Jump to content

My plane has taught me a lot in the last week.


bcg

Recommended Posts

After the electrical failure last week, I figured this was good time to go ahead and do the alternator upgrade since the parts really aren't that much more money and the work has to be done either way.  Fortunately, the A&P I work with is awesome and super accommodating in that they'll let me turn my own wrenches, under supervision, and use some space in their hangar to do the work so the airport manager doesn't get bent out of shape over my working on the apron.  I'm still way down on the wait list for a hangar, it'll probably be at least a couple more years before I can get one.

I ordered the parts Thursday for overnight delivery and started tearing everything down Friday morning. Parts got there early and when I started trying to put the new bracket on, it wasn't fitting like I would have expected. Turns out I ordered the SAL12-70C instead of the SAL12-70 so, I called Aircraft Spruce and got that taken care of with the correct part to show up Monday morning. I come back Monday and everything is going well, I have the bracket installed and the alternator on and while I'm tightening the bolt for the tension bracket behind the flywheel, I suddenly have no resistance. Yep, I broke the bolt. Now the prop has to come off, first time I've ever done that and while it wasn't the worst job in the world, it's definitely tedious backing the bolts out a little at a time over and over again. One of the guys helped me (actually he mostly did it while I watched) extract the bolt, drill and tap the hole and install a helicoil, all of which took about 3 hours. We got lucky, everything went exactly right with that extraction and repair.  I've had a single broken bolt cost me days of blood, sweat and tears in the past so this was a good outcome.  At this point, I realized the voltage regulator that is supposed to be in the kit is missing so another call to AS and I learn that they had several like that, they thought they'd gotten them all off the shelf but, lucky me, I got one that wasn't pulled. So they overnight it and I call it a day.
 
Tuesday I show up a little before noon and the VR is there.  As I read the instructions I realize that this is a much bigger project than I originally thought it would be.  I'd anticipated it being about a 1/2 day swap but, even in the best of circumstances, I think this is a 10 - 12 hour job. I spent the next few hours running all the wires and installing the switch and lamp required by the STC and got everything hooked up except the lamp, which I needed a 1A fuse for and they didn't have in the shop.
 
I've been having intermittent no start issues with the plane the last few weeks that I thought might be related to the starter that was replaced about a month ago so, we started looking into that.  After ruling out the starter, wiring and the solenoid, we isolated the ignition switch as the failure and got another one ordered for delivery on Friday. Holy smokes they're proud of those things.  I didn't want a used one though, buy once, cry once is my theory as I've found it's usually cheaper in the long run to just spend the extra money up front and be done with it.
 
Wednesday, I went ahead and got that 1A fuse installed, replaced the belt with new, put the prop back on, learned how to safety wire bolts, modified the bottom baffle for the alternator and got the bottom and top cowling and the spinner installed.  It doesn't sound like a lot, it took me a little over 5 hours though.
 
Friday, I should be able to replace the ignition switch, I was able to back it out of the dash and pull it through the avionics access panel outside so it should be a fairly easy swap (famous last words).  Then we'll fire it up, adjust the voltage regulator and test everything.  Assuming it all works, I'll reinstall the rest of the cowls and be ready to fly again.
 
I can see now why aviation repairs take as long as they do.  All the little things like safety wire, replacing or installing new wiring, etc. add a lot of time.  It's a lot more tedious and meticulous than working on a car or equipment.  It's all been worth it though, now I know how to R&R the prop in case I ever need to replace the belt away from home or need to send the prop off for repair.  I know everything about my charging system and where all the wires are.  I learned how to remove the G5 so I could pull the panel and get to the ignition switch and I know LOADS more about the wiring in my plane than I did a week ago (although it still looks like a rat's nest).  I'm just more familiar with the plane and it's systems overall now, which can only be a good thing.
 
I wanted to do the work myself more to get it done faster than anything else, they have a week's long wait list like anyone that's any good, and I really appreciate how generous they've been with me.  It's a bonus to get this intimate knowledge of how everything goes together, I feel a lot more confident in the plane now that I've been deep into it.  There were a few other little issues I found while working on it that I repaired, like the exhaust bracket missing a bolt or a broken brace.  I would recommend everyone do something like this at least once.  Even an owner assisted annual would be eye opening if you've never been in the innards of the beast.  I like to know how stuff works though, I think it makes me a better end user.
 
If you're thinking about making the change from a generator to an alternator, let me know.  I'd be happy to walk you through the steps required, it's more than just replacing a bracket and swapping the generator to an alternator.  If I'd known what was involved ahead of time, I think I could have done this a little faster.  It's a big job no matter what though.

