Why not buy it

[eddyb123]

I'm looking to buy my first A/C and one I'm looking at has a crack in the tail cone noted in the logs, but nothing says it's been fixed. Also one cyllinder = 65/70 comp. These are the only things that are of concern. Opinions please.

[cgzro]

I'd recommend having an independent pre-purchase inspection that includes compression checks, looking at the oil screens etc. perhaps sending off an oil sample for analysys. Have a really good look for corrosion, or fabric condition/age. Count on a full day.

Its well worth spending $500 bucks up front to have an independent mechanic open it up, look everywhere and tell you what he thinks. Also while there may be things that are 'airworthy' now they may well require replacement shortly. For example hoses and rubber usually have to be changed regularly and that can be quite expensive. Props have limits as do mags etc. Always good to know not only that the plane is airworthy now, but what it will cost you in regular maintenance in the next few years.

Trust me money spent in pre-purcahse is never wasted because there are always problems and you can then haggle the price down a bit to recoup some of the costs of the inspection, or if you decide to walk away, that $500 will be cheap compared to the cost of buying a plane that needs a 30K engine overhaul.

Peter

[wrenches and radios]

That cylendar sounds real good to me. The crack is no big deal I expect. Remember, If things are beyond limits they wont be in the log. Deffinently have a prepurchase inspection done for all the reasons mentioned. Get a cylendar pulled and have the cam looked at for corrosion especially if it sat for more the a couple of months since last overhaul.

I did one prepurchase inspection and walked away and called the agent to tell him the thing was not airworthy. Don't go on the fresh annual they are all advertised with. The engineer probably told the owner it was the last time he'd sign it off before something got fixed.

[Pat Richard]

my God,


It's spelled

CYLINDER

and

DEFINITELY

[eddyb123]

Thanks guys, this all good info. One clyinder was replaced already because of a crack. I would guess a good mechanic would look at the cam if he had a cylinder out already. The owner has given me copy of the logs from 06, and things were done at the owners discretion until he knew he was going to sell. He has now bought a twin engine, so to sell the first A/C he did all recommended work. The only issue is a crack in the tail cone. I'm waiting for him to let me know about that. Any opinions about the tail cone crack, and low comp. on one cylinder? Thanks for the help.

[iflyforpie]

If the crack is just in a fairing it might be alright since it is not structural-provided that the fairing isn't in danger of falling off or breaking.

I've never seen a cyllindar compression over 70 before, but if it is 60/80 it is still legal (just) and if it is a Continental they can go down to 45 or so if you use the calibrated orifice. A low comp on one sscilindre will definatley mean a rougher running engine and possible problems further on.

The best I can advise is to get an AME (one who hasn't seen the plane before) do a pre-purchase inspection.

[c170b53]

Your information is vague "crack in the tail cone" could mean anything and it means this is your first airplane and you need a mechanic.

[cgzro]

I would guess a good mechanic would look at the cam if he had a cylinder out already. The owner has given me copy of the logs from 06,

Ok listen up. Planes don't fly on paperwork. They fly because all the parts are working. First of all you need all the logs, especially the recent ones but defininitely not just '06, thats crazy. Not every annual is equivalent, some owners are ultra fussy and their mechanics respond to that with top of the line maintenance, others want cheap and their mechanics try very hard to keep the costs down but safe. Others are down right scary and sometimes find mechanics willing to live with that.

The plane and its logs should be delivered to a hard nosed mechanic of your choosing who will work for you and tell you all the things you need to know. Don't assume that when the cylinder was pulled the cam was checked.

You are not qualified to decide if the plane is airworthy or what it will cost to keep it airworthy. Hire a professional who knows what they are doing and listen to them. If there are things wrong, get estimates on the cost to repair and haggle with the current owner.

its a buyers market right now .. you can afford to be very fussy to get a good airplane.

I don't know where in the country you are but you should ask here for suggestions on a shop to take the plane too.

Oh, a crack in the tail cone can be unimportant, or can be very expensive depending on the type of plane, location and severity of the crack. If its just a screw on fairing then don't worry about it too much because its likely non structural and easy to repair. If its part of the monocoque structure of the tail .. well thats much more serious and expensive and you will need a proper airframe repair/patch which won't come cheap.

Another thing, don't let the compression of one cylinder keep you from buying a plane, or from doing much more checking everywhere else. A cylinder by itself is cheap/easy to replace, a camshaft or structural damage, rust is not. On many aircraft these days the camshaft is the most expensive single part of the plane!

Peter

[cold_start]

From my own experience.. I bought an aircraft that had a weak cylinder... 58/80 at pre-purchase on a Lycoming. The previous owner told me he though it was the piston rings which had all alligned. My mechanic warned the the cylinder may be bad, but since the plane hadn't flown recently, he suggested I get another compression check after flying it a bit (assuming I would buy, which I did)

The cylinder had a history of always being weak. Though usually around the fifties. After about 25 hours I got the test done and the cylinder had dropped to 48/80. All other cylinders were in the 70s.

The aircraft has had two annuals since and the compressions on that cylinder have been in the 70s.

On the last compression, two of my cylinders recorded 79/80 though. A number I though was pretty impossible.

After every flight - even after just running the engine - I'll run it at 1200rpm leanned to clean the plugs. Maybe that has something to do with it, maybe not.

Just my story.