Lets talk air clinders for gear doors
#26
+1 Problem solved in less than 5 minutes. I've had a dozen SM airframes and I've only had 1 cylinder that leaked. I've also had cylinders leak in BVM planes. In both cases I used UP cylinders as replacements.
#27
The "new toy" is their large Hawk and Anton is still involved with answering questions with the F-14 and 1/5 F-16.
#28
Thread Starter
Okay guys I went ahead and replaced all the gear doors with UP cylinders, it took all weekend and was super excited till I turned on the jet. Everything went great till I put the gear up and the doors closed, the air started leaking out the air escape port on one of the valves like I was having with the stock. My first thought was the valve itself was bad since it was the same valve as before but when I pinched the line on the non pressure side it stops. I checked the 4 cylinders on that valve by pinching the lines and bam found the bad one, the funny thing is if I pull the door open just a hair it stops leaking. This tells me its leaking around the internal O-ring when its at the end of the stroke(closed). Needless to say im flustered a bit since to replace all these cost of 200.00 so any advice to maybe get that cylinder to function right before I send it back to dreamworks? Is the way im checking it the correct and is my diagnosis correct? I was looking at the cylinders and not sure how they come apart to check the O rings the look pressed on but not sure..... Any thoughts?
Last edited by FenderBean; 05-22-2016 at 03:53 PM.
#29
My Feedback: (360)
Hang in there Fender, I feel your pain : I just spent what seems like an eternity doing the same thing on my latest SM project. Ended up having to replace one of the SM cylinders, and used BVM thin lube to fix another. Finally got it to hold air in the down position, but now the SOB leaked in the up position ! found a leaking TEE finally, and after countless hours, it now holds air for weeks. Was it worth it ? Yep, to me it was. I think alot of guys are happy if it holds air for 30 minutes or so, but not me.
Your trouble shooting methods are the same as I use. Sounds like you just got a bad cylinder. And yes, the UPs are press fit as far as I can tell.Hang in there-you will get it.
-Mike O.
Your trouble shooting methods are the same as I use. Sounds like you just got a bad cylinder. And yes, the UPs are press fit as far as I can tell.Hang in there-you will get it.
-Mike O.
Okay guys I went ahead and replaced all the gear doors with UP cylinders, it took all weekend and was super excited till I turned on the jet. Everything went great till I put the gear up and the doors closed, the air started leaking out the air escape port on one of the valves like I was having with the stock. My first thought was the valve itself was bad since it was the same valve as before but when I pinched the line on the non pressure side it stops. I checked the 4 cylinders on that valve by pinching the lines and bam found the bad one, the funny thing is if I pull the door open just a hair it stops leaking. This tells me its leaking around the internal O-ring when its at the end of the stroke(closed). Needless to say im flustered a bit since to replace all these cost of 200.00 so any advice to maybe get that cylinder to function right before I send it back to dreamworks? Is the way im checking it the correct and is my diagnosis correct? I was looking at the cylinders and not sure how they come apart to check the O rings the look pressed on but not sure..... Any thoughts?
#30
Thread Starter
Thanks I will try some bvm super lube to see if that will stop the leak but if not I will just send it back. This is my second sm project that has been a rough go, I have a third project with issues as well but that's another story for a later time. I will keep at it.
Last edited by FenderBean; 05-22-2016 at 06:05 PM.