M20R Gear Rigging to fully retract nose gear

[Ed de C.]

Good evening folks - I just got my new-to-me Ovation home to Michigan yesterday  There are a couple of remaining squawks from the import and annual inspection process done at a NY shop that has Mooney experience but not a ton of it.  The main thing being that the nose gear does not retract fully into the well leaving the doors partially open.  This might explain a part of the 7 - 10 knot speed deficit against book I reported last month.  I'd like to tighten this up.

• The nose wheel is not going all the way up on retraction (which is keeping the nose gear doors slightly open).  Photo’s attached.
• The eccentrics at the rod-end bearing on both “F” tubes are adjusted full up.  2 photos attached.
• Both left and right gear tubes F rod end bearings are turned fully in (short) to get downlock tension within limits. As a mechanical engineer, this is a red flag to me.
• The mechanic tried lengthening the tubes (turning out the rod end bearings):  one turn brings the nose gear up sufficiently to close the doors but the downlock tension falls out on the low side of limits by a significant amount.
• At the other end of the tubes inside the belly the mechanic reports: “I did find that when the MLG actuator was reinstalled that they didn’t properly shim the rod end to the bell crank attachment allowing for interference/contact see attached pictures for details. I have corrected this shimming issue so that the shaft housing is no longer contacting the bell crank housing when gear is fully retracted.”  2 pictures attached.

Our sense is that something is adjusted wrong deeper in the system, causing the nose gear rod end bearing to have to be fully turned in to work.  The mechanic advises we find a Mooney expert that does gear rigging frequently (he doesn’t) and would know where to look for the problem.  We know that at one time the fit was tight based on paint wear on the doors and some wear on the bearing threads.

I've been given a couple of names in Minnesota (Benson at KBBB and Wilmar at KBDH) and of course Don Maxwell.  Unfortunately, Savvy tells me that Don does not work with Savvy and I'd like to keep Savvy in the mix.  I'm in Michigan and would certainly welcome advice as to where to turn to for expert handling of the gear.  I hesitate to throw this at my local shop who sees a few Mooneys now and then.  

Your advice is certainly appreciated.

Best,

Ed

[Ragsf15e]

40 minutes ago, Ed de C. said:

Good evening folks - I just got my new-to-me Ovation home to Michigan yesterday  There are a couple of remaining squawks from the import and annual inspection process done at a NY shop that has Mooney experience but not a ton of it.  The main thing being that the nose gear does not retract fully into the well leaving the doors partially open.  This might explain a part of the 7 - 10 knot speed deficit against book I reported last month.  I'd like to tighten this up.

• The nose wheel is not going all the way up on retraction (which is keeping the nose gear doors slightly open).  Photo’s attached.
• The eccentrics at the rod-end bearing on both “F” tubes are adjusted full up.  2 photos attached.
• Both left and right gear tubes F rod end bearings are turned fully in (short) to get downlock tension within limits. As a mechanical engineer, this is a red flag to me.
• The mechanic tried lengthening the tubes (turning out the rod end bearings):  one turn brings the nose gear up sufficiently to close the doors but the downlock tension falls out on the low side of limits by a significant amount.
• At the other end of the tubes inside the belly the mechanic reports: “I did find that when the MLG actuator was reinstalled that they didn’t properly shim the rod end to the bell crank attachment allowing for interference/contact see attached pictures for details. I have corrected this shimming issue so that the shaft housing is no longer contacting the bell crank housing when gear is fully retracted.”  2 pictures attached.

Our sense is that something is adjusted wrong deeper in the system, causing the nose gear rod end bearing to have to be fully turned in to work.  The mechanic advises we find a Mooney expert that does gear rigging frequently (he doesn’t) and would know where to look for the problem.  We know that at one time the fit was tight based on paint wear on the doors and some wear on the bearing threads.

I've been given a couple of names in Minnesota (Benson at KBBB and Wilmar at KBDH) and of course Don Maxwell.  Unfortunately, Savvy tells me that Don does not work with Savvy and I'd like to keep Savvy in the mix.  I'm in Michigan and would certainly welcome advice as to where to turn to for expert handling of the gear.  I hesitate to throw this at my local shop who sees a few Mooneys now and then.  

Your advice is certainly appreciated.

Best,

Ed

Wilmar has an excellent reputation and sees a lot of Mooneys.  I’d call and talk to them with very specific questions about your situation and try to get a feel for what they think. I have not used them myself though.  I also wouldn’t hesitate to use Dmax for something specific like this without Savvy.  I have used them, and they treated me well.

[GeeBee]

Certainly want to get that cleaned up. It's not bad, but not great. I don't think its worth 7-10 knots. You're going to be down at least 6 knots off of book to start with because of TKS. So 1-4 knots, yeah it might make sense. 

Might talk to Cole Aviation in Dalton, GA. It is an MSC and Joe is really good with Mooney gear. I take mine there every other year for a gear tune up.

[Hank]

3 hours ago, GeeBee said:

Might talk to Cole Aviation in Dalton, GA. It is an MSC and Joe is really good with Mooney gear. I take mine there every other year for a gear tune up.

Joey did great with straightening out my gear after my new IA redid things to his own satisfaction after I specifically asked him not to, because he didn't have rigging boards.

After that experience, I got another new IA. Wish Joey was closer!

[Andy95W]

I don’t have an Ovation Service Manual in front of me, but I’m wondering how your mechanic is checking the nose gear rigging.  On electric gear Mooneys, nose gear down tension is checked by the amount of compression of the nose gear bungee springs, not by using the rigging tool.  That is only used on the mechanical gear Mooneys.  (The main gear is still checked using the rigging tool.)

Your nose gear bungees appear to be fully compressed, which certainly doesn’t seem right (but someone needs to check the actual Service Manual).

There is a Mooney Service Center in Lapeer.  I’m not sure how good that shop is, but they certainly know how to rig the landing gear.

One last thing- gear rigging is only adjusted to set the proper down tension.  It is never adjusted to change the up travel.  That’s a good way to ensure a gear collapse on landing or exiting the runway.  Door rigging fully closed is an art in itself.

Edited September 22, 2023 by Andy95W

[N201MKTurbo]

You have the nose gear rods over extended. The springs should just less than fully compressed at the fully compressed position, which is just shy of going over center. As long as the springs are mostly compressed, you will make the torque spec on the nose gear. Someone at one point thought more was better, that is not necessarily true. This is why the nose gear is not fully retracting.

[skykrawler]

The pre-load checks and rigging procedure are in the maintenance manual.  Should probably get a manual if you are doing things.

[N201MKTurbo]

The rod end on the end of the actuator needs to be extended. The housing should not hit the bellcrank. That won't change anything else, the limit switches are downstream from there and there is enough overtravel in the actuator.

[glenn reynolds]

My ovation is also FIKA and for sure that eats about eight knots of the book speed.  However I REALLY like TKS so no complaints.  I also had a part time mooney mechanic who thought he was supposed to use the older style torque tool on the nose gear and that was wrong.  I learned the hard way that one of my door panel rods was adjusted TOO tight!  yes it sucked up nice, but it eventually broke the hinge.  I disconnected the rod, swung the gear, then tried to fit rod and door and found it an inch too short.  I really believe in doing this at a shop like dmax or wilmar

[warren.huisman]

Highly recommend Oasis in Willmar. I’m also in Michigan and have been getting my J serviced there.


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