1974 Cessna 172M - Prebuy recommendations - Sioux City, SD

Reel Mountaineer

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Reel Mountaineer
I am looking at purchasing my my first airplane and unfortunately COVID is keeping me from traveling to look at it. The airframe has under 3000TT and it appears to have been well taken care of cosmetically. The engine has 900 SMOH. Does anyone have a recommendation what to look for and a good mechanic for a pre-buy? Thanks in advance, I appreciate any advice.
 
Did you get a good price? Can I have the sellers number so I can take a good look and steal the deal from under you? :p

All kidding aside, make sure the mechanic has never worked on the plane before. This helps to ensure the A&P/IA has no loyalties to the seller and can look at the plane with a fresh set of eyes. To illustrate the opposite side of the coin, if you hire the A&P/IA that's been annualling this baby for years, he/she is quite familiar with it and has made excuses for things that may/may not pass muster.

Before you plunk any money down for a pre-buy, enter into a contract with the seller. The seller will likely want a deposit, since you're tying up their plane and they want to make sure you have skin in the game. Make that deposit contingent on an airworthy aircraft and any airworthiness discrepancies will either be paid for by the seller or he will give you back your deposit and pay your mechanic for his/her time.

Watch Mike Busch on YouTube and he'll talk about the anatomy of a pre-buy.

I could go on, but that should get you started. I'm on my second Skyhawk. First was 2009. This past one I picked up in November. I bought sight-unseen (aside from pictures on Trade-A-Plane and from the IA that did my prebuy). It carried a LOT of risk, but the price was right and I got lucky. It could have gone the other way and I could have gotten burned.

Best of luck and KEEP US POSTED!

Stay safe and happy flying.
 
how do you know the klutz that is doing the inspection is any better than any other inspector?
 
Congratulations! You’ll love the 172. This purchase shouldn’t be that difficult but as far as recommending a pre buy the POA folks would need to know a location of the plane (South Dakota?). As for what to look for, I will keep it simple.

1). Does everything work on the plane? Cockpit lighting, landing lights, radios, guages etc

2). Corrosion? Has it been treated with Corrosion X? Many A and P’s will routinely treat planes every other year with Corrosion X especially if the plane has a coastal history. Bad corrosion will be a deal breaker.

3) Seats, especially pilot side seating. The 172 have a legacy and history with seats and seat rails. Fixing is pricey but the consequences of a seat stop failure on takeoff is probably fatal.

4). Engine? Check the obvious such as compression etc. but take a little look at the baffles and exhaust risers. We have had issues there.

5. Front strut. Has it been rebuilt? Much has been written about front strut shimmy usually on landing. Fix is a rebuild of the front strut.

Good luck going forward. I have a 172L model and love it.
 
Did you get a good price? Can I have the sellers number so I can take a good look and steal the deal from under you? :p

All kidding aside, make sure the mechanic has never worked on the plane before. This helps to ensure the A&P/IA has no loyalties to the seller and can look at the plane with a fresh set of eyes. To illustrate the opposite side of the coin, if you hire the A&P/IA that's been annualling this baby for years, he/she is quite familiar with it and has made excuses for things that may/may not pass muster.

Before you plunk any money down for a pre-buy, enter into a contract with the seller. The seller will likely want a deposit, since you're tying up their plane and they want to make sure you have skin in the game. Make that deposit contingent on an airworthy aircraft and any airworthiness discrepancies will either be paid for by the seller or he will give you back your deposit and pay your mechanic for his/her time.

Watch Mike Busch on YouTube and he'll talk about the anatomy of a pre-buy.

I could go on, but that should get you started. I'm on my second Skyhawk. First was 2009. This past one I picked up in November. I bought sight-unseen (aside from pictures on Trade-A-Plane and from the IA that did my prebuy). It carried a LOT of risk, but the price was right and I got lucky. It could have gone the other way and I could have gotten burned.

Best of luck and KEEP US POSTED!

