for... Skyking...

[Don Hickman]

Guys, I can't keep up with this board from down here in the Carribean!

But to answer Skyking's question, I fly from Bedford, IN (BFR) to New Orleans (NEW) and refuel. Takes about 03:30. Then from New Orleans direct to Cancun (MMUN) and that takes another 03:30. Groundspeed is usually right at 170 knots running 57% power at FL 180 or 190.

Now it's back to the beach!

[skymaster]

Howdy: The turbo filter works. The former owner designed a filter and recd caa 337. approaching 350 hours unmarked by crud. We fly 50 hrs between oil change. Exhaust leaks are another topic. I have sent the data and field approvals to GMAS. Hope it helps . James Henderson

[Don Hickman]

All right! Let's get one of those turbo filters! I just got back from Mexico. Stupid turbo wouldn't boost on the front engine at take off from my unpaved 2,000 foot strip. 30" was all I could get and, given the temps and load, I just did make it over the wall. But by the time I landed at Houston it had cured itself. Full power on takeoff when I no longer needed it!

So, if there's a filter out there for that oil line, I want one! Make that two.

[SkyKing]

Don,

If you would, please describe what your front engine gauges were showing during the takeoff roll from brake release at your unpaved strip, e.g., MP, RPM, fuel flow, oil press & temp. Any anomalies during the run-up, or normal? Did you get any turbo boost at all? Or, did it start coming up slowly during the takeoff roll, or after liftoff? And what about during climb and cruise?

What mine has typically done is come up to about 25-27" and just sits there at brake release, at full throttle, with the out-of-synch wow-wow between the front and rear. Then I get a slow turbo spool up to about 35" and 125-130PPH during the takeoff run. If I land somewhere and then restart and takeoff within say 30-minutes or an hour, I usually don't get any boost at all until after liftoff and in the climb, so I've been reluctant to go into any unimproved short strips.

The manuals say that if everything is rigged properly, you should have full-turbo boost with 2/23 throttle, which is the way things used to work and my rear engine always does, but we're pushing the front throttle all the way forward even to get the 25-27" prior to brake release. Leaving it at full throttle position, it eventually comes up to 35". The engines ususally get synched up and the wow-wow disappears just before liftoff. We've checked the rigging and everything seems fine.

Once into the climb or cruise, everything seems to work just like it's suppose to, i.e., normal throttle positions for a given MP, but the front reacts slight slower than the rear engine. Oil pressure is top green and temps at least 100F prior to takeoff. And normal cyl head temps. Normal indications during climbs and cruise. And I recall one day in cruise at 8,000' running the RPM's up to 2800 redline and bringing the throttles up and no problem acquiring 37" with full-rich mix. And as I noted in a previous post, the other day while at 17,500', noticed that when I pushed the front throttle up from 30" to full at 2400RPM, the MP wanted to oscillate between 33 and 38" like it was bootstrapping... but steady at 30" or 33" with 2400. I should have upped the RPM to see if it would have stabilized, but neglected to do so.

Do you have any of these kind of MP fluctuations at altitude, or are things rock steady?

Got to be some pesky carbon/grime in the system somewhere. Maybe it's the controller instead of the wastegate, as things work normally once airborne.

Be interested in your indications, throttle positions, MP's and RPM's. BTW, my front engine is at 1250 TTSN, and the rear at 150 SFRM. I'll have to check the logs, but it seems the front controller, and wastegate were overhauled a couple of years before I acquired the plane (and probably needlessly!), and I think the front turbo was replaced at 700 hours, but I'll have to check to make sure.

SkyKing

[Don Hickman]

Sky,

On takeoff Friday morning from the unpaved strip on the island the MP on the front engine only came up to 30" and never exceeded that. The rear ran up to redline and then backed off to 37" which is what it always does. So does the front when the turbo is working. MP dropped on the front as I climbed out but would hold at 27" at FL 180 with full throttle. Fuel flow during takeoff was 104 on the front, 140 on the rear.

