Disconnecting Controls

How to keep the Cessna 170 flying and airworthy.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

Post Reply
User avatar
gobrien
Posts: 113
Joined: Sun May 19, 2019 11:36 am

Disconnecting Controls

Post by gobrien »

This is a general question rather than 170-specific:

Can anyone tell me how to get the throttle, carb heat etc. controls out of the panel without wrecking them?
Controls Collage.jpg
I got the primer out and the mixture control. The engine-side attachments on the rest are all too large to go through the firewall. Do they have to come off or is there a way to detatch the knob and feed them back from the cabin side?

All help appreciated!

Gareth.
1948 170 Project (N4180V) now EI-AEN SN:18513 - Dublin, Ireland
https://www.taildragger.eu/
User avatar
gobrien
Posts: 113
Joined: Sun May 19, 2019 11:36 am

Re: Disconnecting Controls

Post by gobrien »

For anyone that happens across this in a search, I figured it out (at least it worked for me):

1. Remove everything engine-side so the wire can slide up the inside of the sheath and out.
2. Release the control front and back of the panel
3. Pull the control into the cabin catching the rear retaining nut and any washers as they try to fall into the open inspection holes!

Exception:
On mine the carb heat had a spring loaded control with a ball bearing in it. You release the knurled nut, compress the spring to release the knob and and GENTLY pull the control out of the sheath. CATCH THE BALL BEARING. (I didn't and now have to source a replacement). Then pull the control wires out of the sheaths into the cabin through the panel.
1948 170 Project (N4180V) now EI-AEN SN:18513 - Dublin, Ireland
https://www.taildragger.eu/
User avatar
wabuchanan
Posts: 147
Joined: Sun Nov 02, 2014 2:51 am

Re: Disconnecting Controls

Post by wabuchanan »

The Stock throttle cable end is a threaded piece that is unscrewed from the cable. That will leave you with no obstructions to coming through the firewall. You need to remove the grommet from the firewall and it should pull through. The Grommet is a tight friction fit. Put a new one in with a new cable or putting the old cable back in.

Mixture should not be a problem, it is just the end of the cable and the internal wire. Easy to back through he firewall into the cabin.

Carb heat on mine was also just the cable end once I unclamped it from the lever arm and it came out easily, although the fitting in the firewall needed to be manipulated a bit as it is meant to hold the cable from slipping.

I've not done the primer or tach cable yet so no experience with those.
1950 170A N5776C SN:19730
User avatar
n2582d
Posts: 2808
Joined: Mon Apr 29, 2002 4:58 am

Re: Disconnecting Controls

Post by n2582d »

Gareth,
Don’t reinstall the cables in the holes they were in. Check out Fig. 17 and Fig. 34 of the ‘48 IPC. I haven’t compared cable routing of the ‘48 with the later models but the way your cables were routed doesn’t match the IPC at all. Maybe someone with a ‘48 could post a couple of pictures of their firewall?
Gary
Post Reply