Arrow gear won't retract

[ArrowFlyer86]

After takeoff when I pull the gear up normally I can feel the retract/extend in the pedals as soon as I pull the lever, and it's usually got a characteristic sound I can hear in the headset, too. Today after takeoff there was nothing. No gear-in-transit light, no pedal feeling, no sound, nothing. Gear stayed extended, so I confirmed with tower my gear was actually down and then landed.

Checked all the breakers, visually inspected around the gear to see if anything appeared out of place but came up empty. Everything looks normal. The fact that it didn't even try to retract the gear and just stayed 3 in the green makes me think there must be an obvious culprit that prevents it from even attempting to retract. Squat switch stuck on? Hydraulic system component not working?

Any thoughts on likely causes? Or any add'l information I can provide to help diagnose? Never had this before.

Wondering what kind of AMU this'll be, as I'm guessing xmas came early for my A&P.

 

[steingar]

Beats the alternative. The guys I was talking to today (to whom I think I might have sol the aircraft) one of them had a Mooney that was nicely painted in his care. Four days after it got out of the paint shop he took it flying and couldn't extend the gear, broke the emergency release bar trying. Belleyed the thing is with a prop strike. Right after a nice paint job. The pain guys bolluxed the reassembly of the nose gear.

 

[Dan Thomas]

After takeoff when I pull the gear up normally I can feel the retract/extend in the pedals as soon as I pull the lever, and it's usually got a characteristic sound I can hear in the headset, too. Today after takeoff there was nothing. No gear-in-transit light, no pedal feeling, no sound, nothing. Gear stayed extended, so I confirmed with tower my gear was actually down and then landed.

Checked all the breakers, visually inspected around the gear to see if anything appeared out of place but came up empty. Everything looks normal. The fact that it didn't even try to retract the gear and just stayed 3 in the green makes me think there must be an obvious culprit that prevents it from even attempting to retract. Squat switch stuck on? Hydraulic system component not working?

Any thoughts on likely causes? Or any add'l information I can provide to help diagnose? Never had this before.

Wondering what kind of AMU this'll be, as I'm guessing xmas came early for my A&P.

Most likely squat switch not closing as the weight comes off the gear, or the wiring to the switch has broken or a connector has failed. With the weight on the gear, the switch is open so that the pump can't run. Dirt and crud and grease and oil get into the switch and foul its contacts. The mounting might have shifted, too, so that the switch isn't being actuated. Wiring gets bent every time the gear retracts, and it can break inside the insulation. Connectors get old and crack and can come apart, or get corroded. It might even be an oxidized breaker. Lots of possibilities.

Some troubleshooting by someone who knows what they're doing is the way to get it fixed most economically. Don't let them just start replacing stuff until it works.

 

[Jim Carpenter]

Maybe a problem with the automatic gear extension system? (If your Arrow is equipped that way).

 

[Rgbeard]

It's either:

a simple electrical connection that's not connected properly. Squat switch, etc.
the gear-up solenoid ($100)
The hydraulic power pack (but the red light comes on, generally, so I'm discounting this)

or something else

 

[Dan Thomas]

Maybe a problem with the automatic gear extension system? (If your Arrow is equipped that way).

IIRAC, the auto extension was a hydraulic bypass valve that was kept closed by pitot pressure. It wasn't electrical, and the OP says the pump won't run. Many were disabled, as the pitot could ice up and drop the gear, adding more drag in icing conditions. Caused some accidents.

 

[Rgbeard]

Maybe a problem with the automatic gear extension system? (If your Arrow is equipped that way).

Not to be a nay-sayer, but I can't see this system malfunctioning in a way to cause the symptoms as described.

 

[ArrowFlyer86]

Maybe a problem with the automatic gear extension system? (If your Arrow is equipped that way).

So a little additional detail on that.

The first flight I did yesterday the gear didn't fully retract, the 'gear in transit' light remained on even though no gear showed that they were extended and locked (no green lights on). I couldn't get the gear to go back down with the gear lever. Moving it between up and down position made no impact. So instead I used the auto-extender to do it for me (pulled power, pitched up, and then it activates), and the auto-extender dropped the gear for me with no problem. I immediately landed just to visually inspect it. Then I reasoned with myself that it might have just been an anomaly so I decided to give it another go.