Oil temps were above 100 at takeoff (heck, the ambient air was at 95!). I can't remember what the RPM was but it was above 2500 as I remember pulling it back to 2500 along with the rear.

While in cruise the MP would slowly cycle up and down by about 3" and the wow-wow would come and go. It's just impossible to keep the engines in sync. The rear would hold rock steady at 27" but the RPM would fluctuate which just drives me crazy.

When later taking off from Houston Hobby the front spooled up to redline, then past redline and pegged! I had to pull the throttle back to get it below redline then pushed the throttle full forward again and it held at 37" during takeoff. However, while in cruise it still runs up and down by about 3".

So tomorrow I'll be having another conversation with my mechanic but I assume that whatever piece of dirt or carbon that had plugged it up in Mexico worked it's way out by the time I was leaving Houston so there's probably nothing for the mechanic to do. But I don't understand why it blew completely past redline nor what is causing the up and down in MP while in cruise. And 27" is the maximum I can get out of it above 17,000. The turbo is brand new as the old one burned up during an unexpected engine shutdown during a missed approach two months ago and I've installed a new controller as well. But nothing has changed regarding performance even with the new equipment. Sometimes it works and sometimes it doesn't and it never holds steady no matter what.

I'm about 150 hours past TBO on the front engine and even though it's got good compression and isn't making metal I'm beginning to think I should just scrap it and put in a new one. I'm about out of ideas on how to fix the front turbo problem. And I have no idea why the rear prop won't hold a steady RPM. That engine still has 300 hours to go before TBO and everything works ok except for the RPM fluctuation. At least it gives me something to do while flying long legs across the Gulf of Mexico!

[Mark Hislop]

SkyKing:

I wonder if your problem isn't related to the prop governor, rather than the turbo controller. The disonnance you hear is related to engine speed. I can vary my MP quite a bit, and still keep the props in sync (although I've never tried it at takeoff). I'm not sure this fits all of the other symptoms you've described, but it might be worth looking at.

Mark

[GMAs]

Skyking is right... its not the trubo system... as it only controls the MP... RPM after 1800 is controlled by the prop govnr.... you might want to pull it and have it checked... bet you will find the little screen up at the inlet is kinda full of stuff too... as its a real fine stanless steel screen and it traps parts of the carbon so it doesn't go into the gov gears which increase the oil pressure to the prop piston which cause it to pitch... also if you have sagging oil pressure you might want to check with a master gauge...sometime s on the high time engines the galley way fills up with crud too... if the oil is not changed frequently... smile...

As to Skykings problem... you need to cap off the accuator and check for full operation... and no you can not fly it that way.... but, I would bet your problem is either with the accuator or controller...

And it does no good to clean out the accuator if you don't clean out the lines.. too... after all their is more of that stuff just waiting at the bottom of the accessory case lined up to hit the road thru the tunnel of the lines right back into the accuator... but, if in fact its not the accuator.. sorry .. your going to have to pull the controller and send it in ...

Now just for your info.. yes you can cap off the accuator.. and it will give you full turbo boost... and yes you can take off with it.. but, its called manual override.. and if you are not on the stick ... so to speek you can bend rods.. and do all kinds of nasty stuff to your engine... but, in a emergency...you can have the power if you need it.. and don't have a way to clean/clear the accuator... but, we don't recomend it... as others do.. because the system should work right all of the time or else don't fly... kinda thing...


As to the accessory screen/filters... seems that someone is going to have to make them.. as we are not able to get anyone around here that even wants to touch something that says Airplane on it.... James Hinderson sent me the drawings.. and that becomes another problem.. they seem to think that it might be infringment... gee... what next...

Skyking also has a set of the drawings... but, James if the guy who made them up might want to also make them up... I would like to hear from him... could you please ask... as it seems that the FAA is starting to come around and after many hours of talking they are saying good things... I gave them the old what ya going to do if it fails on take off.. with out it... then are you going to be responsible... and they shrugged their shoulders and all said... well.... maybe you have something their... great but, then who is going to make it up... is next... and how much are they going to cost each...

