Control Cable Firewall Bushing Size?

[tx_jayhawk]

Hi All,

I am installing my control cables (throttle, mixture, etc.) for the last time. The instructions have you put a SB500-6 snap busing in the fuel pump cover that the cable goes through. Although the cable easily fits in that size, the threaded metal portion (that the jam nuts attach to) is bigger than the ID of the specified snap bushing. Going to a larger size would make the cable fairly loose in the bushing.

Have others just slit the bushing or grommet, or done something else? Plans don't seem to address.

Thanks,
Scott
7A

[mayo3808]

Scott
you just need the hole large enough for the threaded part of the cable to go though. you can then add a another bushing inside the first brushing to take up room if you like. But your right there alot of space there.

[pierre smith]

...is Aircraft Spruce's eyeball aluminum grommets:

http://www.aircraftspruce.com/menus/ap/grommets.html

Scroll down to "Eyeball"....something or other..

Best,

[rivetshaver]

I am doing the same thing, I just cut the snap bushing and put it on the cable, now that's on the fuel pump cover, on the fire wall I used rubber grommets and split stainless covers over the grommet on the fwd side.
Greg.

[alpinelakespilot2000]

The outer one does not need to be split, but the inner grommet does--same is true at the firewall.

[ronschreck]

Originally Posted by pierre smith

...is Aircraft Spruce's eyeball aluminum grommets:

http://www.aircraftspruce.com/menus/ap/grommets.html

Scroll down to "Eyeball"....something or other..

Best,

If you go this route, I don't recommend the blue anodized (Model TTP)eyeballs. They look nice and are easy to install, but when it comes time to replace cables I found that the fine threads were galled and I destroyed the eyeball to get them apart. Also, you need to access the back of the firewall to remove these. I replaced them all with the 6-screw type (SE961-S). These are easily disassembled from the front of the firewall.

[dan]

Originally Posted by ronschreck

If you go this route, I don't recommend the blue anodized (Model TTP)eyeballs. They look nice and are easy to install, but when it comes time to replace cables I found that the fine threads were galled and I destroyed the eyeball to get them apart. Also, you need to access the back of the firewall to remove these. I replaced them all with the 6-screw type (SE961-S). These are easily disassembled from the front of the firewall.

I'm a little late to the game here, but I want to echo what Smokey said. I used the one-hole eyeballs on my RV-7, and I am kicking myself. I've had to replace all 3 cables more than once, and I'm currently (this morning) in the process of replacing my mixture cable. Those one-hole eyeballs are such a pain in the fcuk1n6 a$$.

Over time I made a little "wrench" out of 1/8" thick aluminum that lets me hold the base so it doesn't rotate while unscrewing the locking ring, but the locking rings themselves strip. And since one time I had a locking ring vibrate loose on me, I've been using loctite on 'em, which makes matters so much worse when it comes time to remove them. I can't even begin to tell you how much time I've wasted on these stupid things.

All I can say is, the one-hole eyeballs are seriously ANTI easy maintenance. Totally nonstandard, and I will NEVER use them again.

I'm switching to the 6-screw design immediately. I haven't done it yet because switching, in and of itself, is now a pain in the a$$ since my one-holes are pretty close to the engine mount down tube, and the holes are different sizes...I need to make a sandwich plate type thing with bad access. I've been lazy until now, but screw it. I do NOT want to deal with these stupid things anymore.

Hope this helps maybe one builder out there.

[JonJay]

... then follow up with the firewall sealant.

[Brantel]

I second third and fourth Dan's comments...Although I have not suffered with mine as long as Dan has, I hate em none the less!!!!

Originally Posted by dan

I'm a little late to the game here, but I want to echo what Smokey said. I used the one-hole eyeballs on my RV-7, and I am kicking myself. I've had to replace all 3 cables more than once, and I'm currently (this morning) in the process of replacing my mixture cable. Those one-hole eyeballs are such a pain in the fcuk1n6 a$$.

Over time I made a little "wrench" out of 1/8" thick aluminum that lets me hold the base so it doesn't rotate while unscrewing the locking ring, but the locking rings themselves strip. And since one time I had a locking ring vibrate loose on me, I've been using loctite on 'em, which makes matters so much worse when it comes time to remove them. I can't even begin to tell you how much time I've wasted on these stupid things.

All I can say is, the one-hole eyeballs are seriously ANTI easy maintenance. Totally nonstandard, and I will NEVER use them again.

I'm switching to the 6-screw design immediately. I haven't done it yet because switching, in and of itself, is now a pain in the a$$ since my one-holes are pretty close to the engine mount down tube, and the holes are different sizes...I need to make a sandwich plate type thing with bad access. I've been lazy until now, but screw it. I do NOT want to deal with these stupid things anymore.

Hope this helps maybe one builder out there.

[rocketbob]

There are thousands of C-172's flying with the throttle cable penetrating the firewall with nothing more than a hole drilled thru it.