PXL_20221026_192715359.jpg

PXL_20221026_192709534.jpg

PXL_20221026_192704264.jpg

PXL_20221026_192700368.jpg

PXL_20221024_160104703.jpg

PXL_20221024_160049076 - edited.jpg

  • Like 3
Link to comment
Share on other sites

Just a thought, but maybe too late now, but some guys attach a spare alternator belt while the prop is off in such a way that if they have to replace the one that is on the airplane (if it breaks or what have you) they don't have to remove the propeller to do so.  Makes it easy to do a field repair when away from home.  Just a thought.  I am not sure exactly how it is done and maybe someone else can chime in here.

Good work though.  I imagine you learned an awful lot about your plane by doing this type of work.  Nicely done.

Link to comment
Share on other sites

Just a thought, but maybe too late now, but some guys attach a spare alternator belt while the prop is off in such a way that if they have to replace the one that is on the airplane (if it breaks or what have you) they don't have to remove the propeller to do so.  Makes it easy to do a field repair when away from home.  Just a thought.  I am not sure exactly how it is done and maybe someone else can chime in here.
Good work though.  I imagine you learned an awful lot about your plane by doing this type of work.  Nicely done.
One of the AP's actually mentioned that to me. He said that by the time the main belt broke though, the backup was usually in such bad shape as to not be trusted either so I elected not to do it. The green belts last a long time, the one I replaced was actually just fine, I just did it anyway since the prop was already off.

Sent from my Pixel 6a using Tapatalk

  • Like 1
Link to comment
Share on other sites

18 minutes ago, bcg said:

One of the AP's actually mentioned that to me. He said that by the time the main belt broke though, the backup was usually in such bad shape as to not be trusted either so I elected not to do it.

It isn’t done to make it a permanent replacement.  It is done so you don’t get stuck and then replace at home base or some other place that is convenient.  

Link to comment
Share on other sites

7 hours ago, bcg said:

He said that by the time the main belt broke though, the backup was usually in such bad shape as to not be trusted either so I elected not to do it. 
 

Wise words from an experienced mechanic. In 25 years of flying I’ve never had a belt fail. I have replaced them on condition and time in service. 10 years of service out of belt on a hangared airplane is not uncommon. No way I want to use one that had been safety wired to the front of my engine for 10 years or even 5 years for that matter.

What kind of ignition switch do you have? They are relatively simple mechanical devices that can be disassembled, cleaned and rebuilt. The starting Contacts in my switch failed about five years ago. The engine would turn over but the shower sparks was not engaging. The engine would fire when I release the key back to both. After disassembling and cleaning thoroughly it’s been fine ever since. 
 

This story very much reminds me of myself as a new Mooney owner in my 20s.  Once you develop an interest in owner maintenance it’s hard to go back. A few instances of high dollar invoices for mediocre maintenance only serve to increase that interest.

  • Like 1
Link to comment
Share on other sites

Wise words from an experienced mechanic. In 25 years of flying I’ve never had a belt fail. I have replaced them on condition and time in service. 10 years of service out of belt on a hangared airplane is not uncommon. No way I want to use one that had been safety wired to the front of my engine for 10 years or even 5 years for that matter.
What kind of ignition switch do you have? They are relatively simple mechanical devices that can be disassembled, cleaned and rebuilt. The starting Contacts and my switch failed about five years ago. The engine would turn over but the shower sparks was not engaging. The engine would fire when I release the key back to both. After disassembling and cleaning thoroughly it’s been fine ever since. 
 
This story very much reminds me of myself as a new Mooney owner in my 20s Once you develop an interest in owner maintenance it’s hard to go back. A few instances of high dollar invoices for mediocre maintenance i’ve only serve to increase that interest.
It's a Bendix.

I'll pull the old one apart and clean it up after I replace it and just keep it as a spare. I've already ordered the new one, might as well install it.

I've done the same with the starter solenoid on my Kubota RTV a couple of times, it's built into the starter so worth cleaning vs buying a new starter, they tend to get some carbon and corrosion on the contacts over time.

I actually enjoy working on stuff so even at 48, this is worthwhile to me. I have already found a couple of things that really should have been caught during the PPI when I bought it in August and have repaired them as I've gone. I always want to trust people but, it's better knowing for sure what's going on under the cowling and what did or didn't get done and why.

Sent from my Pixel 6a using Tapatalk

  • Like 2
Link to comment
Share on other sites

I finished it all up today and got my red dash lights fixed as well. 14.1 volts even at 900RPM, can't beat that. Probably took 35 - 40 hours, all in.

Sent from my Pixel 6a using Tapatalk
 

PXL_20221028_194547328.jpg

  • Like 2
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.