Stay safe and happy flying.
Thanks Nathan, I was thinking exactly what you said...lots of things to go wrong and I’m carrying the risk. The price is a little high ($85k) it has a 530 and needs ADSB but is a cream puff. I think 172’s are high right now in general. I wonder if the prices are going to start coming down with all the parked airliners and how fast we can reopen the economy and it takes off again. I appreciate the video, I may look you up next time I’m in town I work in that funny shaped building for reserve duty. Thanks, - john
 
Congratulations! You’ll love the 172. This purchase shouldn’t be that difficult but as far as recommending a pre buy the POA folks would need to know a location of the plane (South Dakota?). As for what to look for, I will keep it simple.

1). Does everything work on the plane? Cockpit lighting, landing lights, radios, guages etc

2). Corrosion? Has it been treated with Corrosion X? Many A and P’s will routinely treat planes every other year with Corrosion X especially if the plane has a coastal history. Bad corrosion will be a deal breaker.

3) Seats, especially pilot side seating. The 172 have a legacy and history with seats and seat rails. Fixing is pricey but the consequences of a seat stop failure on takeoff is probably fatal.

4). Engine? Check the obvious such as compression etc. but take a little look at the baffles and exhaust risers. We have had issues there.

5. Front strut. Has it been rebuilt? Much has been written about front strut shimmy usually on landing. Fix is a rebuild of the front strut.

Good luck going forward. I have a 172L model and love it.
Possum,
thanks for the note...I will add these to my list. Seller disclosed some panel backlighting is out and other than not having ADSB said it was good to go. I appreciate the tip on corrosion, I’m in FL and will do it even though we are 80 miles from the coast. Compressions are all in mid 70’s within a couple pounds of each other. I will research the strut also. Thanks for your help! - John
 
Busch elicits strong emotions on both sides, but when I buy my airplane, it is my intention to engage his savvy prebuy service. For $750 they'll recommend a shop they trust, provide a list of problem areas to be checked, oversee the process, and help negotiate the purchase price if problems are found. Seems cheap to me.
 
