Door Latch Problem

How to keep the Cessna 170 flying and airworthy.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

Post Reply
doug8082a
Posts: 1373
Joined: Tue Apr 23, 2002 2:06 am

Door Latch Problem

Post by doug8082a »

I was at the airport this morning ready to tackle what I thought was a broken door latch spring on the co-pilot's side only to discover that wasn't the problem. :?

Turns out there is a broken component inside the assembly and I'm having trouble identifying the part since the drawing in the IPC (170B pg. 60, Figure 33) does a poor job of illustrating the latch-end of the assembly, which is where my problem is.

When I move the door handle, the Catch - Door Latch (#37 - p/n 0411552) does not move. In fact it just flops around as it no longer appears to be connected to the rest of the latch assembly (aside from the pin that it pivots on). From what I can see the Catch (0411552) is connected to the Strap - Door Latch (#49 - p/n 0411575-6) by a metal strip maybe 3/16 wide x a couple inches long (can't see well enough to tell). This piece is what is broken. I can clearly see the break, I see it move when I operate the door handle, and I can see what appears to be the other end of it attached to the Catch. Question: What the heck is it? I *think* it is #40 - Pull Bar - Door Latch p/n 0411555, but there's no way to tell from the drawing in the IPC.

Does anyone have eny experience with this? Help! My door is DOA.
Doug
zero.one.victor
Posts: 2271
Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

My best advise is to pull the door latch guts out of the door, then you can see what's going on,and match up the ends of the broken piece. You'll probably have to drill out some rivets unless someone has been into there before (which is likely), and reassembled the latch mechanism into the door using screws instead. Which I would recommend you do, if it isn't done already.

Eric
N2865C
Posts: 507
Joined: Sat Oct 18, 2003 9:07 pm

Post by N2865C »

I don't have my IPC handy but I think we are talking about the same part. I recently repaired my broken strap. It is about 10 inches long if I remember correctly (I remember the IPC showing the middle part missing so it looked shorter). We were able to access it through the holes underneath the interior panel and repaired it with a doubler. Someone had cut an additional hole for access sometime in the past that helped. It was tight work, but came out good. I think the price of a new strap from Cessna was about $150.00.

jc
John
N2865C
"The only stupid question is one that wasn't asked"
doug8082a
Posts: 1373
Joined: Tue Apr 23, 2002 2:06 am

Post by doug8082a »

Thanks guys. The part that is broken is NOT the strap. It is the small piece that joins the strap to the catch.

Eric, I think you are right. I'll have to take the assembly out, see what is busted and fabricate a new one.

Oh joy. :roll:
Doug
zero.one.victor
Posts: 2271
Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

Doug, it's not that big a deal to pull the guts out of the door, especially if the rivets have been replaced with screws already. You have to pull the interior panel off the door, then there's several screws (or rivets :x ) to remove at the trailing edge of the door, at the splined interior latch handle shaft,and at the exterior latch handle. Then you have to wiggle the latch assembly out thru the trailing edge of the door. Not too hard to figger out as you go along.

Eric
doug8082a
Posts: 1373
Joined: Tue Apr 23, 2002 2:06 am

Post by doug8082a »

Thanks Eric. I'm sure it's fairly straightforward. I've already got the interior panel off and unfotunately, everything is still held together with rivits, which means I get to drill holes in my brand new paint job. :roll:
Doug
zero.one.victor
Posts: 2271
Joined: Tue Apr 23, 2002 12:11 am

Post by zero.one.victor »

Be careful with that drilling, Doug, or else your brand new paint job won't be looking quite so brand new. :cry:
Post Reply