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A quite a few years back I inquired about the cut patter in the wheel well of a 180 to install 260 forks. Than never happened. I now have a 250 that I just purchased and I need to install 260 single forks ( along with a complete O/H of the landing gear system. Can some one direct me to or send me the cut pattern in the wheel to accommodate the brake assembly. Thanks, Chic (eritzheimer@gmail.com)
Hi Chic,
I think what you may be asking about is how to cut out the rib in the wheel well to accommodate the inboard brake caliper on the single fork. I have installed single forks on a 180 before. (250 would be the same) We have also moved brake calipers from the outboard side to the inboard side on many Comanches with dual forks.
Anyways, the cut out is pretty simple and is exactly what Piper did on 260’s and later model twins when they went from a dual fork to a single fork in production. I can send you a sample 337 and a drawing. Basically about 3/4 inch x about 5 inches long gets cut out of the rib that is in the top of the wheel well where the caliper will hit. (The same cut pattern that is in a 260, 260B, 260C.). The removed area is to give the caliper clearance so that the gear can go all the way up in the well. It has nothing to do with the fork. And then there is an aluminum angle that is riveted to the rib above the cut out to give it strength.
Also, and some may beg to differ (and FAA FSDO’s will differ) but because the 250 came with a dual fork with a specific part number for the 250, you will need to get a 337 to put a 260 single fork of a different part number on (the 250). Same with cutting out the rib. Ribs are different part numbers, too. It will also require a different gear door/leg bracket. The best thing to do is to have your mechanic confirm with his FAA inspector about if they consider it a major alteration or not. My FSDO here in Chicago does consider it a major alteration. But I had no problem getting the approval. Webco sourced all the parts for us, too.
Cliff Wilewski
Heritage Aero, Inc.
THANKS, PLEASE SEND THE DRAWING...EVEN THOUG i JUST WENT AND TOOK A PICTURE OF A 260...! WGHAT I REALLY NEED IS A DIAGRAM OR GOOD PICTURE OF THE FUEL BOOSTER PUMPS THAT SIT ON THE LOWER RIGHT SIDE OF THE ENGINE COMPARTMENT. THE PARTS MANUEL DOESN'T QUIT SHOW IT THAT WELL.
Hi,
Attached is the description from one of my 337's. It gives the dimensions and location of the cut out. I would actually make the cut out 3/4 high at the forward edge. (*Note that I said "approximately" 1/2 inch in my 337. The stock 260 is about 5/8 inch high. Once you make the cut out. Retract the gear with the brake caliper installed and the wheel removed to make sure there is clearance on both the forward and aft edge of the rib. Also on top of caliper/bottom of rib. It is still very close and sometimes almost touching the bottom of the cut out on the rib. But this is the same as the stock 260's.
Unfortunately I do not have any pictures of the 250 electric fuel pumps and I do not have a 250 in the shop right now.
Cliff Wilewski
Heritage Aero, Inc.
Thank you...!
