8 Zircs per main gear; I don't believe you ;)

[TheTurtle]

I went out to the bird to try to track down the elusive 8 zircs per main gear.  I can only find 6.  Can somebody give me a hint on where the other 2 are?

Since I havent found pics of the zircs on this site I figured I would start a gallery on how to find your zircs.  Ill do the nose after I find that last 2 on the main.

I circled with question marks the only places I thought there should be a zirc but couldnt find one or even a hole where one should be.  

My #4 zirc is missing.  Ive replaced it once but looks like it got yanked out at annual again.

 

[lamont337]

The fitting for your forward trunion is definitely gone. I had to use a small Allen wrench to remove the remainder of mine. It unscrewed easily, just needed to get something in there.

[Hank]

Good luck! Thsre really are 8 on each main gear, and 11 on the nose gear. Look where there are joints or rotating motion.

When I'm greasing the gear, I find, clean and count all of them on each leg, then recount them as I grease from the top down towards myself on the creeper.

[carusoam]

@TheTurtle

I think Lamont has part of your answer!

Hank gave the logic of how/where to look for the others...

The method that some zerks use to hold themselves in place isn’t enough sometimes....

Finding a proper replacement may be as easy as calling Lasar or spruce...

Best regards,

-a-

[TheTurtle]

1 minute ago, carusoam said:

@TheTurtle

I think Lamont has part of your answer!

Hank gave the logic of how/where to look for the others...

The method that some zerks use to hold themselves in place isn’t enough sometimes....

Finding a proper replacement may be as easy as calling Lasar or spruce...

Best regards,

-a-

I got a bunch of new press in and screw in from lasar.  Now just trying to find all the holes!!

[TheTurtle]

25 minutes ago, lamont337 said:

The fitting for your forward trunion is definitely gone. I had to use a small Allen wrench to remove the remainder of mine. It unscrewed easily, just needed to get something in there.

Awesome.  I should have seen that one.  One more to go!!

[skydvrboy]

I'm just impressed with the life you've gotten out of those shock disks.  The date codes are indicate they were made in August of 1966.  I thought the ones I replaced from 1976 were old!

[M20F-1968]

8 hours ago, skydvrboy said:

I'm just impressed with the life you've gotten out of those shock disks.  The date codes are indicate they were made in August of 1966.  I thought the ones I replaced from 1976 were old!

They are worth replacing.  Look pretty much compressed.  Landings will be much better after replacement.

John Breda

[mike_elliott]

8 hours ago, skydvrboy said:

I'm just impressed with the life you've gotten out of those shock disks.  The date codes are indicate they were made in August of 1966.  I thought the ones I replaced from 1976 were old!

I think you may be looking at the part number

[skydvrboy]

15 hours ago, TheTurtle said:

@mike_elliott  I've made that mistake once before thinking the disks were made in 68 (since there is a 1968 in the part number).  However, this picture clearly shows the date codes on the bottom and third disk (08-66).  I'm not saying they need changed, that would be determined by measuring the gap under the collar at the top.  I assume this is  being checked at each annual, so am impressed they have lasted so long.

[LANCECASPER]

I would change the shock discs and put new brake lines on it. I had PHT make two new brake lines for mine and it was just over $100 each. When I got the old ones off it was scary that I had been counting on those to deliver fluid to my brakes. From the outside they looked a little ratty but they were very brittle.

Here's what a new shock disc looks like:

Your IA is not doing you any favors signing off on the old ones every year. They are 53 years old and have no elasticity left. Your airframe is now absorbing all of the shock. You will notice a world of difference in just taxiing the airplane after the shock discs are changed.

[TheTurtle]

3 hours ago, M20F-1968 said:

They are worth replacing.  Look pretty much compressed.  Landings will be much better after replacement.

John Breda

I'm not sure that's possible.  They are so buttery smooth now they cant get much better 

53 minutes ago, skydvrboy said:

@mike_elliott  I've made that mistake once before thinking the disks were made in 68 (since there is a 1968 in the part number).  However, this picture clearly shows the date codes on the bottom and third disk (08-66).  I'm not saying they need changed, that would be determined by measuring the gap under the collar at the top.  I assume this is  being checked at each annual, so am impressed they have lasted so long.

I have to go through my log books.  I would swear they were changed in the 90's sometime.  Maybe that was just the nose.

Cant get anything by you guys!!

