Rubber Heater Core Firewall Grommet Orientation

[Careless]

today, I was about to glue the firewall insulator to the inside of the car i'm restoring, and I noticed that on one of the cars, looking from the engine bay... the rubber insulators that go around the hoses for the heater core have the cone facing outward pointing towards the front of the car. And on another one that i took apart, the cone is facing inward. 

These are the items I'm referring to:

 

does the pictured face of these grommets face the engine bay, or face the interior?

Another photo:

 

Edited March 22, 2017 by Careless

[jfa.series1]

Mine are installed like the second pic and they looked like that when I pulled the car apart for resto.  The normal install for the hoses would be to push them thru from the engine bay.  If the taper were on the engine side, it would have a tendency to fold under as the hose passes thru.

[CanTechZ]

Mine are like this. As far as I know these are original and have never been removed.

Below is the best pic I could find from the 1971 FSM supplement, it's hard to see but to me it looks like the tight fitting end of the grommet is facing out.

 

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[CanTechZ]

Here's a link called L-Series Engine Porn:  https://photos.google.com/share/AF1QipOOstuMLWQ-T-nfkSMbw1tvyAboqyIZEECGlrSo1O7NPbcNEB-Of7X1-LCM-BVavA?key=VXlBaFpISGZBcTl1T1lTcVVuUEVwbWRwMkJPekdn

Shows them installed both ways, but more examples seem to be tight side in the engine bay.  The logic provided by @jfa.series1 does make sense but I like the look of the other way better and I think of the tight side as being a sealing lip to keep dirt, debris & fumes out of the cabin with the lip in that direction.

Edited March 23, 2017 by CanTechZ

[cbuczesk]

I've owned and seen a lot of Zs and all of them have had the cone on the engine side.

Chuck

 

[Careless]

I knew this was gonna be a good debate!

All the points expressed are why I questioned how I had them installed. There are logical advantages to orienting the grommets both ways. 

I just managed to find a set of photos from the tear-down of this particular vehicle that I did not photograph, and low and behold, tucked away in a folder- unbeknownst to me... they were shown like so:

IMHO, it looks way better facing the opposite way, considering the other various grommets don't protrude into the engine bay and i like the tucked in look.

But in keeping with the theme of installing it how it came out; if it seems like it's not wrong and will work how its shown in the tear downs... that's what I'll do.

 

 

Edited March 23, 2017 by Careless

[240dkw]

Here is a pic of mine before restoration. As there was still the cloth wrapped hoses, I am sure they have never been removed. So another vote for taper on the engine bay side. 

[SeafireXV]

An assembly line goof?

[siteunseen]

This was something I would have had to search for soon, I'm about to replace mine. Thanks for the head start.

Here's a 240 I had that was barely touched.  Cones are facing the engine bay too.

[Careless]

I reinstalled them today in the correct orientation. shoving the hoses in did not pose much of a problem. if the lip turned inward, I just tugged on the hose the opposite direction and it corrected itself.

facing the engine bay is how they 'gon stay now.

thanks to all contributors.