Looking for a shop that has good turbo experience

[skyfarer]

Can anyone recommend a shop in the midwest that is familiar with our Bravo turbo setups? Mine has an issue that I need looked at. As I increase the throttle, normally the turbo would kick in smoothly at around 27" or so. But recently it hangs at 27 even as I'm twisting the throttle higher. It eventually kicks in all the sudden to red line and then comes back. At that point I can smoothly push the throttle in and MP follows normally to red line.  I replaced the waste gate last year when I discovered that it was leaking oil. I see some oil around one of the controllers (I'm not sure if it's the density or the differential one) so I think one or both of these could use a cleaning/inspection/test. I'd really like the whole system checked over and properly rigged by someone with experience on these systems.

Thanks!

Jeremy

[skyfarer]

I should add that I'm on Don Maxwell's schedule to deliver it to his shop last week of February for it's annual. So I'm trying to decide if I get the turbo system looked at now or just wait for Don to look at it.

[Rick Junkin]

@skyfarer There are two MSCs near us (I'm in Gatlinburg TN). Cole Aviation (706) 271-0222 at KDNN in Dalton Georgia and AGL Aviation (828) 391-8645 at KMRN in Morganton NC. You might give them both a call and see what they have to say about fitting your need. 

AGL has changed ownership since my last annual there but I've heard good things about the new owner. Lynn Mace, the previous owner, is a solid guy and now works at Maxwell's.

Cole Aviation has a good rep but I don't know how versed they are with our Bravo turbo system.

Both are within an hour and a half of Louisville by Mooney.

[Fritz1]

Don is probably your best bet, end of Feb is just around the corner, to work correctly the controllers need about 180 dF oil temp, are you sure it is not just the gauge that is erratic? my density controller was not kicking in enough boost at high IAT and overboosting at low IAT, instead of trying to fix it I installed an IAT probe that feeds to the EDM700. There is a table in the service manual, typically you want at least 35" at low temp and at the most 37" at high ambient temp, the IAT probe is easy to install, intake plenum has a thread for it, with that probe you can fine tune takeoff power boost, I have never seen boost over 37" in my engine though, that is how I have set my density controller after a fair amount of tweaking

[skyfarer]

@Fritz1  I think you’re on to something here because this problem has become worse as it’s become colder here. I think I remember this happening last winter, sporadically. Then the problem disappeared in the summer. Yesterday it was the coldest I’ve flown, -4C on the ground. The engine oil was about 40F, and the cylinders about 40F too before I rolled her out to start. I didn’t run up until the oil hit the green arc, 100F. The POH say 75F min oil temp for run up and 100F for take off.  Looks like Lycoming says 165F minimum is ideal.

Anybody else fly the Bravo in really cold weather and have some tips or similar experiences?

 

[Z W]

Lubricating automatic wastegates with Mouse Milk seems to prevent or fix many issues with erratic boost. No experience with your engine but mine gets lubricated at every oil change and annual.

[LANCECASPER]

14 hours ago, skyfarer said:

@Fritz1  I think you’re on to something here because this problem has become worse as it’s become colder here. I think I remember this happening last winter, sporadically. Then the problem disappeared in the summer. Yesterday it was the coldest I’ve flown, -4C on the ground. The engine oil was about 40F, and the cylinders about 40F too before I rolled her out to start. I didn’t run up until the oil hit the green arc, 100F. The POH say 75F min oil temp for run up and 100F for take off.  Looks like Lycoming says 165F minimum is ideal.

Anybody else fly the Bravo in really cold weather and have some tips or similar experiences?

 

What weight of oil are you running?

[PilotX]

From recent experience you will know when the turbo stops turbroing. Need to lube mine as well.

[Fritz1]

second the mouse milk, causes reproductive harm in California though, preheating helps a lot, Reiff heater gets engine to 120 dF, running 1500W cabin heater in hangar prevents windows from freezing over during taxi, Phillips XC 20W50 appears to do well in the Bravo engine

[Fly Boomer]

Great picture.  I'm saving that one.

[skyfarer]

On 1/17/2025 at 8:50 AM, LANCECASPER said:

What weight of oil are you running?

Phillips X/C 20w50