« Posts tagged engine

Idle fixed.

5.5 hours.

 

I don’t have time for a lot of jibber-jabber, so I’ll make this short and sweet:

I installed the new idle linkage bearing and spent a bit of time dialing in the idle.   I got it to idle smoothly at 750 RPM with a solid transition to power on throttle advance.   CHT’s sitting there uncowled don’t get past 245, which is good.   We had a really strong wind today, so it was a good day for engine testing, but a crap day for flying.  Nobody was out there, so I was left to my own devices.  The idle fix took about two hours, so then I went for a drive.   I taxied down to the west end of the runway, then came back.   20+ knot winds variable from 070 to 085 make for some fast footwork on the pedals.

After that was done, I set about making the fire extinguisher mount.   I ended up putting it on the fuel pump cover, in easy reach of both pilot and copilot.  Of course, if the fuel pump’s on fire, getting the the extinguisher is going to be interesting.   I had to reinforce the fuel pump cover with some .032 so the bracket could be safely bolted on, but it seems to work.

 

Zero Sum

6 hours.

I spent a whole lot of yesterday doing various things, which is the surest way to feel like I got nothing done.   I had two goals: Fix the idle stumble and run down that AP engage joystick wire issue.

The first part was almost easy.   I set the mag timing to 25 degrees per the engine data plate.  I’m getting to be an old hand at setting mag timing.  I got them both firing in sync, then made the idle richer by a couple of flats of the adjustment linkage, per the AFP manual.  Sure enough, that cured the off-idle stumble and my CHT’s and EGTs dropped noticeably.  But there was still a rough idle, so more adjustment needed to happen.

The manual says that adjusting the idle is done with the engine running.  The problem with that is twofold: One, working near a spinning prop scares the crap out of me.  I haven’t had the training to do so safely.  Two, because of the orientation of the throttle body, the idle linkage is on top, between the throttle body and the engine case, and the only way to get at it is by reaching past hot exhaust pipes.  Even if I did have the stones to crawl under there with the prop spinning, I can just see burning my forearm on the #1 pipe and yanking it back into the arc of the prop.  No thanks.  I did my idle adjustments with the engine off.

With Mike as the casual observer, it appeared that my idle was too rich, because there was a bit of smoke coming from the pipes when I was idling and the idle was definitely a bit rough.   This is caused by multiple symptoms, but a too-rich mixture is the first and most obvious culprit.

The manual also says that the best way to adjust the idle is to leave one of the jam nuts “just snug” and turn the block one flat at a time.   Well, yours truly interpreted “just snug” as “don’t touch” and after a couple of turns of the block, the left-hand rod end bearing snapped off at the jam nut.

BrokenBearing

So now I have to find/buy a LH thread #3 rod end bearing and I can get back to business.

As for the other stuff, I did chase down the AP engage wire.   Turns out I have to figure out a way to do some kind of voltage differential and use the MGL script editor in order to remote-control the EFIS to engage the autopilot.   A simple “Hey, I’m Grounded” won’t work.   This will take a minute to work out the logic, but I’ll email Matt at MGL and see what he says.

Also, Owen and Ron got the racing scales, so I can do weight and balance.    This gets done first thing today, because I need to return the scales ASAP.   It’s   I’m just hoping the W/B comes in as expected.

I also fiddled about with the wheel pants, but that’s not high on the priority list right now.

“Twas the Weekend Before Christmas, and All Through the Hangar…”

4 hours.

“Not a creature was stirring, save this rivet banger…”

This encompasses Saturday through Monday.

With the holidays in full swing, the schedule gets a little weird, but better, because I have a few days off.   I’m keeping a decent balance between building, home obligations, holiday festivities, and the occasional video game.   I’m also coming to terms with the fact that the endgame for this project is approaching rapidly, or so it seems to me.   Last weekend, I’d started on the gear leg fairings.   This weekend, I pretty much got them done.