When I took back off is when I encountered the behavior in my original post - trying to retract that gear and nothing happens.

Sorry, perhaps I should have included that bit of detail originally in case it helps point to a particular culprit...

 

[hindsight2020]

Hesitation to retract with the pump running is a dying pump. No pump action in the up cycle (what I'm currently dealing with on my arrow) is an open or faulty connection, either the squat switch, the electrical switch at the autoextender system, or the up solenoid itself (more rare).

Yes, there is a second electrical switch in line with the squat switch, and it's located in the same lever that keeps the mechanical hydro valve closed on the autoextender. Normally held up by pitot pressure, or mechanically help up in place via override latch. But it functions the same way as the squat switch, and fails in the same modalities as the squat switch on the left gear does.

 

[Dan Thomas]

When I took back off is when I encountered the behavior in my original post - trying to retract that gear and nothing happens.

Sorry, perhaps I should have included that bit of detail originally in case it helps point to a particular culprit...

Electrical problem.

Shouldn't have flown it again. What if it had been a mechanical problem that made the gear impossible to extend again?

 

[ArrowFlyer86]

Electrical problem.
Shouldn't have flown it again. What if it had been a mechanical problem that made the gear impossible to extend again?

You got me there and I recognize it now. I figured I could count on doing the emergency gear procedure if that became the case where the gear wouldn't drop with the gear lever, because I didn't think it was a mechanical problem that would block the gear from lowering. Looking back I should have seen that.

I do appreciate the input on the root cause.

 

[ArrowFlyer86]

Just called a local shop to get on their schedule.
obviously not going to fly it again until that's fixed . I'll share the diagnosis once I bring it in.

 

[Rgbeard]

Get it up on jacks - do you have access to some along with the tailstand prior to the A&P arriving?

 

[mandm]

I think a lot of people misunderstand how the Arrow gear works, not saying that I know better either.

The Arrow has the auto-extension, pull the power back and the gear in transition light comes in after an extended period of time and the gear free falls and locks into place, you’ll have 3 green.

-> you should still put the landing gear in the down position
-> if one of the green is not working, pull the bulbs out and swap to another to check for a dead bulb, check panel lights are off (they dim the landing gear lights substantially)
-> some Arrows had the auto extension landing gear option disabled, know your Arrow, there is a second heated pitot tube on the pilot side fuselage above the wing that is used to detect prop wash and to activate the auto extension if no prop wash was detected
-> if you are practicing slow maneuvers or doing a gear up landing, there is a red lever on the left side of the manual trim wheel, pull the red lever up, and push a pin to the right to slide under the red lever, this will hold the spring loaded lever up and illuminate a flashing yellow light by the landing gear lights to indicate you have manually forced gear up

However it is not good practice to rely on the auto-extension landing gear.

If your landing gear does not operate, you can push the red lever down (on the left side of the manual trim wheel), same lever that you pull up to force a gear up. When you push the red lever down, it drops the gear and it free falls. The red lever is spring loaded and should return to the middle position when released. When the gear drops, the green landing gear lights will illuminate when locked in the down position.

-> You can activate the emergency gear drop as practice and immediately raise the gear after, and drop gear as you wish. There is no CO2 blow-out or one time use or manual turn handle to deal with like other airplanes may have. A lot of pilots refer to airplanes they have flown and think it’s a one off blow the gear down and done.

-> my mechanic mentioned something about hydraulic fluid and checking the levels (in the back behind the baggage compartment by the battery), but this is something that I haven’t fully grasped the idea yet.

Now if your gear is not doing anything, and no noise, your pump is not activating. I am not a mechanic but I would check your emergency gear lever to make sure it’s in the neutral position and check your fuses again. In my experience a bad fuel pump would trip a fuse when activated, so having no response is raising up some interesting flags. Maybe a wire came loose somewhere?

