Removal of gen from acc pad. Nuts are rather hidden - suggestions? Spec Tool?

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docmirror

Touchdown! Greaser!
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My poor generator bit the dust this last flight after ~ 60 years of faithful service. The gen is mounted on the acc case of the E-225 engine and is gear driven off the pad. It's held on with three 1/4' studs with a lock nut on each. The lock nut is in a recess in the flange and is really tight fit. So tight that the get can't be put flush on the pad and have the nuts started on the stud. It has to go on, and come off in stages. Also, on the right side, the oil filter adapter shields access to the nut, and the mag shields access to the top nut.

This is the same gen that I think goes on the back of the O-300 and GO-300 Conti, and maybe even the C-85.

So - hoping that there is a special 7/16" tool, or a special process that will let me get that gen off without removing the mag and the oil adapter housing. One requires the timing to be set again(just done recently), and the other is going to make a nice mess.

If you have made, or know of a tool or special method which will help, let me know. If you think I should just remove the other things in the way - well, really not helping.
 
I put that into Bing search and found something that might be able to get in there but will require some grinding first.

http://www.taiwantrade.com.tw/EP/re...b9c0-3db9-4043-929f-d3526924509c_Wrench20.jpg

I'll need to grind down the top and front so that it will go over the locking crown of the nut but this would be a good start. Now I'm going to try to find one. What would be ideal is a crow foot wrench that has a vertical offset to the 3/8" square drive.
 
Just thinking about it again, I have a 7/16" 12pt offset combo wrench already. I can just start grinding on that until I can get a 1/12th rotation. Once I get it loose enough to spin, I can use a magnetic picker to spin the nut on the shaft. Getting it back on is going to be a hassle, but I think I can get the nut back on with the magnetic picker and rotate it using a bent open end.
 
I kept a box of cheap tools in my shop called "suicide tools". If I needed a special tool I would take one of those and cut/bend it to shape for the job.

Sometimes that's what it takes to get a job done.
 
That sounds like the generator on my C85. Last removal, I had to take on mag off to get the generator on and off.

Ron Wanttaja
 
Yup, I looked at it again and that mag prolly has to come off. Oh well.
 
if it is any comfort, the TSIO-360 isn't much better...and it is supposed to be pulled every 500 hrs to inspect/test the drive coupling. I'm on my third coupling...first one failed within 50 hrs of purchase, second ran about 500 hrs.

Anyway, the alternator is hell since the lock-nuts don't spin off until the last two threads and there isn't much room to swing a wrench.

The only helpful suggestion I have is to pay someone else to RnR the offending generator. Sometimes ya just gotta breakdown and pay the man.
 
Me and the A&P are gonna fight with it on Wed. He's got the timing tools and I want to have a look in the mag anyway. I know we can do it, just time consuming job.

Thanks for the advice. Was hoping for a magic bullet, but it's just wishful thinking!
 
I did this last summer and I couldn't come up with an easy way to get in there for the nuts either. I ended up pulling both magnetos and the vacuum pump off to gain access. Timing the engine is no big deal but getting the nuts back on the vacuum pump is a pain.

I didn't remember the generator nuts being 7/16", I thought they were 1/2". If they are 7/16" you might be able to use a tool similar to the specially bent vacuum pump wrench.
 
Mebee 1/2". Hard to even see in there...
 
One more thing, after removing the magnetos and vacuum pump I didn't need any special tools other than the vacuum pump wrench. Normal box end wrenches and sockets will work fine. I would suggest having a magnet on a stick handy to pick up the washers and nuts you drop though.
 
This is what half-moon and S-wrenches are for.

Dan
 
OK, I went two for three on this deal tonite. I was able to get a little grinding done on a 1/2" combo wrench and get the closed side on the lower bolt and turn it 1/12 and keep turning. No way to get a gear wrench in there. The top one that I though would need to remove the mag was easier. I just ground the shoulder off the open end and got it to turn 1/12 so I could turn and flip, turn and flip...

There's no way to get to the right side bolt in behind the oil pump and filter adapter. If it didn't have a remote oil filter I might be able to get it, but I do, so I can't. I'll take the oil pump off tomorrow and have it out soon after.
 
Got it off, tested no good.

Here's the rub - The effers at Skytronics bought out Jasco alternators in Jan. The price last year for a new alt conversion was $895. Now it's $1025.

grrrrrrrr
 
I did see that. The alt requires their gear drive which is $200 in addition to the alt. It might save a hundred bucks so worth looking into. Also, I don't have to deal with the Skytronics people which is another bonus.

<edit; no STC for my plane for the Plane Power. Jasco(skytronics) has it locked up>
 
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docmirror said:
I did see that. The alt requires their gear drive which is $200 in addition to the alt. It might save a hundred bucks so worth looking into. Also, I don't have to deal with the Skytronics people which is another bonus.

<edit; no STC for my plane for the Plane Power. Jasco(skytronics) has it locked up>
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What model year is your airplane? I thought it fit all the early Bonanzas with the E-225 but I'll admit I didn't look that close.

Another positive thing about the plane power alternator is that it looks smaller than the other options.
 
1950. Not on the STC list. Which is strange.
 
docmirror said:
1950. Not on the STC list. Which is strange.
Click to expand...

It looks like it was listed to me? :dunno:

The way they list it is strange, but all the airplanes on the A-777 type certificate were listed as being eligible.
 
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Aha, I found it under Hawker. My plane is a Hawker now. hmmmmmm.

Might be worth a try.
 
You could have have an auto repair shop rebuild the generator . Or you and your mechanic can do it legally.
 
Vaflier said:
You could have have an auto repair shop rebuild the generator . Or you and your mechanic can do it legally.
Click to expand...

I had it tested. Looks like an open on the armature. I asked the shop about fixing it, and they don't re-wind them, and he can't find it with the shaft for the gear drive. I asked around, and the aero rebuilder has to have a good core, and they charge $495, so for a few bucks more, I can just go with an alt. I really don't want to take the darn thing off again.
 
I went with the Plane power. Put it in this afternoon. Saved some money and some weight. Went in easy, highly recommended. Also lower drag on the engine at all power levels.
 
Well, if anyone cares, job done. Had two bad generators, and one failed voltage reg. Installed the Plane Power alt and it was vundebar. Easy install, good instructions, lower weight, better current and a warrantee. What's not to love.

Getting the old gen out is hellish, but once out the rest went fine. Also found and fixed one fur sure leak, and one other suspected leak.
 
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