The most important thing with the gear leg fairings is to build them without any twist in them.   They come taped together from the factory, but Van’s fiberglass is usually so crappy for fit, I didn’t trust them.   The way you verify no twist is to put the leading edge on a flat surface and using a square, insure that both trailing edges line up.   Once that’s done, you can use the full-scale template cut from the plans to mark all the cut lines.   Easier said than done, though.  You really need two squares, one for each end, and another pair of hands, or at least a boatload of tape.   But I found a solution in our hangar that worked very nicely:

IMG_1710That brass thing is a piece of channel from one of those godawful floor-to-ceiling mirrored sliding doors, usually found in cheesy SoCal apartments that saw their last renovation some time before Saddam Hussein rolled his tanks into Kuwait City.   But it makes a very nice, very straight jig for lining up the trailing edges of the gear leg fairings.   Not only that, it provides an excellent platform for match-drilling the hinges.   Some of you are looking at this and saying “hey, those are the wrong size hinges!”  Yes they are.   But it’s what I had.   I used up all my 1/16″ piano hinge on various attempts at the cowl.   If it should come to pass that these hinges cost me knots and fuel, I’ll change them out, but at this point, I want to be done.

IMG_1711

A selfie, checking the alignment of the hinge.

With those done, I could check out the fit of my intersection fairings.

IMG_1712

Upper intersection fairing fits, sort of.   It needs some work.   It’ll also need to be taped into position to hug the contour of the fuse and cowl, and then a couple of layups on top of that.   After that, it gets trimmed back to where it’s supposed to be.   Van’s fiberglass may be crap, but it’s better than mine and it sure beats fiddling around with modeling clay.

Monday was all about tying up as many loose ends as I could before starting on the wheel pants.   This meant, among other things, getting as ready for the inspection as possible.   I attached the ‘EXPERIMENTAL’ sticker to the roll bar:

IMG_1707

This is a bit redundant because the baggage bulkhead cover that came with the interior has it embroidered into the leather, but that won’t be installed during the inspection.   The canopy frame covers this one up when the canopy is down, but I don’t think that matters.   If it does, those stickers are cheap.

IMG_1709

This is required by the Feds to be in the airplane in plain view of the occupants.  It’s like a magic amulet to ward off the unadventurous.

Left Gear Leg

Left Gear leg

Left Gear leg works much the same way.

After this, I spent some time doing odd jobs.   I safety-wired the tailwheel chain hardware, then moved to the cockpit, where I zip-tied the wires made loose by the magneto troubleshooting and the addition of the OAT probe.    I also attached bolts in the center section per Van’s SB 12-08-14.   Apparently enough people forget this step that Van’s thought it merited a Service Bulletin.   Guess what?  I forgot it too.   In addition to the close-tolerance bolts that hold the wing spars to the center section, there are two on each side that secure the center section to the vertical bar on the wing spar.  These need some AN4 bolts in there to lock things down.

Part of getting airworthy is checking all the relevant SB’s and AD’s to make sure you don’t have anything hanging in the breeze that might kill you.   The rules on experimental aircraft and AD’s are fuzzy, and are interpreted by various people in various ways, because different sections of the FAR’s appear to contradict each other.    But the safe thing to do is check for AD’s and SB’s that apply to your stuff and fix them if you find any.   If I hadn’t gone through this process, I wouldn’t have found those missing bolts and the inspector would have.

When I moved on to the engine, I discovered some oil running down from the spacer on the right mag and at the oil drain fitting of the #1 cylinder.   This was alarming enough to merit a quick engine test.   I cleaned off the oil and wheeled it out to start up, to verify that the oil was new and not left over from the last time I had to loosen them up to get to one thing or another.

I did a quick runup and brought the cht’s up to operating temperature, but even with good, timed mags, it still stumbled off idle.   Advancing the throttle slowly would bring the RPM up, but moving it smartly, like I would for takeoff, killed the engine.   After consulting VAF and then my AFP manual, it looks like my idle mixture is set too lean.   This will need to be corrected, and I can probably do this tomorrow.  The good news is that I didn’t see any new oil in the spots where I found the drips, so it looks like the oil around the mag spacer was from when I had the mags off, and the oil from the #1 drain line is from the time I had to undo the fitting at the cylinder head to get at either the bottom spark plug or the EGT probe.

 

 

[Untitled]

5 hours.

Today was about putting things back together and getting a handle on some of the chaos.   The first bit of good news is that the oil temperature probe works fine.  I pulled it out of the engine and hit it with a heat gun and sure enough, it gave me a reading.  So I’m not going to worry about that anymore.   I secured the wires back in their bundle and i’m calling that squawk done.