Some things to note with the gear. Depending upon your airspeed or AOA, I think the air hits the landing gear and/or doors at a certain way to cause incorrect gear light display. I experience this in some take offs and high speed descents. When operating your landing gear, do so at slower speeds to put less wear on your components (my personal opinion), same with your flaps. I try to be <110-120mph to drop the gear and <100mph to use first notch of flaps.

 

[hindsight2020]

Electrical problem.

Shouldn't have flown it again. What if it had been a mechanical problem that made the gear impossible to extend again?

I know what you mean from a risk aversion pov, but in fairness thats a risk every time one retracts a gear system. Mechanical jams are seldom telegraphed by electrical malfunctions, matter of fact they have nothing to do with them in hydro electric powered retract systems like light piston pipers of the vero beach variety. We re not talking mechanically linked assemblies like mooneys and bonanzas.

Failure to retract is the failure mode du jour for these pipers, as opposed to the cessna high wings. Not a distinction without difference in the least. Spesking of pearl clutching, I get a chuckle out of the autoextender adjustment procedure listed in the service manual lol. And they think experimental ops are reckless? Lol. /TC

--brk brk

OP, ill post my details once i get mine working again.

 

[ArrowFlyer86]

Get it up on jacks - do you have access to some along with the tailstand prior to the A&P arriving?

Sadly I don't have jacks. My current plan is to bring it into a shop on my field Monday morning who fit me into their schedule.

Now if your gear is not doing anything, and no noise, your pump is not activating. I am not a mechanic but I would check your emergency gear lever to make sure it’s in the neutral position and check your fuses again. In my experience a bad fuel pump would trip a fuse when activated, so having no response is raising up some interesting flags. Maybe a wire came loose somewhere?

Yessir, when the fuel pump went bust I had that behavior, a blown breaker. I've quadruple checked to make sure the all the breakers are OK.
Also it sounds like we have the same mentality for reducing wear&tear. I usually get down to about 110mph to drop gear, often times even lower.
(and yeah, I have the gear auto-extend feature... I never rely on it, but admit it was helpful because it dropped the gear for me when the normal gear lever wouldn't during that first flight... but by no means would I normally count on it to be my method of gear extension!)

 

[Dan Thomas]

You got me there and I recognize it now. I figured I could count on doing the emergency gear procedure if that became the case where the gear wouldn't drop with the gear lever, because I didn't think it was a mechanical problem that would block the gear from lowering. Looking back I should have seen that.

I do appreciate the input on the root cause.

I had the hydraulics fail on a 182RG on the jacks in the shop. Inside the control valve are several small plastic sealing devices that are in bores in the valve body, sealed by O-rings on their OD, and have a precisely flat fit against the rotor that the lever turns. One of those O-rings failed and bled off all the pressure, and no amount of dorking with the control lever or hand pump would get the gear down and locked. In that airplane, gravity won't get the gear down and locked; the mains have to be pushed forward and up against the slipstream. So in that airplane, and in 172RGs and 177RGs and 210s, getting the gear down relies entirely on the fidelity of the hydraulic system. One tiny failed 50-cent O-ring, in flight, results in a gear-up landing. I was just glad that it happened in the shop. Finding the blown seal was fun. I used a stethoscope, and probed all the cylinders and the control valve and hand pump while the electric pump ran, to find the leak, which makes a hissing sound easily heard in the stethoscope.

I did a prebuy and a whole lot of repairs on a Lake amphib. In those airplanes, the gear is actuated by cylinders, and the downlocks (and uplocks) are clever little things that rely on the last bit of cylinder extension. There's a hand pump for emergency extension. But the seller said that sometimes the gear wouldn't come all the way down; it would drop most of the way and then just sit there, at an angle and unlocked, while the pump ran. He had to work the lever and get the gear going up and down several times before it would finally lock into place. And he still flew it that way. I knew what was wrong: a bypassing O-ring in one of the actuators, and I found it inside the left main cylinder. Someone had used the wrong series of O-ring, a 100 series instead of the 200, so that its smaller cross-section was not compressed between the bottom of the piston's O-ring groove and the cylinder wall. It just kinda flopped around in there, and the oil just sneaked under it, bypassing and dropping the pressure to the whole system, until the lever-fiddling thing finally caught it up against one of the lands in the piston and it trapped the oil and brought the pressure up so the gear would work. Took all the actuators out and disassembled them and replaced all the O-rings. And the O-rings in the flap and trim actuators, too, since a leak in any of them could bleed off the pressure in the whole system.

