Update on N680RR

[Willis]

So, its ONLY the AC that's kaput?

Pressurization is okay?

which AC unit do you have?

[ghancock]

No, the AC was working perfectly, no flux in pressure gauge.  Then I turned on pressurization and it started working for a couple minutes and then the entire system quit.  Now the air conditioning won't work at all.

I'm also wondering if anyone can tell me if the RAM air should be blowing air into the overhead vents?  When I put the system on RAM air you have hardly anything at all flowing through the vents.  Starting to wonder if I have a broke hose or something but make that is normal.

Thanks,

Glenn

[ghancock]

I uploaded a few more pictures from our trip to Indiana and back today.  I have some videos I'll be posting later.  The pics of the top of the nacelles shows how far back the exhaust blows with and without the exhaust deflectors on.  Problem is I've placed 1 on the left engine thinking they'd be a better side by side comparison but I need to reroute the oil breather tube first because it just messes with the results.

The plane did awesome but the right engine seems to be leaking about 4 quarts of oil compared to 2 in the left for an 8 hour flight.  Most seems to be coming from the breather tube but not sure why it is blowing so much out.  Will do more research on this.

Family is now totally in love with the airplane though and I have a big problem with the air conditioning system that I have 2 days to figure out before the 310 becomes our plane for the Caribbean trip.  Hopefully will figure it out but right now I get zero air blowing into the cabin from RAM to Flight Auto, nothing...

Will let you know when I get some videos posted.

Glenn

[Willis]

Easy checks first.  (assuming the compressions are all good, and thus the rings are good)

Any entrance to the crankcase for air, pressurized from below OR above, will pressurize the crankcase and blow oil mist out like there's no tomorrow.

1.  Make sure the oil fill cap has a new gasket.  (i presume you have a dry sump.  Check the return tank.

2.  check the gaskets at each pushrod tube, both ends.  Normally this wouldnt be a source, but with the reverse flow air cooling from below, the lower deck see higher pressure than the upper deck.

3. breather at the reduction bearbox, accessory gearbox  and the prop forward seal.  All of these can lead to pressurizing the case.

just some ideas.

B

[ghancock]

Thanks, I do know the oil filler cap needs new o-ring as it leaks a little bit.  Also, pressurization problem ended up being a scat tube that blew off from the turbine.  It is fixed and she's back on the slate for taking to the Caribbean on Sunday.

As for the oil blowing problem, yes, all cylinders have good compression and no oil leaking from anywhere but the breather tube.  Will continue to look into it as I blew out 4 quarts in 8 hours of flying from the right engine and 2 quarts from the left engine.

Glenn

[Willis]

if thats the only problem, then consider an Air/Oil separator.  Could save you the headache.

[Adam Frisch]

Glenn, I could remember wrong, but isn't it because the crankcase pressurizes that oil goes overboard via breather tube? It shouldn't pressurize, but I can't remember right now what causes this. But a mechanic would know.

[Steve binnette]

Not sure if you have a wet vacuum pump but those will send a lot of oil overboard. If they fail.

[ghancock]

Adam, yes, generally that would be the primary reason and usual pressurizes past the rings if you had a bad ring somewhere.  My only issue is having both engines doing the same thing seems to make it common but guess I could have 2 engines doing the same thing.  I also figured out the blower problem and ended up being a hose that blew off.

Only issue now is a huge flux in hydraulic pressure when I put system into flight auto.  Still no leaks though of skydrol so happy about that.

I hope I can have a good safe flight through Caribbean for the next couple weeks as the plane is turning a lot of heads.  Really cool to be able to bring her along for such an awesome trip.  Family is loving riding along in it.

Glenn

[donv]

Glenn, you'll need to make some posts in the "Commander Travels" section when you get back! I'm interested in learning about places to go in the Caribbean!