I also wasn’t real happy about the weird way I had the fuel pressure sensor set up.  The Adel clamp holding it was maybe a size bigger than it should have been, and this way seems more secure:

IMG_1572

As I mentioned last time, I flipped the governor arm over and it seems to work just fine:

IMG_1570

My biggest problem with doing it this way was where the injector line was going to go.   A piece of angle solved that.   Now it’s out of the way, and less likely to be heat-soaked down near the cylinder.  I still haven’t safety-wired the screws yet, or put the cotter pin in the cable attach nut, But I think this is how it’ll stay.

Last week, Owen recommended tightening up the tailwheel chains.   Van’s recommends a half an inch of slack, but if you ask ten different people how they like their tailwheel chains, and you’ll get at least five different answers. But my chains had an inch of slack, and if I took a link out, I’d have none.  But I did take a link out of each side, and while there isn’t really any dangling slack, I can move the chains up and down by about a half an inch, and I’ll tell you, based on today’s test, it taxis just fine:

IMG_1571

That little gap in the rudder fairing is kind of annoying.   Not exactly sure what to do there, except put nutplates in there and hope for the best.

Today’s test was all about seeing how things went with the cowl on.  First, I wanted to make sure I could actually get the cowl on with the flipped-over governor bracket making the cable rise a bit more than it did before.   Turns out, I’ve got about 1/8″ of clearance between the cable and the top cowl, which is good enough.   And from what I remember, the cowl inflates a little in flight, so that 1/8″ becomes a little more.   And that’s fine.   I just don’t want to have to put a clearance wart in the cowl to accommodate the cable.

IMG_1573

But before taking it out for another test, this adjustment had to be made to the baffle material on the lower cowl.  I had to cut it back a bit, because it was covering up about 6 square inches of air intake.   Bad.   So with this mod in place, I put the top cowl on, and pinned it down.   Then I put a few of the floor panels in, and you’d be surprised how much the plane stiffens up with the reinforcing action of the panels.   I ran it up, then shut down the left mag.  Engine died.   Started it again, repeated.   OK, right mag dead.   Grr.   Still runs fine on one though.

So I said screw it, let’s taxi it around.  The new tailwheel chain tension was much better.  Now it’s more like Mickey’s Citabria, and the ground handling is nice!  I took it to the end of the hangar row, turned right, went down the next row, turned right again, then went back to the barn.  CHT’s never got above 210.   As soon as I get this mag situation sorted out, it’s time for ground runs.

\Last time, shutting off the left Mag made a lot of popping and missing, which I attributed to timing.   This time, I’m pretty sure the timing’s right, but now shutting off the right mag shuts off the engine.  Now, it might have something to do with the fact that I left the pop-rivet I was using for a timing pin in the hole when I pulled the prop through, but I can’t say for sure.   What I do know is that before, on the right mag, I had backfiring.   Now I’ve got squat.

 

Magnetos timed (again) and RPM sensor fixed.

6 hours.

One of the day’s tasks was to replace the magneto gasket we tore with a new one.   This necessitated removing the right magneto, the one that was cranky about timing.   This is also the mag that has the hinky contact spring on one of the harness wires.  I figured what the hell, I’ll make sure both are timed, so I’ll pull both, put new gaskets on both, and set the timing again.   Big mistake.   Timing mags with two people sucks, as you might have gathered from an earlier post.   Doing it on your own sucks too, and then some.   Yesterday it was hot and windy at OXR, so the hangar was warm and the doors were rattling and making freakish noises every couple of minutes.

There are various sources of knowledge as to how to time mags, but the general idea is that you turn the engine over until the crankshaft is at 25 degrees before top dead center.   Then you zero the mag position by sticking a pin in the timing hole in the back of the magneto where it will sink into another timing hole on the gear inside, thus locking the thing into the position where the points are open.  Then you stick the mags back on your timed engine.

A number of factors are at work here.   There’s the impulse couplers, there’s the slop in the mags even with the timing pin inserted, there’s gear lash in the engine itself, and there’s the ambiguity of where 25 degrees BTDC actually is.   Near as I could figure out, there’s a little lump in the rotation of the mag gearshaft where the points open.   This is no great mystery.   A cam inside opens and closes the points to make a spark.  That fires the spark plugs.  This is no different from your common Briggs and Stratton-powered suburban lawnmower.