I have a M model. I’ve owned it for 19 years. I’m also the A&P. I’m not an IA, just an A&P. I like using an IA for a second set of eyes. I’ve been through a lot with this airplane and feel that I know it pretty well. I’ve dealt with every issue that everyone has mentioned so far. Recently we updated the avionics with a 650xi, G5’s, and a GI275 MFD. The ”M” is possibly the best 172 every made. Maybe not for fitting avionics, the N is better for that:)
If it’s been in a hanger you could really have yourself a sweetheart there. Not a dealbreaker if it hasn’t, just more issues to workout.
Here’s a few questions for you, along with some items to consider.
-Damage history? Check the log books carefully.
-Hangered or not? Sun and corrosion does more damage than anything in my opinion. I’m in a hanger now but mine has been outside (covered) a lot over the years. I’ve worked my ass off staying on top of this and my plane is unbelievably clean because of this hard work. Someone mentioned that corrosion might be a dealbreaker. I wouldn’t go that far. It’s got corrosion. You can bet your ass is has some corrosion! Even if it has been treated with corrosion x or whatever. That stuff is great but it can’t get everywhere. We’ve treated inside the wings, tail, everything. I still find corrosion occasionally. I’ve always been able to take care of it and spot treat as needed. Recently found corrosion on the underneath side of the glareshield and under on the inside of the firewall. It all cleaned up and was painted during avionics installation.
What state you getting it from? Or where has it spent most of it’s life? Hopefully a dry climate.
Engine. Do you know which one. I’m guessing its an 0320-ETD. If so, it’s one of the best ever. The H model had some issues, not a big deal but it got a bad reputation which hurt it’s value. Someone mentioned exhaust/intake leaks. Of course this should be looked at but it’s generally not a big deal. I just put new intake gaskets and hoses on mine this week. Parts were only maybe $40 bucks. Obviously my labor was free but it only took an hour or two.
Engine hours: You said it has 900hrs. That’s doesn’t really matter much. Recommended TBO is 2000 but even that is not a requirement for most. A lot of people think that hours are the main concern. It’s not. Time (years SMOH) is probably the biggest deal in my opinion.
How many years has it been SMOH? The lycoming letter states 2000 hrs or 12 years I think. Most people never consider the second part. Neither is regulatory in most situations but it’s definitely something to consider. This Lycoming letter saved me a ton of money when I went through my divorce. The appraisal got slashed due to considerable years SMOH:) If it’s been 15-20 years SMOH I would be check next to see if a top overhaul has been completed. If so, did they go with new or serviceable cylinders? Big difference price, and quality based on my experience.
Mags are another expensive item. They have really gone up in price. I put a brand new set with harnesses on not long ago. Check to see when the magnetos were overhauled or replaced. This has gotten to be a big deal recently. There’s a new service bulletin that’s pretty important to comply with. Not required, but important.
Seat rails: Someone mentioned this. Yeah, it’s always been a problem but it’s really not that big of a problem for a private owner. I put a new set in but if yours pass inspection you’ll probably be good for a long time. Flight schools are always wearing them out because the seats get moved about a lot. Once it becomes your personal airplane you won’t be moving the seats around that much, and when you do you’ll be careful not to drag the pins, you’ll place them in the holes instead:)
Nose strut: Yes this is a bit issue in my opinion. It doesn’t matter if it has been rebuilt. It’s still a freaking issue. Actually, I would prefer it not to have been rebuilt. At least then I know it’s hasn’t been leaking down in the first place.
What is a strut rebuild anyway? Depends on who you ask. Most mechanics just put the majority of a seal kit in. Most pilots consider that a rebuild. I can assure you that most mechanics only replace the seals that they think are bad (the easy ones) and usually they are right. I’ve “rebuilt” mine this way 3 times over the years. It wasn’t until recently that I got determined and really took this thing down to the bone. Actually, I’m just finishing up a full rebuild on mine now. This includes the upper o’ring, and lower 2 o’rings, that nobody ever replaces. I asked a mechanic bud of mine if he’s ever replaced the lowes. He said absolutely not, because it’s a pain, and they hardly ever leak there anyway. Not only do I have a full rebuild now, I located some more corrosion that I would never have caught otherwise.
The one item that never gets looked at is the outer steering collar. I talked with an ex-engineer from Cessna last week. He said it’s probably the most overlooked item on the nose gear. I believe it! It’s a total PIA to get it apart because of the huge snap ring. Mine was full of rust. About a hundred needle bearing in there. It has a grease fitting, but Cessna didn’t put internal groves to carry the grease in a number of the 172s. Even if it has internal tracks, all it takes is for it to become clogged and the rust forms. Thankfully, I was able to clean them up ok with gas. Then I let them soak in oil. Finally got them repacked properly with grease. So nice now!
Have it check for shimmy or play in the nose gear. People say that Cessnas are supposed to shake. That’s a bunch of BS. Get it right up front. If it’s shaking, you have work to do or it will get worse. I’m kinda anal about the nose gear being right:)
 
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Do you have copies if the log books to review? If not, ask why not. So many of us digitize logbooks these days, that sending a cd of the books is trivial and good marketing. You can have your shop review them before continuing the deal.

Also, you can order the CD from the FAA for something like $5. The current owner doesn’t get to veto this info, it contains all the 337s and everything reported to the FAA. Another source of factual info
 
172s have their weaknesses. Cessna's service bulletin listing is here, but it takes a lot of clicking and reading to find the applicable documents:
https://www.startpage.com/do/dsearc...b&pl=ext-ff&language=english&extVersion=1.3.0

Stuff to look at real close:

The stabilizer front spar cracks when people push the stab down to turn the airplane on the ground. The stab nose ribs near the fuselage get crushed, too.

Rudder hinges--the ones on the rudder itself--crack when they get fatigued after too many tailstrikes. That big lead mass balance weight up top does it.

The rear doorposts crack right at the bottom when they flex as the airplane taxis over rough ground. Hard to see, but if the mechanic take a light and small brush and has a look at the tight little radius right where the doorpost meets the gear box aft bulkhead, he might see the edge of the crack. Otherwise the back seat comes out, carpet comes out, plastic doorpost cover comes out, and a good look forward from behind the doorpost, near the aileron cable pulley, will see it.

Some serial numbers had an issue with the forward doorpost cracking at the lower door hinge. Got to take the trim off and look through the hardware access hole to see it. I think the '74 model is outside the affected s/n range.

