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B&C alternator installation...

kbalch

Well Known Member
So, I'm working away on my various firewall forward components and have come to the B&C backup alternator (vacuum pad-mounted). It takes up a fair amount of space, though with a little massaging of oil hoses, it'll fit in there nicely. But...

...how the heck does one access the lower left stud to place and tighten the washers and nut? Nevermind actually torquing it, how can it even be started?

Others have done it, so what's the secret? :) I sure hope it doesn't involve removing anything already installed, such as the P-mag...
 
I’ve had it off then on again. A crowfoot on a long extension can be used to tighten and torque it. To get it started I think I had the oil filter off and carefully got it going contortion style. A 10 year old would have an easier time. Or a very petite girl. But I was able to do it myself.

The pmag comes on and off easily enough if you have to pull it don’t sweat it. If you pull the pmag cover the hole dropping anything in that big hole ruins your week.

One thread here suggests using the vacuum pump wrench from ACS. Doesn’t work for this. I tried.
 
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I just reinstalled my vacuum pump B&C backup alternator. The ACS vacuum pump wrench doesn't work due to the geometry difference.

I got the washers and nuts started by shear stubbornness. I worked from the right side of the engine. I used surgical clamps and log needle nose to stab each washer and then the same to get the nut somewhere near the end of the stud. Then I poked my left middle finger in from the back inboard side of the alternator to trap the nut onto the end of the stud. That allowed me to release the tool in my right hand and get that hand above the alternator so another finger from that hand could also touch the nut. Then using both sets of fingers I got the nut aligned and started (eyes on the end of your fingers stuff). I think it took two or three tries with the nut and washers hitting the floor and other things in between.

I tightened it with 1/4 drive Snap-On crowsfoot with slender extension alternating with a double angled open-end wrench. Then torqued it with the crowsfoot using a 0.625" offset for torque calculation (crowsfoot offset). This is one of the times using Snap-On's slimmer tool profiles aid with the tight clearances.

It actually seemed easier than some of the vacuum pumps I have done back in the "good old days".

Jim
 
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Thanks, Jim. Sheer stubbornness I have in abundance. Unfortunately, I also have large hands. I’ll give it a try as you described and then maybe talk my wife into trying it, too. One way or another...
 
I just mounted mine last week. I used long forceps from the left side (more room to get a hand close even though its more narrow opening)and got one finger over the nut and slowly work the the forceps around to start the nut. then it was easy enough the spin the nut down from the left. Moving to the right (its a longer reach but it is a little wider) I slipped a wrench in there and flipped and wiggled and got it snugged up. I used muscle memory to guesstimate the torque.. Hope that helps
 
From my experience working on cars
(disclaimer: I haven't worked on a plane yet)....

Sometimes what looks like more work isn't.


What if you hung the engine from a hoist and loosened/removed some/all engine bolts and moved the engine a bit for access

:confused:
 
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