch the first hole in the new baffle, keep the old baffle on top and put an unpunched rivet in the first hole to align them. Then punch each hole and immediately put a rivet in each one, like cleco’s, working your way to the end.
By the time you get to the end of the baffle this will keep the rivet pattern and when you mount the new baffle it will be perfectly aligned with all the holes in the aluminum parts of the baffles. 
 

[Danb]

Have done the baffles on your acclaim

 

[alextstone]

 My engine has approximately 1650 hrs SMOH and it has had the cylinders replaced within the last 300 hrs as well as overhauled Turbo and wastegate, engine driven fuel pump, prop governor, mags (of course).  I fabricated new baffles a while back from the thicker, stiffer silicone material.  

[LANCECASPER]

1 hour ago, alextstone said:

 My engine has approximately 1650 hrs SMOH and it has had the cylinders replaced within the last 300 hrs as well as overhauled Turbo and wastegate, engine driven fuel pump, prop governor, mags (of course).  I fabricated new baffles a while back from the thicker, stiffer silicone material.  

With all that you've done recently I would feel very comfortable running this engine on condition. Very unlikely that a well-maintained engine just stops, it usually speaks to you long before. I know this is controversial on here, but with  oil analysis at your 25 hour oil changes you should be able see any trends. With relatively new cylinders, that you'll be running cooler than the last owner did,  it should be cost effective to run this one well past TBO and then exchange for a re-man. 

[alextstone]

7 minutes ago, LANCECASPER said:

With all that you've done recently I would feel very comfortable running this engine on condition. Very unlikely that a well-maintained engine just stops, it usually speaks to you long before. I know this is controversial on here, but with  oil analysis at your 25 hour oil changes you should be able see any trends. With relatively new cylinders, that you'll be running cooler than the last owner did,  it should be cost effective to run this one well past TBO and then exchange for a re-man. 

I agree and that's my plan.  

[Schllc]

On 4/15/2023 at 7:10 AM, alextstone said:

 My engine has approximately 1650 hrs SMOH and it has had the cylinders replaced within the last 300 hrs as well as overhauled Turbo and wastegate, engine driven fuel pump, prop governor, mags (of course).  I fabricated new baffles a while back from the thicker, stiffer silicone material.  

The other geebee guy used to strenuously make a point that using too thick a material will wear a hole in your cowling. 
I was dubious of this,  but the top section of one of my ovations did wear through the paint on the inside within 20hours of the new baffling. I had the old black rubber and I changed it for the red silicone. I changed that section out to the next thinner thickness out of precaution. 
I would  make sure you keep an eye on those areas to see if chaffing is a problem. 

[Schllc]

On 4/15/2023 at 6:54 AM, Danb said:

Have done the baffles on your acclaim

 

I did the entire engine of both of my ovations, only had to do a few pieces on the acclaims over the years. 

[cdikd]

still on engine #1. 1992

1750 h

[slowflyin]

Ran almost 2300 and she was still running strong.  A quart every 4 to 5 hours.   I only rebuilt because the timing was right financially.  

[FoxMike]

I overhauled the engine is two steps.  Soon after I bought my Bravo I got a call from Lycoming saying the engine was subject to a new AD requiring a new crankshaft.  Lycoming sent me a new crank and overhaul kit for $2K.  At the time I had about 300 total hours on the engine so I set aside the parts and flew until I had about 1200 on the engine and the age of the engine was 12 years.  At that point I had to overhaul to get my IA to sign the annual.  I had the shop do the bottom of the engine and most of the accessories and new hoses.  I had the cylinders honed and put the cylinders back on.  Flew the airplane till I got over 2K on the engine.  I decided to order new cylinders and waited more than 6 months for Lycoming to deliver them.  The original cylinders were still doing ok and I was thinking that I should have overhauled them.  Anyhow with just over 2200 on the engine I put the new cylinders and sold the originals to someone who overhauled them and I guess is still flying them.  

I think if you fly often and use reasonable power settings TIO 540 AF1B will go close to 2500 without concern.  If you push hard or do not fly often you had better think of an overhaul not long past the 2000 mark.  The biggest problem with this engine is the exhaust system.  Poor design in my opinion.