See, in that system, too, the hand pump would not have gotten the gear down safely. You need the hydraulic pressure to lock it down.

 

[hindsight2020]

OP, for your reference (not my personal arrow, this is representative of the autoextender assembly in question however).

Note microswitch in red. It is in-line with the squat switch in the UP-cycle. Both the squat switch in the left gear, and the above switch highlighted must be operative and properly pressed in order to allow electrical power to the up solenoid. Normally air pressure (see picture for rod coming out of the diaphragm attached to the lever, but on the opposite side of the fulcrum) sufficient to overcome those springs, will swing that lever enough to close both the hydro dump valve (located under the metal casing, in the lower-most blue arrow), and make and keep that switch (in red) depressed.

Otherwise, the same effective action (in case of insufficient pitot air px, due to lack of speed for set spring tension, debris on the line, leak on the line, or diaphragm failure) can be accomplished by moving that lever manually from the front seat (override lever action). Oleo strut extension as weight comes off the left gear strut will press the squat switch. Then and only then will the electrical power will be fed to the up solenoid. That's why you're gonna have to check the electrical condition and actuation travel adjustment of both switches, if your symptoms include no green lights going out. Which intimates the pump never turned and put any pressure in the system to move any legs out of contact of their green light down microswitches.

Cheaper than assuming the powerpack failed and needs overhauling, though that could be it as well. I've had to replace a worn powerpack before, the symptoms were different, most notably some loss of gear lights as one of the legs gets moved before the pump trips out by breaker or high pressure switch (counterintuitive, but as the leg hangs mid throw because the pump is anemic, it trips the line px switch and turns off the pump before all legs can be tucked fully). If the pump is straight up burnt out dead or the solenoid went kaput, then yeah, it's gonna mask as a microswitch electric problem, since the gear lights will never show loss of contact in the down microswitches. That's why up on jacks it goes, and checking electrical continuity on those switches or wiring will be necessary to troubleshoot, before y'all go ripping out an otherwise working powerpack. Not cheap to overhaul these days with stupid inflation and the new hobby paradigm of everything taking 6-9 months, but I digress on that.

This is all for entertainment use only, and not meant as fAcToRy-cErTfid mechanical advice of course. I plea the fifth as to the absence or existence of hangar fairies in or around my domicile of record. In the words of the greatest deposition ever:

 

[ArrowFlyer86]

View attachment 112783

OP, for your reference (not my personal arrow, this is representative of the autoextender assembly in question however).

Note microswitch in red. It is in-line with the squat switch in the UP-cycle. Both the squat switch in the left gear, and the above switch highlighted must be operative and properly pressed in order to allow electrical power to the up solenoid. Normally air pressure (see picture for rod coming out of the diaphragm attached to the lever, but on the opposite side of the fulcrum) sufficient to overcome those springs, will swing that lever enough to close both the hydro dump valve (located under the metal casing, in the lower-most blue arrow), and make and keep that switch (in red) depressed.

Otherwise, the same effective action (in case of insufficient pitot air px, due to lack of speed for set spring tension, debris on the line, leak on the line, or diaphragm failure) can be accomplished by moving that lever manually from the front seat (override lever action). Oleo strut extension as weight comes off the left gear strut will press the squat switch. Then and only then will the electrical power will be fed to the up solenoid. That's why you're gonna have to check the electrical condition and actuation travel adjustment of both switches, if your symptoms include no green lights going out. Which intimates the pump never turned and put any pressure in the system to move any legs out of contact of their green light down microswitches.

