Mag Removal- Bendix

[Tom Mc]

I just bought  my 1962 M20C and now I am starting to get it mechanically up to where i want it.

500 hr mag inspection is due.  Left mag removal - looks like the Vac pump and the battery box need to be removed first.

Any thought on access? Wow this look tight!

And how to get to the oil sump screen? Crazy!

Any advice on accessing these items?

 

[N201MKTurbo]

Welcome to working on Mooneys!

[47U]

57 minutes ago, Tom Mc said:

Any advice on accessing these items?

You should be able to get the left mag off without removing the vacuum pump.  You might be able to reach the battery box hardware with your right hand by reaching in through the avionics access panel on the pilot’s side (depending on how ‘clean’ your wiring harnesses installation/routing are).  The battery box hardware on the firewall side can be reached with your left hand.  I can remove my battery box in about 10 minutes.  Consider a SureFly for the left mag and you won’t have to mess with it again.

The suction screen is what it is.  You might have better luck reaching down from the top before you reinstall the oil filter.  The support bracket for the throttle cable might be in the way.  The fuel line from the footwell to the fuel pump might be in the way.  But, with perseverance, the sump screen can (AND SHOULD) be removed, inspected, cleaned, and reinstalled at every oil change.

[Tom Mc]

Thanks- I am also doing a Alt (ALY-8520LS replacement and Zeftronics R15300   regulator replacement.

When I get my Alt/Reg I'll start the process next week.  The BTM cowl will be difficult (R&R) on the ramp alone.... any hints of this process?

You top down idea will require a step ladder/stool of sorts. 

[Hank]

2 hours ago, Tom Mc said:

You top down idea will require a step ladder/stool of sorts. 

I use the stool on every oil change. Walmart has inexpensive ones. Get 3 steps, and don't stand on the top step.

The left mag is a pain. The four screws on my battery box are a pain, they are under the carpet in the front footwell. I unhook and remove the battery first.

Just be aware that the many previous owners may not have put everything back together exactly how the factory did it. My battery box bolts went in from both sides rather than all four from the cabin through the firewall.

Prepare to use several tools, seems I needed wrenches and a screwdriver. Plan on several sizes.

Don't forget a clean rag to stuff in the hole after removing the mag.

NOTE:  the left magneto can be removed from the engine without moving the battery box. I messed with it for almost an hour, it won't come out that way . . . .

Enjoy your about-to-be-enhanced new vocabulary!!

[Tom Mc]

Oh, so I pull off the access panels top side in front of the windscreen to access the bolts...  I am not at the airplane now, and I am new to working on old Mooney's.

Those LH  avionics access panels will give me access to the Battery box hardware?

[Hank]

16 minutes ago, Tom Mc said:

Oh, so I pull off the access panels top side in front of the windscreen to access the bolts...  I am not at the airplane now, and I am new to working on old Mooney's.

Those LH  avionics access panels will give me access to the Battery box hardware?

Battery box is under the cowl.

[Tom Mc]

Right- but it sounds like some of the battery box mounting hardware is thru the firewall...?

I'll see the airplane again next week to confirm- but if there is hardware thru the firewall accessing it would be thru the avionics access panels.

[Hank]

1 minute ago, Tom Mc said:

Right- but it sounds like some of the battery box mounting hardware is thru the firewall...?

I'll see the airplane again next week to confirm- but if there is hardware thru the firewall accessing it would be thru the avionics access panels.

Yes, the battery box is attached through the firewall, but it's mounted to the engine-side of the firewall.

Remove top cowl, remove battery, unbolt and remove battery box (through avionics panel or a second person standing on their head under the panel),  remove magneto, stuff rag into hole on rear of engine.

[47U]

3 hours ago, Tom Mc said:

Those LH  avionics access panels will give me access to the Battery box hardware?

The two forward battery box mount bolts are in the footwell, above the rudder pedals.  The back two on the firewall.  Removing the rear outboard bolt, I get bloody from the tail of the wire pigtail on the parking brake valve.  

My bolts were installed with the heads forward, so that’s how I always reinstalled them.  But, it sounds like @Hank has his the nuts forward.  That might be way easier, putting the nuts on where you can see the threads of the bolts.  

This is all contingent on you being able to get your right arm down deep (like, up to your armpit) through access panel, avoiding the wire bundles (if there are bundles and not just loose wires running every which way), vacuum hoses, etc… 

[Hank]

25 minutes ago, 47U said:

My bolts were installed with the heads forward, so that’s how I always reinstalled them.  But, it sounds like @Hank has his the nuts forward.  That might be way easier, putting the nuts on where you can see the threads of the bolts.  

This is all contingent on you being able to get your right arm down deep (like, up to your armpit) through access panel, avoiding the wire bundles (if there are bundles and not just loose wires running every which way), vacuum hoses, etc… 

Some of my bolts went each direction, removing them was an exercise in frustration. I think we reinstalled them with nuts on the firewall rather than under the carpet inside.

Having the 201 windshield with small avionics access panels, I had a friend use a wrench under the battery box, and I stood on my head and crawled into the pilot footwell. . . .

[Matthew P]

During your next annual, when you have the interior panels out, and relocate the battery to back to get you some working space...you have to access the screen from the right side...hopefully you have small hands or your wife does and doesn't mind helping