Door Won't Lock After New Factory Seal Installed

[Van Lanier]

Mooney shop installed new factory door seal on my 1963 C model.  Can't fully lock door from inside.  Top pops open.  Tried trimming seal and cutting small holes to compress seal.  No luck.  Any ideas would be welcome.

Many thanks.

[Shadrach]

29 minutes ago, Van Lanier said:

Mooney shop installed new factory door seal on my 1963 C model.  Can't fully lock door from inside.  Top pops open.  Tried trimming seal and cutting small holes to compress seal.  No luck.  Any ideas would be welcome.

Many thanks.

has the plane been stored with the door fully closed for any length of time?
 

My recommendation is to stop trying to correct work that was recently done by a shop that should take responsibility for the malfunction. It should not have been returned to service if it could not be closed from the inside. 
 

[FlySafe]

Hi VL, I had a similar experience after installing a new Knots 2U door seal on my C last year. The problem corrected itself after I let it sit with the door latched for three days in the hangar. However, if I leave the door open in the hangar overnight, the problem can reoccur even 9 months after the installation; ask me how I know. I had to cancel a recent trip. On the positive side, no more air or water leaks, one step forward, 2 back . The other positive is that I am not stuck inside without a door handle and a door that won't open. Good Luck

k

[LANCECASPER]

You can't just install these seals and call it good. They require adjusting while installing since every door is a little different on a handmade airplane. You probably really don't want to pay the amount of hours to a shop that it takes to get it correct.

You do a "rough" install adjusting as you go and then you fly to see where you feel air coming in - some use a light on the ground with one person inside and one person outside, but flying it the sure way to tell if you have a good fit. It usually requires 2-3 flights and some adjusting. That's why the type and amount of sealant is critical. Less sealant is better for adjusting. The inflatable door seals require some shim material in places.

[PT20J]

It took me a few tries to learn how to do this. The placement of the seal on the door is critical. The gap between the door and the fuselage is not uniform. If you use the proper 3M yellow adhesive, there is an hour or so open time to reposition the seal. Don't use too much adhesive -- a thin coat on both surfaces is all you need and be sure to clean the seal and door with denatured alcohol first. After positioning, I close the door on a sheet of printer paper. If the seal is positioned correctly, the door will latch but take some pressure to close and the paper cannot be pulled out without tearing. If it won't shut or the paper is loose you can reposition the seal. If you use the Brown T-9088 seal and shut the door and leave it for a couple of days it will take a set and the door will be much easier to close thereafter and it won't leak.

[DCarlton]

I’m starting to wonder the success rate for these door seal installations.  I spent hours with a mechanic trying to do it years ago and it ended up in the trash …. My door closes now without any pressure, force on the interior handle, or residual pressure on the latch pin.  

[AndreiC]

What type of seal was used? I had an MSC install the Brown T-9088 seal, and it was never right. The door was very hard to close even 6 months after, and there were obvious areas under the door where there were bad leaks (whistling noises while flying). At the recommendation of another MSC (Top Gun) I bought a different seal, presumably the OEM Mooney part - a type that consists of a thin rubber tube with a foam core inside. This worked much better, and only required one adjustment to make it perfect; I did all the installation myself. 

I am not saying that the T-9088 does not work, just that it did not work for me. 

I should add that you can adjust the pin at the top of the fuselage that is grabbed by the latch on the door. It is just a 5/8" nut that needs to be loosened, and then you can screw the pin out a little bit. That may give you some better chance for the latch to grab while the seal is stiff. As the seal molds to the shape of the door, you should adjust it back to where it was, slowly.

[PT20J]

The thin plastic with the foam core was probably BA-189-139. It is softer than the T-9088. But the problem with it is that the foam deteriorates over time and the seal loses its resiliency. Brown Aircraft discontinued it (I called them) and Mooney switched to the T-9088.  The T-9088 works but the positioning is critical.

The bottom is the hardest to get right because there are no latches or pins to hold the door tightly closed, the door hold-open arm is located on the bottom edge, and the curvature of the door frame corners does not match the curvature of the door. I had to remove the right seat and lay inside with the door closed and use a flashlight and a Sharpie to mark the proper location for the seal on the bottom. Along the top and sides, the centerline of the bulb should be placed on the line of rivets fastening the inner and outer door panels together.

EDIT: A trick Don Maxwell uses if there is still an area (usually along the bottom) where the seal isn't tight enough even though it is positioned properly is to cut off a piece of the flat "tail" from a left over piece and glue that under the door seal to shim it a bit. I had to use that in one spot and it worked great.

[Fly Boomer]

On 6/7/2024 at 7:09 PM, Van Lanier said:

Mooney shop installed new factory door seal on my 1963 C model.  Can't fully lock door from inside.

Return to Mooney shop.

[Van Lanier]

Gents, 

Thank you very much for the insights and advice about the door seal.  I'm working the problem.  Apparently, installing a door seal on an old Mooney is more art than science.  

[M20F]

Installing isn’t a super big deal it will take awhile for it to set.  I did mine a year ago and it is almost there.  Then you get a few years and rinse and repeat.  

[FlyboyKC]

I think the real trick is to keep the door closed for a few days. I also found if the hanger is warm (like in the summer heat) the seal becomes more pliable and seems to stretch into place.

I used to have that same problem were could close the door from the outside but it was a real PITA to close it from the inside. Once I started to keep my door closed in the hanger the issue went away. Now its easy to close from the inside.

[jetdriven]

The seal he has has the Mooney part number on it and it came from Mooney. And it is, indeed a genuine BA1706 – M style seal. The triangle shaped thin rubber seal with the foam core. I haven’t seen one in several years. But anyway, the seal holds the door open about a millimeter further than will allow that upper latch hook to grab the in inside the door. This is not the adjustable pin with the alligator jaw that grabs it like you see in later airplanes this is an older plane.

[Jim Peace]

Same with my 64c. Door needs to be closed in the hangar and all other times as well. Took about 3-5 months for it to compress. Same with the baggage door.