Cheaper than assuming the powerpack failed and needs overhauling, though that could be it as well. I've had to replace a worn powerpack before, the symptoms were different, most notably some loss of gear lights as one of the legs gets moved before the pump trips out by breaker or high pressure switch (counterintuitive, but as the leg hangs mid throw because the pump is anemic, it trips the line px switch and turns off the pump before all legs can be tucked fully). If the pump is straight up burnt out dead or the solenoid went kaput, then yeah, it's gonna mask as a microswitch electric problem, since the gear lights will never show loss of contact in the down microswitches. That's why up on jacks it goes, and checking electrical continuity on those switches or wiring will be necessary to troubleshoot, before y'all go ripping out an otherwise working powerpack. Not cheap to overhaul these days with stupid inflation and the new hobby paradigm of everything taking 6-9 months, but I digress on that.

This is all for entertainment use only, and not meant as fAcToRy-cErTfid mechanical advice of course. I plea the fifth as to the absence or existence of hangar fairies in or around my domicile of record. In the words of the greatest deposition ever:

Thank you very much for this detailed diagram and explanation!
It's funny, while I can fly the plane well, detailed write-ups like this are a good reminder of my woeful ignorance to the question of "how" these components operate!
The shop told me to bring the plane in Monday morning and I'm hoping to look over the A&P's shoulder for a bit as he works to diagnose it. I'll try to steer them towards the cheaper/easier fixes before accepting an INOP powerpack. It sounds like there are a couple other explanations that could be it.

Just to confirm the behavior of the lights...
Last time I took off and pulled the gear lever, no "gear in transit" light illuminated, and the 3 green lights stayed illuminated green. Usually also there is an audible sound I can hear as the gear system goes to work, plus the feeling in the pedals, but nada now. It's as if the gear-lever was hooked up to nothing.

But I'll relay the root cause here after they're able to take a look (and while we hopefully eliminate the potential causes... in ascending order of AMU repair cost )

 

[hindsight2020]

Just to confirm the behavior of the lights...
Last time I took off and pulled the gear lever, no "gear in transit" light illuminated, and the 3 green lights stayed illuminated green.

Correct, that's usually electric. No electrical power is being routed to the up cycle of the pump, so nothing is happening. Doing that with the override engaged troubleshoots whether the electrical fault has anything to do with the extender diaphram. In this case nothing changes, so it can be either of the electrical switches (squat, or backup extender microswitch). Yes, it can also be a bad up solenoid, or even a gear selector switch, but those really fall behind in the probabilities column, historically anyways.

But that's gonna have to be troubleshot on the ground with a multi-meter, before it can be discounted and one starts looking at the pump having completely given up the ghost, which unfortunately can also be the case. Good luck and keep us posted.

 

[Dan Thomas]

The pump motor can be verified as shot or not using a jumper wire from the bus (master on, on the jacks) to the pump motor's terminal. If that makes the pump run, put that wire on the motor solenoid's coil control terminal to see that it's working, too.

 

[ArrowFlyer86]

@Dan Thomas
The pump motor was just discovered as the culprit here. They essentially did the above, hardwiring power to the motor and it won't run. They think the brushes on the motor wore out.
They're going to attempt to repair and if not we'll replace.

They said it's not the whole hydraulic pump and stuff, just the motor itself.

 

[Dan Thomas]

The airplane's Service Manual contains a lot of good, often ignored advice. The section of the Arrow III inspection checklist that deals with the pump motor brushes:



See that Line 7?



Note 19 gives the specifics on inspection periods.

So many mechanics just follow FAR 43 Appendix D for guidance. It's totally inadequate for complex aircraft.

 

[ArrowFlyer86]

Just got my invoice for the work done.

Curious how many shop hours people (more experienced than me) think are reasonable to throw the plane up on jacks, debug this problem and isolate if to the pump motor? Then remove it, pack it up for shipping for external repair, reinstall it, and test...

 

[TCABM]

Depends if the shop bills for time spent thinking about doing something.

 

[Bell206]

Curious how many shop hours people (more experienced than me) think are reasonable to throw the plane up on jacks, debug this problem and isolate if to the pump motor

In my experience, too many variables to guess like how many people working on it, what troubleshooting was accomplished, what references were followed, experience of mechanics, etc. Even if the shop is a CRS can tweak the hours. So if you're looking for a comparison on a task like this from start to finish it will be difficult.

