PA32 Strut Woes
I’m having a rough time getting to the bottom of this problem and it’s getting quite frustrating. The passenger side main gear strut has been giving us issues for over a year now. We’ve had to have to strut rebuilt about 3-4 times. The first A&P replaced the lower seals to the tune of $250 each time and it was always a bandaid. The problem would return a month or so later. It would slowly start to sag and eventually go flat. We bought a nitrogen bottle and apparatus to fill up the strut ourselves but it’s a bit of a pain to do so often.
We recently had an annual and told a new A&P about the problem. They removed the strut from the plane and replaced the lower and upper seals to the tune of about $2k. We were assured this would solve our problems. Two months and six flights later the strut is flat again. This time completely flat all of a sudden and I’ve got fluid leaking out of it. Seems like a more involved failure.
The previous A&P suspected a former owner may have used scotchbrite pads to remove rust or corrosion from the tube. What are our options here? Can we pull the assembly apart and have the tube machined? Or is there something else entirely that we should be focusing on?
Comments
Rather than just changing a seal here or there, I'd do a full reseal on the strut. A kit is ~$40, and it should not take 20 hours to pull, reseal, install and service. Should be able to do the job in a day. If, while broken down for the reseal, they find damage in the piston chrome you can find options. I don't know of any shops that rechrome, but you may be able to find one. Other option would be a replacement, and I'm sure that would be not cheap.
Tom Jackson
PA28RT-201, N3022U
Tappahannock, VA (KXSA)
A&P/IA, Private Pilot, IR/A
Did they put soapy water over and around the filler valve and/or replace the filler valve? I had a sneaky leak there that kept me going.
Regards,
Mike
Loyola;
If it's leaking fluid, it's definitely a seal (or the wrong seals were installed) or as your former A&P mentioned, the strut itself has been compromised. Could be a hairline crack, a gouge caused by sanding, etc. Many machine shops or automotive engine rebuilders can magnaflux or penetrive dye test the strut to check for hairline cracks. Could also that the strut is simply worn out and out of tolerance.
Make sure the Schraeder valve is tested as well as the seals around the valve.
Agree with Tom_jax, get the full seal kit replaced, but first find out why it's leaking down.
Jim "Doc Griff" Griffin
PA28 - 161
Chicago area
It sounds like you got more of a air leak problem than you do a fluid issue. It probably would be worth doing a die penetrant inspection on the complete housing to make sure you don't have a crack but of course you have to take the whole thing out to do that. If the chrome strut is worn it might be possible to have it rechromed I know I've seen it done in the past it's not very common. One of our fleet warriors made your problem look simple with the amount of flatness we had to put up with on that thing but it has 17,000 hours on it I think we eventually bought a used chrome strut for it and that slowed the problems down at minimum.
How many hours on the air frame?. It's possible if it's high time your whole complete outer housing is just worn enough to allow too much slop and while new seals work shortly they can't make up for the excess clearances.
Carl
48 yrs A/P IA DAL aircraft inspector. 172N
Back in the mid 90’s Piper came out with an AD that replaced both struts on my Seneca with a beefed up strut. The reason was the original struts were developing cracks. I seem to remember the new struts were $1,000 a piece. You might want to check if that AD applies to the PA-32 since your airframe and the PA-34 airframe are similar.
John O’Leary
Turbo Arrow IV (KRKP)
CFI CFII CFIMEI (Gold Seal), ATP(MEL)
Wright Bros. Master Pilot
Fixed gear or retract? What year and Model?
First, which Year make and Model and how many hours on the aircraft.
Second, see if SB 1131A applies to your aircraft.
Third, if its fixed gear, you’re not going to like the answer.
I have the same problem on my 1966 PA-28-180 and have done the same thing. You have the cylinder (I call barrel) and you have the Oleo (I call strut). Currently, I have the right gear off my aircraft for the same reason. Inspecting the barrel we could find nothing out of the ordinary but since we got a newer (there are no new cast barrels or struts for these aircraft) for the left gear, which it seems to be working and I wont jinks it further with discussion after being rebuilt, we got one for the right side as well.
However, after ordering a replacement barrel for the right side, upon closer inspection, we found a vertical scrape/groove/whatever cut into the strut. After discussing it with the guy in Florida (who’s been doing Pipers for longer than Ive been in diapers) he said that scrape/groove whatever cut into the strut indicates it’s bent. You can’t really see it, but it’s there. THATS WHY THESE STRUTS FOR THE RIGHT SIDE CANT EASILY BE FOUND!
Pilots on Pipers, especially students, land these things wrong a lot of times and that’s when it evidently happens.
When this is done and it works fine, I’m selling my PA-28, mainly for this reason.
Don’t expect MacFarlane or any one else to come out with a fix. This gender of aircraft has had its day and parts are hard to come by.
James Javurek
ATP/CFI/AHI/ AP/IA
One more thing, brand new seal and scraper ring was installed. After inspecting the scraper ring (which has a manufactured split in it) it was not lining up symmetrically. Running your finger on the inside of the ring would catch your finger/fingernail and under pressure looks like it would cut into the strut, which leads me to believe what the guy in Florida was telling me.
FYI.