Thought some of you might be interested in this one. We just stripped apart the landing gear of a friend's newly acquired 7AC Champ and here's what we found: The new piston at right is the new SAR replacement for the one on the left. The one on the left is a cast piston - the first one I've ever seen, and although the AD concerning the micarta pistons was obviously done, here's what you can still have. Just goes to show you that compressing your landing gear to check whether or not you have aluminum pistons fitted isn't really good enough. I encourage all of you out there who have never stripped their gear totally to do so before going flying again.
Good catch, Dan.
There are a lot of the old parts returning via ebay. It's making the job a little tougher. That is typical of the damage, the weak link is the fiber piston. When the aluminum piston is used the load will find the next weak area. I have found the piston attach pin also distressed.
If the fluid level is maintained in the oleo none of these problems would exist. It's when the oleo slams down on the low fluid level that this damage occurs.
Paul
Mailing Adress : Paul Agaliotis 2060 E. San Martin, San Martin,Calif. 95046
HT,
I haven't had a Tandem oleo open to measure the piston. I do know that the oleo is longer requiring a different spring. But the 7AC oleo will fit in the Tandem case frame so the OD of the oleo is equal.
I believe I have a pre war Chief oleo opened up. I'll measure the piston when I find it.
Paul
Mailing Adress : Paul Agaliotis 2060 E. San Martin, San Martin,Calif. 95046
Paul,
I did a tour of Wag Aero when I picked up my spars a couple of years ago. It appears they have quite a inventory of Safe Air stock and I suspect they're looking for vendors to build products they can't do in house. For example, I believe the spars are built in Minnesota by the same outfit that did them for Safe Air. I know the nose bowls (fiberglass) are built elsewhere. I ordered aluminum fairings for my L16 landing gear and they were back ordered from the vendor.....whoever that may be.
I noticed too that anything that was ' Safe Air' specific still had the SAR number on it. The fuel tank kits are built in house as far as I know as they hold the STC.
Can't tell from your photo......Is the Sar piston drilled for the pin?
How much do they cost?
Do you have SAR's contact/catalog info?
Paul or Dan,
Are these new pistons Identical to ones in L-3s? (1-5/8" diameter, 7/8" high, 7/8" bore)
Thanks,
HT.
This particular piston wasn't drilled for the pin. Whether or not that's standard or not I can't say. It came from Wag-Aero and was very reasonably priced - I believe it was somewhere in the $25 range. They have all of SAR's old inventory and I presume will be continuing to manufacture these parts. The very helpful lady I talked to on the phone says to just quote the Aeronca part number when you call. I'll measure the old piston when I get home next week and will let you know if it'll fit the L-3. The new one was a perfect copy of the original.
Do you (or anyone out there) have the Aeronca part number?
The pistons look exactly like mine.... I'd like to go ahead and order them.... It would be nice to confirm the measurements, first.... if you have the time.