 

[Dan Thomas]

Airplanes aren't cheap. Never were. I'm not saying that there are those that pad their bills; there are, but even without that the costs are high.

If those brushes were checked at annual, or at least at the 500-hour mark as per those inspection sheets I posted, worn brushes could be caught at that time, before they quit. Get the brushes and replace them before it goes on the jacks for the gear swings and it's done once.

 

[mandm]

I’m guessing most parts can be removed & reinstalled in an hour. I have no idea where the pump motor is, is it accessible or does it require some dismantling to get access to it?

Given an hour and minimum service fee, I would say $400-500. Add another hour for the jacks. $500-600 sounds reasonable for labor plus the part. I usually pay $100 to handle shipping and receiving the part and sending back the core. Given you haven’t shared the price I’m guessing $1500-2000 plus the part.

 

[ArrowFlyer86]

Thanks all. Yep I was just looking to see if experienced folks have a sort of benchmark for this. Sounds like there can be some variation.

This was 17hrs, 2050$ total.
The motor repair itself which was done by an external shop was about $275.

No question that owning a plane is expensive and this repair sure beats buying a new motor.

 

[mandm]

Thanks all. Yep I was just looking to see if experienced folks have a sort of benchmark for this. Sounds like there can be some variation.

This was 17hrs, 2050$ total.
The motor repair itself which was done by an external shop was about $275.

No question that owning a plane is expensive and this repair sure beats buying a new motor.

Hmm how much is the motor? Do you know where it is located or have any photos? $2050 is a bit much in my opinion.

 

[ArrowFlyer86]

I will say a big bonus is that I was able to get the fix done right away... Both the shops I called actually were able to look at it immediately, which was unexpected.

 

[ArrowFlyer86]

Hmm how much is the motor? Do you know where it is located or have any photos? $2050 is a bit much in my opinion.

From what the shop told me the motors are scarce these days and cost a few thousand dollars and might take a while to find. I don't know where one goes about finding those - so I'll have to take their word for it! Not sure what the availability is for an overhauled unit.

I'm glad to have the plane back even if I have to separate from a couple AMU for it. Just flight tested it tonight during IFR training and the gear worked great .

 

[mandm]

From what the shop told me the motors are scarce these days and cost a few thousand dollars and might take a while to find. I don't know where one goes about finding those - so I'll have to take their word for it! Not sure what the availability is for an overhauled unit.

I'm glad to have the plane back even if I have to separate from a couple AMU for it. Just flight tested it tonight during IFR training and the gear worked great .

Glad to hear you got it back already and are happy, that’s what counts! Didn’t realize the costs of the motor, ouch.

 

[Dan Thomas]

Some powerpacks are in difficult places. In the Arrow it's behind the baggage compartment, in the tailcone. Some interior paneling would need to come out to get at it, and that costs time and therefore money, so such places are routinely ignored even though the minimum inspection requirements in FAR43 Appendix D demand an inspection of "all systems" in places like that. It would also be uncomfortable inspecting stuff in there.

 

[hindsight2020]

The plastic access door to the tailcone is by definition modular. There's no need to remove paneling of consequence to R/R the Arrow powerpack. I suppose it would make it easier to work on if one did remove that entire plastic hatshelf, but it's certainly not necessary. I certainly expect an IA to suck it up and inspect the powerpack as part of an annual I'm paying over 20 hours for. In fairness, in 10 years I haven't had an issue with straight up malfeasance, but I have been victim of overbilling due to captive audience.

--break break--

OP,

Here's my last interaction with this line item, these are the good old days of 2017 (it's depressing how quickly inflation ran away in a mere 24 months {'20-'22}). Remote location, overhaul exchange to a shop in NV (airplane in TX) if I recall correctly. That overhaul price is probably closer to 3K on the part alone in 2023, though I haven't checked prices this year. So on an inflation adjusted basis, it's maybe a wash, as you didn't get an overhaul powerpack for your money.



