Firewalls

[MikeB]

Or "Who the h--- put that in?"

[Nathan K. Hammond]

Yeah, probably right.

nkh

[DELCOM]

Well I seem to have answered some questions. Looks like I need to find a part # 4-732 firewall tunnel baffle per service helps and hints #26 The Lasher STC that was used for conversion to 85 hp calls for this mod also. I have a new firewall that does not have the ribs stamped in the lower portion where the 4-732 baffle will go,thus easing the attatchment of the baffle. I believe that what I had was an attempt in the past to complete this mod but without installing the needed baffle. All that was done is the lower lip on the firewall was cut back to nill.Service letter drawing S-15 really spells it out. Now...where to get that baffle?
Thanks Del

[Nathan K. Hammond]

You might try ACA. Wag doesn't show it, and I don't think Univair has it either but could be wrong.

It's a fairly simple to make if you're interested in that approach. I did the mod about a month ago and it took me half a Saturday from start to finish. Find a scrap piece of .016 Aluminum and practice bending it around various objects to get the radius you want; or use a slip roller if you've got one. Once you're comfortable bending the Alum. make the real deal. I found once I had the radius, it was necessary to 'pinch' the sides so it fit the firewall better at the edge. Then it's a matter of drilling and riveting. The service letter spells it out very nicely.

nkh

[DELCOM]

Thought that I would try and post a pic again
Thanks Del

[Ron Babos]

Duh, Just looked at service letter 16 plus dwg#15 and now realize what's going on. My plane already has the rounded bottom with no lip. Done quite nicely by someone as to not look out of place. Please ignor my previous stupidity
Ron

[gusc]

Del,

Mine was cut out when it had a short life as a CCM. It now has a small patch on the lower firewall but the lower cowling cutout was not changed back. I didn't even notice it until I read your post.

It cools just fine and keeps all the temps and pressures where they belong.

I have no plan to change anything.

[Paul Agaliotis]

Del,
Check with the Citabria guys. You should be able to adapt a pre 1974 exit piece. Check ACA and Univair. I have one on a damaged Citabria (1965). I,ll see if it can be salvaged.
That looks like a nice 7AC firewall. You may be able to replace it with a previously modified one.
Paul

[DELCOM]

I ordered a wag 416401 firewall with cutout but received a 48602 with no cut out, cant wait to call them and ask why they sent a different part number than I ordered.The one that came is perfect in every way except that it has no cutout.

The only other difference between mine and the one they sent is that the ribs that get stamped into it are not present on the lower portion thus allowing easy mod to cutout and accept baffel # 4-732 I believe what I will be doing is to obtain the correct cut out firewall # 416401 and avoid me doing the cut out, and keep trying to find the correct baffel #4-732 to complete the firewall tunnel mod as indicated in the service letters. If I cant find the baffel

I will consult my IA and see what he would like to see done. I believe what is happining here is they dont list the parts that I need for a 7AC but rather they are listed as for 7ECA,7GCAA,7GCBC,7KCAB,and8KCAB and as Im figuring out the parts are identical shape.

Thanks for all the feedback, and yes this is a great place to just say what your thinking without worring that others going to think less of you if you ask a stupid question.

Thanks All I will keep you posted.

[DELCOM]

Well I talked to Mike at wag and he said that they made a mistake in there catalog and that the 416401 that I ordered is not availible and that it will not be availible in the future.

He went on to say that the 48602 that he sent me is the best suited for the needed mod being that it has no stiffining ridges pressed into it in the area that the baffel should attatch thus easing the installation of the 4-732 tunnel baffel.

He went on to say that they have plans on producing the 4-732 baffel but production is about 4 weeks away. So...I believe that with the firewall that they sent with no ridges and a 4-732 baffel on order I will be able to complete the cooling mod with minimal effort..

Thanks to all for all your input.

Paul, I do not believe that I will be needing you to further check on the used parts that you offered to check on,but THANK YOU for your help.

Things are starting to speed up now on the restoration now that the airframe is done being painted.I will keep you all posted