Buying an older 172E - Items to Upgrade?

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AeroAl

Filing Flight Plan
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AeroAl
Good Morning folks,

Buying my first airplane (C172E) and have a few questions regarding some older style items that seem to work fine, but just wondering when/if you'd suggest I spend the time and money on upgrading. The list and my plans (sort of) are below:

1) Old Style pitot tube - Looks like a drain vent, and has the metal cover that flies open in the wind. - Seems to work fine and not expecting any icing, but if there's another reason you would suggest, please elaborate.

2) Generator System - Still running on a generator system that was overhauled recently. Not going to put any crazy electronics in there, because of the power draw, but it seems to work fine. In theory, I hear it's more reliable than an alternator, just allows for less power draw. Thoughts here?

3) Lights - Currently using incandescent lights, but plan on eventually replacing with LEDs. Especially with having a generator instead of an alternator. Any suggestions on lights?

4) ADS-B -Plan on using the UAvionix Tail Beacon in conjunction with the installed Mode C transponder (which was just re-certified) once the STC is approved next month.

5) Wet Vacuum Pump - A little heavier but more reliable apparently than a dry vacuum pump from what I've heard. Also overhauled relatively recently. I've heard from various people that wet systems rarely fail, and there's not really a reason to replace, just looking for consensus here.

6) Has the MOGAS STC - Plan on using MOGAS when available and AVGAS otherwise.

Anything else an E model might have that you'd consider looking at or getting replaced? It's currently in annual, so I expect everything will be airworthy when I pick it up. My plans for this aircraft are essentially to fly like crazy for the next 6 months and build 400-500 hours, so I'm sure stuff will pop-up along the way.

P.S. I didn't know if I'd like the manual flaps before I flew it, but after doing so, actually kind of prefer these to the electric flaps of the 172N models I have roughly 300 hours in.
 
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Recently sold a 172B that I loved. Used it for the first half of my IFR training. I had a newer pitot with heat, but would never go near icing with that plane, so an old style would probably be fine.

I had a generator and had to rebuild it once. Then another time my voltage regulator failed. I’ve got to learn the difference between that and an alternator. I only had radios and vors, so no massive avionics drains but it worked fine. I had an LED landing light I’d leave on mst of the time for visability. If I were to get adsb, I’d go for the tail beacon. The wing beacons seem to work well for people.

My wet vacuum pump was reliable, more than my AH.

So I don’t really have answers for you just wanted to say good luck and enjoy! We had a ton of fun in ours. I wish every plane had manual flaps.
 
Unless you’re planning on a lot of IFR I’d just upgrade the ADS-B and then upgrade the other stuff if/when it fails.
 
Generator doesn’t provide enough juice to keep the battery charged at taxi rpms. As long as you fly at cruise long enough to top off the battery every flight and don’t have to sit on taxiways for long periods, it doesn’t matter. A generator can provide as much juice as an alternator at cruise rpms.
 
The generator isn't more reliable than the alternator. It weighs way more, has far less capacity, and its brushes wear out like an alternator's but the generator brushes are far larger and more expensive than the alternator's. Generator regulators are more complex and are getting scarce. The generator won't even generate below about 1200 engine RPM, while the alternator will generate just fine at idle.

Automobiles started being built with alternators instead of generators around 1965. That says something.

LED landing lights consume about a fifth of the power of an incandescent, something to consider with a generator's limited capacity. Old avionics tend to use more power than new radios, too. A rotating beacon is a real drain. An LED beacon is the way to go now. There are LED wingtip nav light/beacon combos available. https://www.aircraftspruce.com/catalog/elpages/orion650eseries.php

During inspection, the mechanic needs to pay attention to the flap cables (wear and corrosion) and the bulkhead under the floor under the front of the rear seat. The cables run from the lever back and around four pulleys in that bulkhead, and the forces of extending the flaps pull forward hard on the bulkhead, sometimes breaking off the rivets that fasten vertical stiffeners to it.

The front spar in the horizontal stabilizer cracks around the hole in its center due to people pushing down on the stab to lift the nosewheel to turn the airplane on the ground. Don't do that. There's a service bulletin on it, SEB 94-8. The flap rollers and support arms bear watching, SEB 95-3.
 
Depends on how long you plan on keeping it,I would go with an alternator upgrade.
 
Salty said:
A generator can provide as much juice as an alternator at cruise rpms.
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Most generators have a capacity of 25, 30 or 35 amps. An alternator, as found in most light aircraft, produces at least 60 amps. It's one reason cars went to alternators when they became available.
 
Dan Thomas said:
The generator isn't more reliable than the alternator. It weighs way more, has far less capacity, and its brushes wear out like an alternator's but the generator brushes are far larger and more expensive than the alternator's. Generator regulators are more complex and are getting scarce. The generator won't even generate below about 1200 engine RPM, while the alternator will generate just fine at idle.
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Brushes and bearings are about $8.00 for the generator. electronic regulators are available at AS&S.
 