Cessna didn't respond with anything... nor did Cont engine so time is up.. now we can proceed with plans to go the 337 route... for field approval... but, we need a test pilot... for the first one... smile..kinda thing...

I look at it this way... if you have the accuator clog up now.. it blocks the oil flow... so if the screen clogs up... what is the difference... but, the screen would allow more to be trapped before it does... still doesn't relieve you of the maintance problem of keeping the engine clean... but, we are also looking into a oil route change too.. which would not require the filters at all ... so we'll keep you posted... stand by for News... as they say.. may be a topic at the next yearly meeting for the skymasters.... smile... GMAs...

[GMAs]

I forgot to mention... take both of them off and have the checked... togeather.. that way they can set them both on the same mach... or else you will have the dreaded control offset... and they won't be togeather... smile... hope this helps GMAs

[Bob Cook]

Don , Skyking

Investing 20 bucks on a can of AVBLEND is worth a shot!

This stuff came out of a patent some years ago called Lenkite. For some reason it breaks down carbon and you should see the results very quickly. I know the chemistry for this stuff!

Don, if it doesn't help I will buy you LUNCH the next time we are together (up to 20 bucks).

I do not believe in snake oil or UFO's and I believe that carbon on the backside of the pistons in older engines can create hell.

The front engine runs much cooler than the rear thus more prone to "crap" (carbon).

Skyking, same offer applies.

Bob

[Mark Hislop]

Bob:

If Avblend breaks down the carbon, does one run the chance of getting a slug of carbon right after use. I know this is can happen if an engine has had non-detergent oil, and suddenly changes to detergent oil. Or does Avblend dissolve the carbon?

Mark

[Bob Cook]

Mark

It appears to dissolve the carbon as opposed to "cleaning it in chunks".

It is very expensive for what it is but it does the trick.

BTW there is a real good article

http://www.avweb.com/articles/pelperch/pelp0059.html

worth reading.

bob

[SkyKing]

Sure would be nice if there was a way to respond after each message to that particular individual's comments... SO, sorting through all of this, here's my nickel (hope to keep this somewhat straight forward!):

First, DON: You may indeed have a governor problem if your rear engine won't keep steady with the front, or vice-versa... I do hope you run the friction knob up good and snug, as that does help to keep things steady. But I've noticed it kind of depends on the operating WX environment... I've had days when things just purr along beautifully without having to readjust the props.... and then there are those days when nothing wants to stay synched up. Wonder if when you've experienced the variations in MP if you tried selecting a higher RPM and/or boost pumps?

Second, GMAs & MARK: As to the dissonance (I assume the wow-wow-wow sound), I'm only hearing this occur during the very early part of the takeoff roll... in the climbout, and in cruise, we don't have any of that occurring, like Don is apparently experiencing. When we've experienced the MP/Fuel Flow gyrations, the governor's have held the engine RPM's very close, and again, I think this may be "bootstrapping"... and that's what we're looking into now. Next time out we'll try a higher RPM and see if that cures the MP gyration problem up in the teens. Oh, and no "sagging oil pressure"... all is top green and no oscillations-rock steady.

BTW, I was looking on the type certificate for the TSIO-360C/CB, and it lists "5 useable quarts" in the oil department. Last couple of flights we've used 5.5 and no belly scum... clean as a whistle!

Third, BOB: As to the AvBlend, it's probably good stuff and we might give that a whirl... but another product out there without the "A" word attached has done a magnificent job of cleaning out our front engine and lubricating the upper end... and would you believe it's only about a $1.99 a Quart (32-ounces) from Wal-Mart!!! It's called Rislone... and it's GOOD STUFF! AvBlend is $19.95 for 12-ounces and I see they recommend two-cans for a 6-Cyl engine. BTW, my rear engine runs cooler than the front.

