Due to family changes and changing career, etc I haven't flown much in the past two years. By checking my logbook, it was a total of 9.6 last year and less the year before in my plane, a few hours in other planes. Now that things are settling down, I want to start putting in 10 hours a week or more when the weather allows.

My plane is a C-170A on 29" Air Hawks with an O-300 that has about 550 hours on it. It is parked in Wasilla, AK.

Here are my questions:

1) I have a mechanic doing the annual tomorrow and the next day. I have read the opinions here of Phillips vs AeroShell and under his advice I am going to switch from Phillips to AeroShell. I have disclosed to him my lack of flying and he says he will make sure he goes through it well. Are there any areas in particular that I should be watching for as I am flying it after it's done? I intend to fly some pattern work for a few hours before getting away from the airport but is there anything else I need to be aware of?

2) I hear about guys that leave their planes sit that get corrosion on the crank, etc. Do they scope the motor or how do they find the corrosion? When I purchased the plane back in 2011 it had sat for about 9-12 months and I talked with several mechanics about scoping it for corrosion and every one of them said it wasn't necessary. Since purchase, I have put about 150 hours on it. In that time I have had a cylinder come loose in flight (we later determined that the bolts were not torqued to spec), but no other issues with it.

Thanks in advance.

I respectfully disagree with your mechanic concerning oil switch. For sitting or seldom flown airplanes Exxon Elite or Phillips are my choice. If flown often any of the 3 would do so why not use Exxon Elite or Phillips just in case you can't fly as often as you would like. I know I know, this wasn't a question about oil brands, sorry ....

Kurt

Ok, well, maybe I do have something to add....

In addition to all the obvious stuff, check;

Mud Daubers and bugs! Check fuel vent system for them.
Mice and mouse poop/piss in airplane including wings.
Bird nest in muffler if tail pipe was not covered.
Grease wheel bearings and tailwheel good.

Kurt

I agree on staying with Philips and especially agree on checking really closely for mouse poop/pee. Mouse pee will destroy an airframe quickly.

I looked behind the baggage bulkhead and behind the instruments and didn't see anything. Pulled up carpets and side panels too. Good to go on mouse droppings as far as I can tell. Mechanic will be looking in the wings anyway. Any sure-fire way to tell on corrosion inside the motor? Surely these guys are not scoping at every annual are they?

I don't have anything to add except I've been happy with Phillips oil for the last 5 years I've owned my 170. I was wondering where you went, glad to see you back!

For sure stay with the X/C.

907Pilot wrote:I looked behind the baggage bulkhead and behind the instruments and didn't see anything. Pulled up carpets and side panels too. Good to go on mouse droppings as far as I can tell. Mechanic will be looking in the wings anyway. Any sure-fire way to tell on corrosion inside the motor? Surely these guys are not scoping at every annual are they?

For some reason, that's not where mice seem to build their houses.....they're often in the wings. Look REALLY good in the wings, use a bore scope to help.

As to oils, any good quality oil is fine. I like Exxon Elite. But, whatever oil you use, add Cam Guard to the oil.

I'd start an oil analysis program, and run that for the next couple years. You can buy the test kits on line or at Stoddards, and mail them in with the oil samples. That should show any issues that may arise.

Other than that, trust your mechanic, and fly the hell out of it.

MTV

So happy to be back to having a schedule that allows for flying. I moved into a career in real estate so not only can I work my schedule but I can from time to time use my plane for work. Nice since its parked in my back yard half the year until I get my floats and then can be all year.

Why / how would mice be in the wings? I've got to imagine that they're eating wiring? Won't a couple of hours with the nav lights and landing lights energized would be a telltale in the unlikely event that they went there instead of eating carpet and insulation?

I'm always pleased when a wayward pilot rejoins the fold!

Phillips plus Camguard. Add my vote to that side. Especially with Continental starter drives. It may not be necessary, but it might help.