The fuselage bulkhead right next to the baggage door cracks down low, near the floor. Plastic trim has to come off to see it. When Cessna put the rear window in (1962?) they lost some fuselage rigidity, and it flexes in flight, distorting that bulkhead and fatiguing it.

Seat rails wear out. The roller housings on the seats can wear out. The locking pins very often don't go in far enough to satisfy the AD. The infinitely-adjustable seats have problems: the seat base (the frame that carries the bottom cushion) has four forks that hold it to the bellcranks, and those forks crack due to side-loading as people slide in and out. The seat backs on those seats use 3/16" clevis pins that ride on the adjusting cam, and I've often found them worn almost all the way through. A seat-back failure is as bad as a seat rail lock failure.

Control cables wear and fray at the cluster of small nylon pulleys in the cabin ceiling. There's an idler pulley in each wing that an aileron cable rides on, and they're often seized solid. That wears the cables. Same can apply to many other pulleys in the system. 1974 is a long time ago, and lubricants dry out
and bearings corrode.

The fuel tanks are riding on rubber bumper strips that harden and crack and fall off the structure and hold-down straps. Then the structure and straps start eating into the tank. Expensive.

The firewall cracks at the lower cowling shockmount brackets at the oil cooler level.

The engine mount cracks at the welds on the lower crosstube. Cessna added reinforcing finger-patches at some point, but I think it was after 1974.

And the usual old fuel and oil hoses, including the short hoses that connect the fuel vent crossover line in the cabin ceiling. Too many folks keep thinking airframe hours instead of years. Airplanes rot whether they're flown or not. Then there's old master and starter contactors and so on.

And no, rebuilding a nosewheel strut does not cure shimmy. It masks it, like painkillers given to a cancer patient. The cure is a different thing that I'm tired of promoting. I'm retired now and can't be bothered with the arguments anymore.
 
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What he said! Right on DT.
 
Busch elicits strong emotions on both sides, but when I buy my airplane, it is my intention to engage his savvy prebuy service. For $750 they'll recommend a shop they trust, provide a list of problem areas to be checked, oversee the process, and help negotiate the purchase price if problems are found. Seems cheap to me.

Their log review is actually free. Then you can avail the pre-buy service and you can convert that to their annual maintenance service and be covered for one year where they manage everything
 
I don't know any A&Ps in the area, but are you talking about Sioux CITY, which is in Iowa, or Sioux FALLS, which is in South Dakota? Granted, there is a North Sioux City in SD, which also has a small airport.
 
The fuel tanks are riding on rubber bumper strips that harden and crack and fall off the structure and hold-down straps. Then the structure and straps start eating into the tank. Expensive.

excellent point. I'm currently working on the annual of my C172M, taking advantage to being out of work due to the crisis. Every annual I do one or two extra items of PM on the plane. This year was the copilot side fuel tank, removed the tank cover probably for the first time since the plane was constructed. Did this to inspect the tank and to replace the rubber strips. This is what I found.
 

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And the usual old fuel and oil hoses, including the short hoses that connect the fuel vent crossover line in the cabin ceiling.

Another excellent item, all rubber materials have a certain lifetime, and need to be replace. These hoses on the crossover lines never get looked at because they are a PIA to work on. The older the hoses are the more difficult they are to remove. Most shops never do this unless you request replacement, the you pay for the labor. Another item I've done during annual time.
 

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The ”M” is possibly the best 172 every made. Maybe not for fitting avionics, the N is better for that

yes I love my M model! Curious about your comment regarding M Vs the N model for fitting avionics, I thought that the airframe for both models was the same? Why is the N better for fitting avionics?
 
@Dan Thomas, good post. Every Cessna owner should turn their front seats upside down and look at the rollers. You might be amazed at how worn they are. In my G model the rollers take about 3 minutes each x 4 rollers per seat. The kit is relatively expensive, but it's a simple fix and you might be amazed at their condition. https://www.aircraftspruce.com/catalog/appages/cessnaseatcomp.php?clickkey=20467
Old: IMG_2960.jpg I wish I'd taken a better picture to show how terrible the condition of the rollers were.

New: IMG_2961.jpg Much more betta!