But the magnetos are buried amongst wiring, hoses, and engine mount tubes, and getting them back on can be extremely frustrating.  The mag gasket is a little wider than the magneto housing, so it’s really easy to dislodge it.   The engine gears of the mags are also wet with engine oil, so they’re slippery.   It’s also of primary, critical importance that nothing falls down the open mag hole into the accessory case.   If that happens, game over.  If that happens, you better hope whatever fell, like a nut or a washer, falls all the way through into the oil sump where it gets stuck to a magnetic plug — if you have one.  The obstacles in the way make it easier, but not by much, to insert the timing pin into the housing with the mags more or less in place, but supporting them, spinning the gear, and inserting the pin is one of the more frustrating solo tasks there are.  The trick is to get both mags installed so they’re within just a few degrees of each other, because there’s only about 70 degrees of twist available to bring them into line.    If they’re too far off, they’ll never sync up.

The next part is relatively easy, assuming the first part goes OK.   This is where the buzz box comes in. This thing has two lights on it, and you connect the leads to the P-lead connections on the mags.  When the points are closed, the lights are on.  When the points are open, the lights are off.   Or vice versa.   Can’t remember.   The point is, the status of those lights is supposed to change when the engine turns through the specified timing mark on the flywheel.   Both mags are supposed to change at the same time.    There’s actually enough wiggle room with the timing pins in the magnetos to put the timing off by a whole gear tooth.  If it’s off in opposite directions on each mag, there might not be enough range to bring them both back into line at the right point.     But eventually, I got it.   The trick is pulling the prop backwards a bit, then advancing to see the lights go.   The prop has to be pulled backwards enough so that going forwards takes out the gear lash well before the points open, otherwise the adjustments are crap.   But you don’t want to go so far back that you catch the impulse couplers again.    Maybe this isn’t the proper way to do it, but this worked for me.  Also of important note: pull the timing pin out of the magneto before cranking the engine around.   If you don’t, best case is you’ll bend your timing pin like a wet noodle.  Worst case is you damage the innards of the mag.

So I got them as close as I possibly could.    Then I put the shielded ground wires back on.   For safety, the shielded wires go back on the P-lead and ground before the distributor caps go on, because until they’re on and grounded, the mag is hot, and if a spark is triggered, it could swing the prop and really ruin your day, especially if you or your stuff is in the prop arc.   Imagine that.  The prop kicks and sends a blade into the tank of your air compressor or a nearby tool cart.   Prop strike!   Have fun tearing down that engine, sunshine.

By the time this process was over, I was already well past my scheduled time to head back to Los Angeles.   But if you’ll remember, this exercise was only part of the day’s activities.   The other things I needed to attend to were the RPM sensor and the oil temperature probe.   Earlier in the week, Matt at MGL responded to my email and said I needed to remove the ballast jumper on the RDAC and that I could delete the resistor between 12v power and sensor signal.   I pulled the ballast jumper, then proceeded to push the ship out into the wind for a quick test.    Ron and Melody helped me push out and get pointed into the Santa Ana wind.   With the wheels chocked, I fired it up, once again.

IMG_1556

It lit right up, after Owen reminded me that I needed to run my boost pump for a second to get some fuel pressure on startup.   It ran strong and smooth, and I had an RPM reading this time, but like a monkey, I forgot to test each mag individually.  But here’s another ground run video:

This time, however, was another milestone.   We pulled the chocks and I actually taxied down to the end of the hangar row, then back.   At that point, my EGT’s were starting to get a little high, so I thought I’d quit while I was ahead.  We pushed it back into the barn and I went home.

Working on engine-start squawks.

7 hours.

Last week’s engine start, while exciting, wasn’t without issues.   The one I thought was going to be most difficult to fix turned out not to be.   The governor operation was reversed, and the fix turned out to be pretty simple.   I just flipped the governor bracket over and mounted it so the cable operates the arm from below.     All I had to do was put a small piece of angle on the side of the arm to secure the #2 fuel injector line.   We’ll have to see about conflict with the cowl.  I put the top cowl on and it looks like there might be about 1/8″ of clearance between the new governor cable arc and the underside of the cowl.  That’s not a huge deal though, and I’d rather put a blister on there than go through the hassle of dismounting the governor and sending it back to American Propeller to see if maybe, just maybe, they can reverse the operation.   Either way, that would cost me in time, in shipping, in ability to test the engine in other ways and debug the two sensor squawks from last time.   The hardest part was the firewall-penetration eyeball.  It’s almost impossible to get to and I still need to torque it down, because it’s not laying flat like it’s supposed to.  I had to take it out so I could get the extra half inch of cable slack necessary for the flipped bracket.

