Donut Replacement Woes...

[afward]

The plane is down for a separate issue, so I figured I'd replace the MLG donuts yesterday.  We're using the "aircraft weight" method.  The right main appears to align well with the new donuts installed (still need to compress), but the left main is giving us fits...  When removing the retaining screw, we noticed the shaft did not drop as we removed weight like the right side did.  A few firm impacts to the wheel freed it up so we could remove the old donuts.  Trying to put everything back in place, we found that the shaft the donuts are on does not rotate forward enough to align with the hole at the top (hits about 1/4" aft of where it should).  Any ideas on how to address that and/or what the problem is?

I forgot to take photos last night; It was late and I was pretty much "done" when I left.  Hopefully the description is enough...

[Yetti]

Hammer?  Bigger hammer?

[Hank]

This sign was inside the toolbox lid of one of our equipment maintenance guys, at a former job:

Edited December 3, 2020 by Hank

[thinwing]

bolt hole doesnt quite line up....machine a suitible sized "spitser boat tail bullet"than start with tapping to force alighnment followed by bolt or pin to force out bullet

[bob865]

Not sure how exactly it's not lining up, but when we did my nose gear we had to encourage it to move with a large c-clamp to get the holes to align.

[afward]

Unfortunately, it's not the retaining bolt holes not lining up...  I can't get the shaft with the inner bolt holes (and the donuts) to line up with the hole in the bottom of the plate it's supposed to go into.  That said...

If my IA has a large enough c-clamp and we can fashion an appropriate set of spacers, I bet we can get it that way...  I'll have to check with him on that.

[SheryLoewen]

Try it with the new donuts removed to see what the problem is.

Paul Loewen

[afward]

That makes waaaay too much sense...  No wonder we didn't think of it already.

[Guest]

Sometimes when the new discs are installed with the Mooney tool you still have to persuade the swing arm bolts to slip back in.  Gentle prying and persuasion is required, no hammers or beating things is required.

Clarence

[GDGR]

22 minutes ago, M20Doc said:

Sometimes when the new discs are installed with the Mooney tool you still have to persuade the swing arm bolts to slip back in.  Gentle prying and persuasion is required, no hammers or beating things is required.

Clarence

Dog and wife will be happy to hear this, when it comes time to replace the donuts on my F

 

[carusoam]

Go MS!

-a-

[cliffy]

How about taking the swing arm bolts out and sliding the donut shaft in then putting the swing arm bolts back in?

[afward]

Well, we got them on.  Taking the donuts off showed us the parts themselves don't line up quite right (by about 1.25mm, upon closer inspection).  To get it back together we put the donuts back on, lined everything up as well as we could, put pressure on the front of the wheel, then used a large punch & small hammer to tap the shaft into position (coming in from _above_ the plate and placing the punch against the inner surface of the shaft).  Not pretty, but it worked.

We did consider taking out the lower swing arm bolts, but quickly realized that would merely move the alignment problem to a position with less leverage.

Either way, it's now done and I'm excited to see the difference.  Now for the remaining items on the list...

[BKlott]

Would a gear swing be warranted following this maintenance event?

[RLCarter]

3 hours ago, BKlott said:

Would a gear swing be warranted following this maintenance event?

I would and would probably check the over center preloads as well

[afward]

We did a gear swing and everything appeared to be OK.  Didn't check the over-center preloads though.  Not sure how they would be affected...

[RLCarter]

10 minutes ago, afward said:

We did a gear swing and everything appeared to be OK.  Didn't check the over-center preloads though.  Not sure how they would be affected...

It shouldn’t affect it at all, but I have a bad habit of “while I’m here, I might as well” 

[Hank]

1 hour ago, RLCarter said:

It shouldn’t affect it at all, but I have a bad habit of “while I’m here, I might as well” 

While-you're-in-there-itis can become prohibitively expensive!

[PT20J]

On 12/6/2020 at 7:01 AM, RLCarter said:

It shouldn’t affect it at all, but I have a bad habit of “while I’m here, I might as well” 

You're smarter than me  I usually get home and start thinking, "before I closed that up, I should've..."

[RLCarter]

1 hour ago, PT20J said:

You're smarter than me  I usually get home and start thinking, before I closed that up, I should've..."

I’ll fess up, I’ve gone back the next day on more than one occasion for that reason 

[hammdo]

On 12/3/2020 at 4:59 PM, M20Doc said:

Sometimes when the new discs are installed with the Mooney tool you still have to persuade the swing arm bolts to slip back in.  Gentle prying and persuasion is required, no hammers or beating things is required.

Clarence

Just the cussin’ & swearin’ instead...

-Don

[Guest]

8 hours ago, hammdo said:

Just the cussin’ & swearin’ instead...

-Don

Only when used in the correct order.

Clarence

[Hank]

37 minutes ago, M20Doc said:

Only when used in the correct order.

There's a proper order to cuss and swear????? All this time, I've been doing it wrong!

[Guest]

5 hours ago, Hank said:

There's a proper order to cuss and swear????? All this time, I've been doing it wrong!

When used in the wrong order, skinned knuckles may result.

Clarence

[MikeOH]

7 hours ago, M20Doc said:

When used in the wrong order, skinned knuckles may result.

Clarence

Hmm, in my case, the cursing follows the skinned knuckles