I just replaced my seat rails and went with the screw kit instead of rivets. My A&P/IA let me do some of the labor like drilling rivets. The rails and necessary accessories came to about $1200. If I had dropped if off and had him do everything himself including corrosion repair, priming parts, spot-facing the rails, etc. I'm guessing it would have been another $2500. It's not difficult work, but it is labor intensive.

Old:IMG_2948.jpg
Transfer holes using template: 60470079571__0EAF3D0C-DAA3-4007-833A-3808DCD173C8.JPG. Despite the FAA instructions which are confusing, every hole must be spot-faced (McFarlane has the bit) regardless of the actual screw/nut combo used.
Test fit: IMG_2949.jpg Also, the Cessna seat rail stop bars do not fit out of the box, even if you buy new ones. Before you install the rails, be sure to file the proper locations in the rails to allow them to fit. I called McFarlane and talked to Support. I was told this is the correct method, do not attempt to grind the stop bars to fit, there's not enough material.
 
Another excellent item, all rubber materials have a certain lifetime, and need to be replace. These hoses on the crossover lines never get looked at because they are a PIA to work on. The older the hoses are the more difficult they are to remove. Most shops never do this unless you request replacement, the you pay for the labor. Another item I've done during annual time.
Those rubber hoses get HARD over time and are a PITA to remove. I found the right wing side was leaking after doing some spins. Stained my headliner! These posts remind me how much time and effort I've put into keeping her airworthy. The list of things to check is endless it seems, good luck with finding and getting a good prebuy @Reel Mountaineer.
 
excellent point. I'm currently working on the annual of my C172M, taking advantage to being out of work due to the crisis. Every annual I do one or two extra items of PM on the plane. This year was the copilot side fuel tank, removed the tank cover probably for the first time since the plane was constructed. Did this to inspect the tank and to replace the rubber strips. This is what I found.
Yup. You can see the metal strap in contact with the tank in that photo. Bumpers all shrunken and falling off. If it's left long enough the strap chafes through the tank. That's the expensive part: drain the fuel, take the tank out, steam-clean it, get it tig-welded, and reinstall everything with new rubber bumpers and vent line hoses. Cessna recommends that the tank covers come off every three years or 1000 hours to check this area, but of course I have found them never to have been removed. Sometimes the cover screws were rusted into the anchor nuts and have to be carefully cut out and the anchor nuts replaced. If the affected nuts are in the front spar, we are faced with a major headache. The anchor nut rivets are underneath the leading edge skin. On a prebuy the mechanic should try loosening a few of those screws.
 
@Dan Thomas, good post. Every Cessna owner should turn their front seats upside down and look at the rollers. You might be amazed at how worn they are. In my G model the rollers take about 3 minutes each x 4 rollers per seat. The kit is relatively expensive, but it's a simple fix and you might be amazed at their condition.
The AD damands that the seats come out during the inspection. I have often wondered how some of the stuff I've found went undetected if the seats had actually been taken out; I suspect (no, I'm certain) that previous inspections were just quick glances at the seat without taking it out, based on the scary stuff I found. The AD also specifies that worn roller washers be replaced, but I've found those long-ago shot. The Cessna washers are just punched-out bits of the ABS plastic interior sheeting and wear out in no time. McFarlane sells a washer that's cheaper and about a hundred times better, being made of Delrin, a material designed for abrasion resistance. Missing washers means that the roller housing chomps at the seat rail. I think Aircraft Spruce's kits are McFarlane kits.

Never oil or grease the rollers. The AD prohibits that. Lubricants attract dust which causes roller seizure. Cessna does recommend rubbing a bit of paraffin on the underside of the seat rail's top flange; that helps prevent sticking and galling of the aluminum rail and aluminum roller housing tangs.
 
Those rubber hoses get HARD over time and are a PITA to remove. I found the right wing side was leaking after doing some spins. Stained my headliner! These posts remind me how much time and effort I've put into keeping her airworthy. The list of things to check is endless it seems, good luck with finding and getting a good prebuy @Reel Mountaineer.
Slit the rubber hose with a utility knife, very carefully, and just a little depth at a time so that you avoid nicking the tube. Once the rubber is cut partway through you can rip it the rest of the way and peel it off. Pretty much hopeless trying to slide it off the tube.
 
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