On the others, I had no luck.   No RPM reading, no oil temperature reading, although I have no idea how long it takes the oil to warm up to a minimum of 72 degrees.    The rpm thing is a little scarier because i don’t know if it’s the wiring, the sensor, or the magneto the sensor is attached to.   I’m going to have to break down the wiring of those two pieces and go through it piece by piece.   I really hope the senders aren’t bad, because those things are not cheap.  Replacing both is about a taildragger lesson’s worth.

Speaking of which, I have replaced the ON/ON/(ON) magneto switches with ON/ON DPST  switches.   One side of the switch handles the start circuit and the other handles  the mags.   When the start circuit is enabled, the magnetos are ungrounded.   Since I have two impulse-coupled mags, I can get away with this.   At this point, the starter button on the stick is the only way to kick the engine over now, which is OK, but I plan to install a pushbutton to forcibly engage the starter should the relay the stick button actuates takes a dive.

The magneto timing still needs work.  Even after the switch replacement, the right magneto still makes the engine backfire like mad when it’s on its own.   I’ll need to retime it anyway when I install the new gaskets, but it’s still a royal pain and I’m not keen on doing too many more runs with it in that condition.

Oh, and joy of joys, there’s a small crack in my canopy, in the aft right corner, coming up from the last screw hole on the canopy frame.   I didn’t catch it until now, because it has been  covered with masking tape, which I removed yesterday.   I removed all the protective plastic from the canopy, except for a swatch between the rear canopy and the roll bar brace.   Now the fun is going to be getting that last piece of plastic out from there.  I’ll probably have to dismount the rear canopy, which I would have had to do anyway to get some kind of seal in there.

Engine Start, Part 2.

  1. 5 hours.

Armed with last weekend’s knowledge and suspicion, David and I headed up to OXR to debug and correct the mag and start wiring, then actually start the engine.    We had a copy of The AeroElectric Connection and more importantly, the airport gate card, which allowed us to come and go as we pleased.

Even though we knew what was wrong, it was puzzling, because we were trying to follow Bob’s diagram and make an open circuit for one thing while making a closed circuit for another.   Maddening.

Eventually, we did figure it out and we were rewarded with the sound of an airplane coming to life.

Hooray! Huge milestone, and only three squawks:

  1. No RPM reading.   This is most likely a bad ground or a severed wire coming from the pickup on the magneto.
  2. No Oil Temperature reading.   Maybe this shares a ground with the tach sensor.
  3. (and this is a big one)  Governor operation reversed.   The prop does cycle and the governor doesn’t leak, but it operates the wrong way.   I need to set it up so the prop increases pitch when I pull the blue lever back.

No leaks, no fires, no pieces flying off.   I’d call it a good day!

Engine Start, Part 1.

6 hours.

A tiring and ultimately unsuccessful day.   Dave and I went out to the airport with the intention of starting the engine for the first time.   We were off to a stellar start: I’d forgotten my airport key card; it was still attached to my motorcycle safety vest at home. I didn’t notice it until we were actually in Oxnard, so that sucked.   We did manage to find somebody to let us in, then went about the business of readying the plane for engine start.   We dumped 8 quarts of oil in the tube, then attempted to time the magnetos.    This is harder than it sounds.   Once we actually figured out how to use the buzz box, the cylinder plug, and our own eyes, we got the mags in and timed to the engine.   That’s when the fun started.

We wheeled the plane outside and prepared to start it up.   We left the distributor caps off the mags so we could spin the engine a bit and pre-oil it.   with four plugs removed, we were able to spin the engine around and get oil into all the nooks and crannies and actually see an oil pressure reading come up on the EFIS.      Prop spins, there’s oil, let’s start it!  Foolish us.   Slick magnetos are designed to run when their circuit is open, that is, the two leads connected to them, when connected to each other, make the magneto safe, cold, whatever.   The AeroElectric diagram has you connecting these two switches together in such a way that the right mag fires when you’re starting and the left one doesn’t do squat until the engine’s running, that is, you’ve let go of the spring-loaded upper position toggle because the engine is running.

Somehow, I’d wired it in such a way that the mags were connected/safe when the switches were “on” and the start circuit was on.   The engine spun, but wouldn’t start.   Fortunately, safety wasn’t in question.   The way I had it wired, no matter what position the toggles were in, the mags were grounded, so it’s not like the prop would have taken our faces off.