If it doesn't have shoulder harnesses, that should be first.

Shadden fuel flow meter is awesome and maybe a panel mounted USB charger too.
 
Tom-D said:
Most don't notice that the newer electronic draw a 10th the power than the old radios. The new type of permanent magnet alternators are much more reliable than the old type alternator and they weigh a lot less.

https://www.aircraftspruce.com/menus/el/alternators_0planepoweralternators.html

trash those old alternators as soon as you have reason.
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There are no permanent-magnet alternators in aviation. They all use an electromagnetic field; it's the way an alternator's output is controlled--by varying the field current. A PM alternator would need a variable resistance in the output, a massive thing requiring a huge heat sink and constantly draining horsepower from the engine.

The new starters, on the other hand, are permananet-magnet affairs. Powerful and compact.
 
Dan Thomas said:
There are no permanent-magnet alternators in aviation. They all use an electromagnetic field; it's the way an alternator's output is controlled--by varying the field current. A PM alternator would need a variable resistance in the output, a massive thing requiring a huge heat sink and constantly draining horsepower from the engine.

The new starters, on the other hand, are permananet-magnet affairs. Powerful and compact.
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https://www.aircraftspruce.com/catalog/eppages/sd20_alternator.php

sdaltreg.php
 
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Shoulder harnesses were already added to the front seats and there is a cigarette type power port added by the owner so those items are covered.

I’ll probably keep the generators at least until they need overhaul again, keep the wet vacuum, keep the current pitot configuration until it breaks, and I just preordered the tailbeacon for ADS-B Compliance.
 
1) Old Style pitot tube

Fine, leave it.

2) Generator System

Switch to an alternator when it dies.

3) Lights

Switch to LEDs ASAP. I like Whalen but pick your poison.

4) ADS-B

Tail beacon sounds fine for that airplane unless you want ADS-B IN someday.

5) Wet Vacuum Pump

Keep it.

6) Has the MOGAS STC

Nice to have. Carting around gas is a pain, though. Invest in some rubber mats to lay on the wings so you’re not trying to hold 5 gallon jugs up on a ladder. Or get a tank and pump and handle and watch how old the stuff gets if you’re going to burn lots of it. Airport might not like fuel storage or handling though. Depends on the airport.
 
Dan Thomas said:
It's still not a PM alternator. It uses a "field controller" (regulator).
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I think you are wrong, I've talked to their engineers on their tech. support line.
 
AeroAl said:
Shoulder harnesses were already added to the front seats and there is a cigarette type power port added by the owner so those items are covered.
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the 172, from day one had a cigarette plug provided as standard equipment.
 
Tom-D said:
the 172, from day one had a cigarette plug provided as standard equipment.
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Original was taken out for some reason or another, and a different one put in.
 
AeroAl said:
Original was taken out for some reason or another, and a different one put in.
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Wasn't there an AD put out years ago on the cigarette lighter in the 172? Sticks in my mind that the problem was there wasn't a fuse on some of them. So it was install a fuse or remove it. Hopefully someone with a better memory than mine will know.
 
Tom-D said:
This statement tells us that it is self exciting, It couldn't be unless it was a PM alternator.

the caution

Do not connect the BC410-H to an alternator controller/regulator that supplies 28 volts to the field — this may result in alternator damage, and will invalidate the limited warranty.

it is regulated, as all alternators are.
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Your reply seems self contradictory.
1) You say, based on the statement you quoted "it is regulated, as all alternators are."
2) But you also say that the caution statement ".... says it is self exciting, It couldn't be unless it was a PM alternator."

If statement #1 is true, then ALL alternators are permanent magnet type, but we know that's not true.
Statement #2 indicates the same caution statement says it has to be a permanent magnet alternator, but we know that can't be true from statement #1

This shows that "self-exciting" alternators use circuitry to indicate the alternator is running above a particular RPM and then generate voltage. They need not be permanent magnet.
https://www.powermastermotorsports.com/faq-alternators_a.html
 
Old Crow said:
Wasn't there an AD put out years ago on the cigarette lighter in the 172? Sticks in my mind that the problem was there wasn't a fuse on some of them. So it was install a fuse or remove it. Hopefully someone with a better memory than mine will know.
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I think you’re right. Seller mentioned something about an AD for the original lighter.
 
I owned a 172E ('64) for 22 years and made the following changes:

Cleveland brakes replaced the original Goodyear brakes
Heated pitot
"standard 6 pack" metal sub panel, plastic overlay panel and 3 inch gyros
60 amp alternator replaced generator
strobe anti-collision light vs motor drive unit
avionics "master" switch
replaced all ARC radios with more modern units over time

jrt
 
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