What others have said. The spark plugs will be out at annual, so a quick check with a bore scope should be easy and cheap. I wouldn't expect any corrosion in the cold Alaska climate, but that's offset by your proximity to the ocean. If a jug has come loose in the past, it can't hurt to check the torque on the cylinder studs and through bolts. Check the easy ones, and only pull baffles to check the rest if you find the accessible ones loose.

After annual, fly it 10-15 hours, then ask your mechanic to give it another once over. Recheck cables, pulleys, plugs and oil analysis. A repeat compression check wouldn't hurt. After you've got everything moving again, a hidden problem may reveal itself. Four hours labour? Same as a full tank of gas.

The very little bit of flying you did was better than nothing, and you should be OK.

Yup Phillips to aero shell?? You're doing it backwards!

907Pilot wrote:Any sure-fire way to tell on corrosion inside the motor? Surely these guys are not scoping at every annual are they?

Borescoping is not standard practice for an Annual inspection.
A borescope can help but there is no way to tell 100%.
Check the cylinder bores with a bend a light and a borescope. Sometimes it is easier to get a look at some things without the borescope. Other times there is no possible way to see without a borescope.
Also a good indicator is to pull the mags and check the impulse couplings. They seem to rust first.

If everything seems fine then run it for a while and check often for metal.
Sometimes problems take a few hours to show up.

Try not to fly over "Hostile Terrain" for a while to minimize any risk.

[quote="907Pilot"]Why / how would mice be in the wings? I've got to imagine that they're eating wiring? Won't a couple of hours with the nav lights and landing lights energized would be a telltale in the unlikely event that they went there instead of eating carpet and insulation?[/quote

I have no idea how the little bastards get into wings.....it's a hell of a hike for them. Nevertheless, that's where they often wind up. Good news is in your part of the world, they're mostly voles, not mice, and voles don't seem to be as enamored with airplanes.

They're not getting into airplanes to eat anything. It's shelter they're after. Yes, they chew on stuff, probably as much in search of nest materials as anything, but they're not eating carpet.....

Look in the wings. Trust me, a mouse house in a wing can create a lot of corrosion. Long ways to the outhouse, and the little buggers just pee in your wing.

MTV

update: had the mechanic go through it and flew 1.3. Only issue that came up is that now my left tank gas indicator is stuck on empty. Odd because it has always been accurate and it's a mechanical gauge but I guess now I just pay a little bit more attention to my burn while I am flying.

Gauges are only required to read accurate when empty so, you're good

The cork probably went bad and sank. Not hard to fix.

Update #2:

Replaced the float in the tank, it cost about 3 bucks and now it works even better than before. 170 owners should look into this if your gauge isn't perfectly accurate. Now it is.

On the down side, compression tests showed between 6 and 12 psi on one cylinder, so took it off and sent it to the shop. Bad rings and a small amount of rust on the inside did me in. Getting new rings and should be good as new. I guess I need to fly the tar out of my bird to prevent this in the future.

12psi on a compression check from bad rings and a little rust?.
Maybe if each ring was busted and bits missing.
I've never heard of a cylinder ever being that low. You sure he checked it right?

I'd be skeptical myself but had problems with this cylinder last year as well. Low readings first two checks then did a run up and checked again and got 68.

I was in attendance when an annual was being done on an old C182 that had sat for several years. Compresion on all 6 was abysmal- 20 maybe? Fired it up and taxi'd around the airport for a bit, then checked it again & they were all in the 60's. I was amazed!

I agree, run it a bit and see if the compressions move upwards. Due to various moves around the world my 172 sometimes sat for many years unflown. Went to Okinawa and then to Germany for 7+ years. Left the plane in Az. and with its nice dry climate, the plane underwent an annual with the only issues being Bat crap on the top of the plane. That stuff hardens into a concrete like substance!!! After the annual I flew it a few hours in Az. and then headed to Georgia and from there up to MN. Its been flying great since. Actually did my BFR a few days ago in the old bird.
Long inactivity, while not the best scenario, isn't bad as long as it was stored correctly.