Wastegate backflush kit

SkyKing · #1 07-07-02, 10:25 PM

Has anyone made up a backflush kit for cleaning out the wastegate actuator... especially the restrictor orifice on the inlet side of the TSIO-360C/CB's?

Sometime way back on Peter's old message board, GMAs referred to it a couple of times but I never did see a parts lists of components needed to do the job. This is a must-have item for those who have high-time turbocharged 360's because of the carbon buildup.

Cessna could have helped the situation by taking the oil from the other side of the filter, but the way things are set-up the inlet oil line for the wastegate comes off of the pump side before it goes into the filter, so all the dirt and crap makes it into that little orifice. Not a problem on new engines, but when they get older this becomes a major pain in the behind because any tiny carbon flecks generated from the oil squirts on the backside of the pistons are instant candidates for blockage of the actuator... especially if there's been infrequent use of the plane.

SkyKing

SkyKing · #2 07-08-02, 10:47 PM

Gosh... you mean that nobody with a turbocharged TCM TSIO-360C/CB engine has ever had to clean out the wastegate? Now I know that just can't be true!

SkyKing

GMAs · #3 07-10-02, 01:38 AM

I will take some pictures and show you what we use.... and give you a discription of the parts... that you will need... its really pretty simple... but, we are still waiting on the approval of the inline filters... for the engines... which would do away with the cleaning routine... smile GMAs

Bob Cook · #4 07-10-02, 08:30 AM

Skyking

I have NEVER had to clean out the wastegate... ever.....

Bob

SkyKing · #5 07-10-02, 03:39 PM

Gee Bob,

That's nice. I just don't get to fly almost everyday like you, and my front engine has about 1250 TTSN, and as you may recall, it sat a whole bunch with infrequent, short hops. We at least try to fly once a week for an hour or so, but due to my unemployment status and my suit for age discrimination against Horizon Airlines now in the Ninth Silly Circuit and minimized resources, my time to fly has been necessarily limited somewhat, whereas you're in a completely different status and use your airplane in your business and for routine pleasure. We all don't have an unlimited gas credit card. B-I-G DIFFERENCE! ~ But at least I don't have airplane payments.

But... you know what? My mechanic and I discovered something last night that made my blood boil and that might be at least a contributing factor to the slow turbo spool on my front engine, and the variations in cabin pressure we've seen at higher altitudes. Other than slow spool on takeoff, everything else was fine below 10,000'.

While carefully examining the almost hidden underside of the sonic venturi flow limiter where it connects to the 1-inch "Y" from the main induction tube with a rubber hose coupler and two clamps, it was observed that the clamp on the end of this 1-inch "Y" (the right side from the cockpit) was crushed inward and not making a seal. Upon removal and looking into the end of the opening of this short section of light-weight aluminum tubing, there was almost a complete inverted "^" look to it on the bottom side lip, and crushed inward almost half the diameter of the tube for about an inch back from the opening, and the rubber hose and clamp could in no way manage a seal. Whoever did this little trick should have had his hands burned.

Obviously, the 'former' shop that so-called 'maintained' this plane under the prior owner had a hamhocked-hamfisted mek-a-nick, or as is the case in most shops, not a mechanic but a young 'helper' putting things back together (no wonder you always see the wrong screws in the wrong holes!), apply too much pressure to the clamp and the flat side of the clamp being made of steel won the game. My mechanic and I worked with this little problem for almost two hours last night using some wood dowling and other tools to reform the "^" into a perfectly round opening and then reattached the sonic venturi flow limiter, the rubber hose couplers and fitted the clamps snugly, but not overly tight. We'll now test fly the airplane and see what indications we obtain. With the 'hole' now sealed off, things should be a whole lot better.

But back to the reason why I posted this thread in the first place. It is a KNOWN FACT... and GMAs has covered this many times on Peter's message board... when these TCM 360 turbocharged engines get up in time and years, coupled with infrequent use, short hops, etc., the condition DOES develop where the engine tends to carbon-up if not sludge-up, and this stuff DOES enter into the wastegate actuator and controller and CAN cause problems. Mike Swanson's P337 had the same identical thing going on with his... like mine... and it was NECESSARY to flush the wastegate actuator because small, hard carbon flecks WILL plug the orifice-restrictor at the inlet side, which is only about the size of .32 safety wire.

I'm glad to here that you have not been bothered with this headache... and hope you will only see BLUE SKIES!

SkyKing