[TheTurtle]

31 minutes ago, LANCECASPER said:

I would change the shock discs and put new brake lines on it. I had PHT make two new brake lines for mine and it was just over $100 each. When I got the old ones off it was scary that I had been counting on those to deliver fluid to my brakes. From the outside they looked a little ratty but they were very brittle.

Here's what a new shock disc looks like:

Your IA is not doing you any favors signing off on the old ones every year. They are 53 years old and have no elasticity left. Your airframe is now absorbing all of the shock. You will notice a world of difference in just taxiing the airplane after the shock discs are changed.

I actually have a set of pucks for the mains.  Just havent put them on.  Came with the plane.  I have the tool as well..

I replaced the brake lines when  I bought it.  They are only 3 years old.

[LANCECASPER]

Just now, TheTurtle said:

I actually have a set of pucks for the mains.  Just havent put them on.  Came with the plane.  I have the tool as well..

I replaced the brake lines when  I bought it.  They are only 3 years old.

They have a five year shelf life.

[TheTurtle]

Just now, LANCECASPER said:

They have a five year shelf life.

lol this set lasted 53 years...  IO360 has TBO of 12 years.  Im going to call them  good at $200 each.

[LANCECASPER]

6 minutes ago, TheTurtle said:

lol this set lasted 53 years...  IO360 has TBO of 12 years.  Im going to call them  good at $200 each.

I wish the new ones lasted as long as the old ones - somewhere along the line the formulation changed.

They may have been on the airplane 53 years but they definitely didn't last 53 years. Just like the original oil may still be in the crankcase of a 53 year old car, but I wouldn't be proud of that and use it as a selling feature.

They're $110.58 each

[Guest]

To fund the replacement you could sell the old ones to the NHL for use as hockey pucks.

Clarence

[skydvrboy]

2 hours ago, LANCECASPER said:

You will notice a world of difference in just taxiing the airplane after the shock discs are changed.

I second that.  Before changing them every bump was felt as a jolt as I taxied along.  Now every bump is felt as a bounce, like the plane is on springs or a big rubber bouncy ball.

[jaylw314]

1 hour ago, M20Doc said:

To fund the replacement you could sell the old ones to the NHL for use as hockey pucks.

Clarence

I think the one souvenir puck I have signed by Wayne Gretzky cost just about as much 

[kortopates]

I actually have a set of pucks for the mains.  Just havent put them on.  Came with the plane.  I have the tool as well.. I replaced the brake lines when  I bought it.  They are only 3 years old.

 

The good news is you'll only need the special tool for the nose. The weight off the plane on the mains should be enough to compress the new main disks. Do a good inspection looking down inside the top of the shock link tower - it's often corroded. LASAR sells a less expensive PMA'd part. After 53 yes I'd expect to need some new bearings too. (Not expensive)

 

Sent from my iPhone using Tapatalk

 

[DXB]

1 hour ago, skydvrboy said:

I second that.  Before changing them every bump was felt as a jolt as I taxied along.  Now every bump is felt as a bounce, like the plane is on springs or a big rubber bouncy ball.

I was just about to say the same thing.  I'm not sure which I like less.  The oscillation makes me cringe, thinking a prop strike is imminent.  These are not sophisticated suspension systems.  

[TheTurtle]

Was able to replace one press in zirc.  Theres 2 that still have some remains of the broken off one.  My pick bends trying to get the pieces out so need to go find a different tool that won't break or leave shavings behind if I drill them.

More importantly.  Wheres that 8th zirc!!!! Arggh

[jaylw314]

48 minutes ago, DXB said:

I was just about to say the same thing.  I'm not sure which I like less.  The oscillation makes me cringe, thinking a prop strike is imminent.  These are not sophisticated suspension systems.  

You just have to tap on the brakes in time with the bounces.   Of course, if you get it wrong...

I'm just kidding of course, don't try to do that. 

[mike_elliott]

7 hours ago, skydvrboy said:

@mike_elliott  I've made that mistake once before thinking the disks were made in 68 (since there is a 1968 in the part number).  However, this picture clearly shows the date codes on the bottom and third disk (08-66).  I'm not saying they need changed, that would be determined by measuring the gap under the collar at the top.  I assume this is  being checked at each annual, so am impressed they have lasted so long.

Zooming in I see you are right. New President nominee for CB club!

[Hank]

Hold on, zirk photos coming. Need to edit on a larger screen 

P S.-- Yes, it's 8 and 11.

Edited April 15, 2019 by Hank