By the time we’d gotten wind of the problem, it was too late to debug and we were tired.  Tired people working with dangerous things tend to get hurt, so we packed it in and crawled home, after begging to be let out the airport gate.

Equal parts forward and back.

6 hours.

One of these days, I’ll move forward without moving backwards.  Today I had to dismount the EFIS in preparation for taking it to MGL Avionics.   Apparently the OAT module is fried.  I tried it with a new probe last week, no dice.   Maybe, if I’m lucky, I’ll be able to drop it off tomorrow on my lunch hour.   Other than that annoyance, I got the tailwheel hardware primed, something I should have done long ago, and I got my spark plugs torqued in.   But now, for some mysterious reason, the tailwheel steering chains don’t reach their mounting points on the rudder anymore.   It’s possible I had the steering link on upside down/backwards, which would have accounted for the missing 3/4″ of chain necessary to bridge the gap between what I need and what I’ve got.   Looks like I’ll be ordering another set of tailwheel chains.  Grumble.

Anyway, once I get my EFIS back from the shop, it’ll be time to prepare the engine for first start.

On another note, I’m progressing nicely in my tailwheel training.   We flew from Torrance to Hawthorne, where I did 8 landings, unassisted.   Apparently I CAN land a Citabria in 3-point attitude.   At least when the wind is coming at me and I set up the approach right.

Fiddly bits.

8 hours.

So yesterday, I joined EAA 723 at Camarillo airport. I dunno why, but I’m drawn to Camarillo. Maybe it’s because my cousin finished and flew that little hot-rodded Vari-EZE out of there many years ago, maybe it’s because it was the first place I took passengers when I got my private ticket, who knows? But I like Ventura county, and I like KCMA. It also doesn’t hurt that the EAA hangar is right near the Commemorative Air Force hangar, where there are a multitude of interesting flying machines to gawp at. Everyone seems friendly, and the guest speaker for the meeting was an FAA official, who gave us the rundown on ramp checks and a few FAR’s that are very much misinterpreted by the likes of you and I.

The goal of this is to find a nest for my bird where I can final-assemble, certify, and test fly 313TD. Currently, there isn’t any room in either of the hangars, but one gentleman is 20 hours into phase 1 on an RV7A and another is getting ready to go fly, so maybe a spot will open up soon.

Another benefit to membership is that the chapter has a flatbed trailer suitable for moving a project to the hangar, which I will hopefully need very soon. Yet another is several more sets of eyes looking at workmanship and assembly techniques.

As for actual work on the plane, I got the left intercylinder baffle and the replacement fuel pump installed, which is nice. All the wiring is re-secured where it was, and the fittings on the sensor are properly installed with thread seal.

Today, the morning was spent with my neighbor’s vast crew-cab contractor truck, schlepping stuff to and from two different Ikea stores, one in Carson, one in Costa Mesa. We’re doing this kitchen remodel, and our designer was a complete monkey: he ordered a ton of stuff we can’t/didn’t use and failed to get a bunch of things we need, so Shelley and I had to kill our morning putting everything right in preparation for the final cabinet install tomorrow.

I did get some work in on the plane, but it’s cold in Los Angeles right now, down in the 50’s during the day. You East-coasters, Northerners and Midwesterners chuckle all you want, but the little space heater in my shop wasn’t able to take the edge off, so it kind of sucked to be out there today. Cold hands bashing on metal structures when wrenches slip reminds me way too much of college street surgery, changing out a part lying on my back under a car in an icy parking lot. One of the many reasons I moved out here and stayed.

So no, it didn’t go well. First event of the day was an oh-shit moment, when I snapped the head off one of the bolts holding the throttle bracket on. That was a study in anger manangement, and I had the presence of mind to self-soothe through the initial impulses of throwing the torque wrench through the sliding glass door. Tantrums do not fix airplanes.

Fortunately, there’s an O’Reilly Auto store not a city block from my house, so I picked up an EZ-Out (sorry, screw extractor- generic) and through some miracle, managed to get the offending bolt out of the sump. I guess I’m now 1 for 5 using those things. At least I didn’t snap the drill off inside the broken bolt like I did with the wing attach adventure from a couple of years ago.

I installed the breather tube and safety-wired the mixture bracket bolts after torquing them with a different torque wrench (A Snap-On dial-type I bought used) and those are fine. I’m hoping I’m nearly done messing around with Adel clamps. Space is getting tight.