PA18 Continental engine cowling.

[FlatSideShovel]

Does anyone know the location of the engine cowl brackets on an original Continental powered PA18. The firewall on a PA18 and a PA11 are the same but the engine cowls are not. As we know, the PA18 used a swing out engine mount and the PA11 used a fixed mount, because of this the PA18 cowl has to be longer than the PA11 to accommodate the longer engine mount. Are the locations for the cowl brackets angles on the firewall the same as on a PA11? I suspect that the same location is used and that a PA18 Continental engine cowling should fit. I have the Northland CD but all it has is are the drawings for the Lycoming Powered PA18's. I have talked to Univair but they are hesitant to give me the details on exact dimensions and they will not supply drawings.
Thanks, Flatside

 

[Steve Pierce]

The cowl attach brackets on the firewall of the PA11 and PA18 are the same. I wasn't aware that the cowls were different. I worked on a PA11 that had the swing out mount and didn't notice any difference in the cowling but it was several years ago. I do know that the boot cowl is the same (PA11 and PA18-95 same part number) because I got the last old stock Piper boot cowl from Univair some 20 years ago and it had the windshield strip and the cowl brackets already attached and they fit perfectly.

 

[mike mcs repair]

don't know,

but i saw a couple different firewall blueprints at http://www.supercubproject.com/drawings/

 

[wireweinie]

Northland CD, diagram #12365. Shows where to locate/drill the holes to attach the brackets. Will that work for you?

Web

 

[MainlandCub]

I believe the attached drawing is for the PA-18-95 / PA-11 firewall. I don't have the PA-18-95 boot cowl drawing, so can't fully confirm the P/N, maybe someone like Steve can.

I have 12365 open beside 10792 and the 10792 is shorter and narrower and the distance between the engine mount holes is the same, so it is highly likely this is the right drawing.

I can't claim any credit for this drawing as I think it came from this site. Another file I have has PA-11 in the title; might be the file title as it was when lifted from this site.

I hope that helps,
Andrew.

 

[Dbow]

I have a firewall from a PA18-95 in my hanger and could make a template if you still need this.

Dennis

 

[FlatSideShovel]

If its a used firewall it would help to measure between the top angle bracket attach points on the firewall, the actual 2 screw holes that secure the angle bracket to the firewall. These are the brackets that hold the engine cowl rails going forward to the nose bowl. If it is a new firewall these angle bracket are not part of it and must be fit and attached along with the sheet metal doublers as shown on drawing 10792. The exact spacing of these angle brackets is not shown in drawing 10792 and the only way to be sure is to have a PA18 (95) top cowl to measure.
Harry

 

[Dbow]

I have a used firewall in good condition and will get back to you on Friday with those dimensions.

 

[fancypants]

My firewall is bare at the moment, so it was easy to measure. The holes are a little wallowed. The measurements are approximate, but should be close enough.

image 1 - top hole cowl attach center-to-center: 17"
image 2 - bottom hole cowl attach center-to-center: 16-9/16"
image 3L - top hole center to top of firewall: 5/16"
image 3R - bottom hole center to top of firewall: 1-1/16"
image 4 - cowl attach angle center-to-center: 3/4"

We'll see if I can remember to measure the bottom brackets tomorrow.

 

[Steve Pierce]

This copy of the drawing blows up better and has the dimensions for the cowl rail attach channels that mike has measured.

 

[fancypants]

Hmm, I think the forum software is compressing the PDF and degrading the quality. Both Steve and MainlandCub's attachments are the same size and both are hard to read. If you go directly to http://www.supercubproject.com/drawings/main.aspx and enter 10792, you can download the full resolution PDF which is much easier to read. I also attached it here as a PNG, which might not be compressed like the PDF.



edit: Nope, even the png gets compressed beyond usability. bummer. I guess you just have to download it directly from supercubproject.com