The last oil filter change on the front showed almost no carbon... and before we started using it we saw the oil filter folds full of it and used to see little tiny carbon flecks attached to the leading edges of the white antennas on the belly in the exhaust slipstream... these days they only get coated with a very light tan color -minus the specks and flecks. So that's a good indication. We're changing the the oil & filters at 25-hours, but this last time we did the front engine at 20 hours.

Speaking of aircraft piston-engine oil... I'll bet if we knew the matching MIL number and specs of a good grade of automotive or diesel engine oil - in the same weight and viscosity as the aviation oil - I'm sure you'd find there's not a dime's worth of difference and your engine would run just as well. Of course, that's a well guarded secret by the oil companies. But YES, in that department, we continue to use the single-grade of AeroShell W100-50 year round.

Like a lot of things, the turbochargers are a standard automotive unit... but added to that is the "A" word (Aviation) and the God-like words, "PMA-FAA" approved. Yep, it's true... and a whole bunch of folks are capitalizing on this little deal. Look at your alternators... nothing much different except for the connection to the engine, at least on the TCM TSIO-360's.

Here's a clever trick the oil companies play on we pilots. Ever hear of the term "BRANDED aviation fuel"...? That's where the AvGas comes out of the same storage facility, but gets labeled AirBP, AVFuel, etc. Like up in Seattle, there's only ONE bulk plant for AvGas... it's the Equilon facility on Harbor Island. Equilon is really Shell. But when we get it at our local FBO, it's now "BRANDED" as AvFuel or AirBP. Cute, hey? So then, why the big variation in the end-user price??? Hhhmmm. Another little racket.

SkyKing

[Bob Cook]

Skyking

the "wowing" IMO is either governor or fuel flows may be a bit off. I would at least check them to make sure.
at higher alt I have put on boost to low and readjusted mixture. Seems to settle engine on hot humid days.

re oil. did you not know they "monitor" the oil going into the jugs?

changing oil every 25 hrs is a big +++. AV blend, rislone doesn't matter. Anything to get the carbon down to a managable level including super lean when idle or taxi.

Let's not get onto the FAA/PMA issue! That's a hornet's nest. I am not about to suggest, recommend, or mention anything that is not "approved". Did you read the article on AVWEB (above) ?

Bob

[skymaster]

hEY gmas: screen is from rv automatic transmission. its not a pma part and it came with my aircraft. the previous aircraft owner is pushing daisies. He thought it would be a good idea. James Henderson

[SkyKing]

Yes Bob...

I did read the Pelican Perch article on "Fried Valves"... twas a VERY good read. Thanks for the heads-up! I saved it to CD Rom for later re-reading. Good stuff.

No argument here... 25-hours on the oil is the way! Especially considering the former owner only flew the plane about a half- hour each month and the oil didn't get changed except at annual. And there were a couple of times it sat out-of-annual for two year runs, so that wasn't good either... at least he kept it hangared and in a dry-climate area during the non-use.

I'm sure the bird never experienced my 75% power climbs up into the teens, nor cyl-head temps approaching 380F, and this routine has obviously "unsludged' things.

And DON... NO!, I wouldn't do an overhaul as long as compressions and power are good to go. You've probably got a similar situation to mine... too much setting and sludging. So, change those filters and oil, run it lean and most importantly, make sure you heat the engine up, burn the moisture off the oil and get the gunk out. EXERCISE...EXERCISE...EXERCISE!!!

Mike Swanson is supposed to be up my way in the next couple of weeks and he tells me he's bringing the wastergate-controller "cleaner-outer" purging kit with him, so we'll make a parts list and share with the rest of you turbo operators.

As I'm writing this, just heard a radio commercial that Shell is coming back (the deal is, Shell/Equilon are taking over all the old Texaco outlets as part of the settlement thingee with the merger of Chevron/Texaco... Gee, I hope they bring us some "BRANDED" Shell AvGas too... Maybe we can get the price down below Two Bucks.

BTW Bob, I think I'll try a can of AvBlend and see what gives...

Skyking