I might get mine on jacks this week, hope the powerpack is not the culprit, as that's the spendy part.

 

[ArrowFlyer86]

The plastic access door to the tailcone is by definition modular. There's no need to remove paneling of consequence to R/R the Arrow powerpack. I suppose it would make it easier to work on if one did remove that entire plastic hatshelf, but it's certainly not necessary. I certainly expect an IA to suck it up and inspect the powerpack as part of an annual I'm paying over 20 hours for. In fairness, in 10 years I haven't had an issue with straight up malfeasance, but I have been victim of overbilling due to captive audience.

--break break--

OP,

Here's my last interaction with this line item, these are the good old days of 2017 (it's depressing how quickly inflation ran away in a mere 24 months {'20-'22}). Remote location, overhaul exchange to a shop in NV (airplane in TX) if I recall correctly. That overhaul price is probably closer to 3K on the part alone in 2023, though I haven't checked prices this year. So on an inflation adjusted basis, it's maybe a wash, as you didn't get an overhaul powerpack for your money.
View attachment 113021


I might get mine on jacks this week, hope the powerpack is not the culprit, as that's the spendy part.

I should know this, but is "power pack" synonymous with the motor that drives the pump?

Separately, if you got a new or overhauled unit plus labor for that price... I'd say you did notably better than me.

Is your gear giving you trouble again? Is that why it's going up on jacks?

 

[Dan Thomas]

I should know this, but is "power pack" synonymous with the motor that drives the pump?

A powerpack is a unified thing that has a motor, a pump, filters, a reservoir, pressure control switches and relief valving.

Here's an exploded view of one of the types of powerpack found in an Arrow, the Prestolite:



One of the two brushes is shown, #3.

 

[hindsight2020]

very simple contraptions indeed, for what they cost to overhaul (retail). Marine trim motors. ETA: @Dan Thomas beat me to it, see his post above.

Separately, if you got a new or overhauled unit plus labor for that price... I'd say you did notably better than me.

Is your gear giving you trouble again? Is that why it's going up on jacks?

On the first note, it's 2017 dollars. Today that job, provided no additional profit markup on the powerpack overhaul present, would be $2,751.62 according to the google-fu, and I think that amortization is low, vis real world. That was also in the epoch of normal supply chains, before everybody started using the "slow boat from China" excuse. So likely much closer to the 3K job I suggested before. Good deal? Meh, it's about par for the course. Certainly not on the parts front. Labor I don't begrudge.

On the second note, no not "again", rather "still waiting". Airplane went into annual able to retract gear. Came out of annual not being able to. Not an EAB so not in a position to start tinkering with hangar doors open, so I'm just playing it cool, captive audience thing. Plus legitimately not going anywhere for a while, so there's no rush. Sucks for the poor airplane, hasn't flown worth a damn in the past few years other than the great crossing of 2021, which was absolutely awesome. I'll update with the verdict. Cheers!

 

[Dan Thomas]

The powerpack in the school's R182 was showing the brushes getting a bit short. I went looking for the brushes, but nobody had any. They wanted to sell me a rebuilt motor. I made a bunch of noise toward a friendly Cessna dealer, who relayed it to Cessna, and they came up with brushes.

But that was in about 2009. It's a different world now. Even the motors might be scarce. That R182 was a 1978 model, and it's now 44 years old. How long should we reasonably expect to be able to readily source this stuff?

Maybe there's some outfit that has a huge array of brushes available, to fit motors in nearly every conceivable application. If they had some that were almost identical to the ones needed, maybe a bit longer or fatter, they could be ground down to fit. Would that qualify as an owner-produced part?

 

[ArrowFlyer86]

For reference this was my bill:


The 17.42 is the shop hours.

How long should we reasonably expect to be able to readily source this stuff?

That is a question I never asked myself when I was renter, but which I ask myself all the time as an owner.
I'm not familiar with what the rules are regarding what you're allowed to do if a part needed for your airplane is simply no longer available. If there are no more spare parts around - are you allowed to use a substitute of some kind? Do you need to get one custom manufactured?

And it's questions like these that help push me towards experimental for my next buy