Map

[Rynoth]

On page 46 of the turbo manual (http://www.aeroconversions.com/support/ ... Manual.pdf), step #8, it describes setting up the wastegate actuator as follows:

"Adjust the actuator's pushrod so it JUST holds the wastegate in the closed position, but also has no end play."

I take this to mean just enough pre-load to fully press the wastegate closed and take up all slack between the wastegate and the spring, without actually compressing the spring.

[wlarson861]

Ok so for my bad. I didn't get a stop nut for the waste gate actuator in my kit. I thought that since the end was captured at the waste gate end the stop nut was unneeded. I was wrong. I put the stop nut on the actuator and the engine performed as advertised. I feel stupid at this point but will continue to test the turbo further. I don't understand how the actuator really works but this seems to have worked for now. I had to go back to the manual to see the jamb nut and then go buy one from the local hardware store. By the way its a 6mm by .75 metric nut. I didn't realize that the shaft of the actuator could turn when the engine was in flight. I'll try to fly more to confirm my fix is complete. Today's flight was a blast going out at 40'in of MAPin climb and cruising at 30.9 and seeing around 140 mph true

[Rynoth]

I don't understand how the actuator really works but this seems to have worked for now.

Basically, there's a plunger with spring pressure on one side, and manifold air pressure on the other side (via the line connected directly to the compressor side of the turbo.) When manifold pressure reaches a certain point (~44psi), it overcomes the pressure of the spring and the plunger gets depressed, opening the wastegate via the actuator arm. This also happens to be why excessively pre-loading the spring will actually raise the manifold pressure required for the actuator to engage (more spring pressure = more manifold pressure required to move the plunger,) therefore more maximum boost pressure and less safety margin.

I imagine that the plunger itself can rotate within the housing, which is how the actuator arm rotated during flight without a lock nut. Seems like a smoking gun, I bet you've solved it!

[wlarson861]

Another test flight today and it performed as advertised.

[MichaelFarley56]

By the way Bill, I went ahead and installed a 'vent grate' in my cowling above the turbo, to let heat out after landing….. works good and no ill effects during flight.

Do you by chance have a picture of this Geary? I'm interested in what you've done. I haven't had any ill effects on mine but the cowling does get pretty warm on shut down on my engine.

Also, how do you like the VG's on your airplane? Any noticeable effects?

[wlarson861]

I really love this conversion now that I figured out the details. I was getting the low power benefits but now I get the high power stuff too. Now all we need is for Sonex to come out with a retro fit auxiliary fuel tank so we can go 3.5 hours with 45 min. reserve. I want to go places now that I can go fast!!!! Hope to get to Crossville this year since I have not made it since 2012.

[marsolgp]

Mike, I've sent you a PM to answer your question and attached a couple photos of the vents. I still haven't had any luck posting photos here, so feel free to repost photos if anyone else is interested.

[Brett]

Now all we need is for Sonex to come out with a retro fit auxiliary fuel tank so we can go 3.5 hours with 45 min. reserve. I want to go places now that I can go fast!!!!

That would be great to have a factory approved additional sub tank. Even if limited to one passenger for those long treks.

[MichaelFarley56]

If anyone wants to see Geary's new cowling vents, here are a few pics. This is a great idea and I will probably be doing the same thing here soon!

[marsolgp]

Thanks Mike for posting pictures….. for anyone curious, the vent on the LH cowl is over my MGL RDAC. This was actually my main reason for the vents, the RDAC would give me some crazy CHT reading (700 + degrees F), on the ground only, after the compartment got heat soaked. This has solved that issue and has got to be beneficial for other electrical components that are 'trapped' in this oven after shutdown (ignition coils and triggers especially).