Well in continuing going thru' all the possible leak points I did find that this cylinder for slide cover was leaking really good at shaft seal. I decided to remove it from coach and with my Pit this job was made easy. In 30 mins I had it all out only to find that this stainless cylinder has no markings etc on it.It cannot come aprt as ends are pressed on and crimped. I have measured it all up to try a google search befroe calling FOT. I did pump some synthetic grease into fittings and that has cut the leak down drastically-so I put it all back while I do the searching.
I believe FOT mechanics call this removal almost impossible location to get too but it was no trouble with being able to stand under it!!
Has anyone ever replaced the cylinder and if so who sells them etc. It is not an Economair type as the drop down step.
Total length 24.5" Dia of bore 1.375" and stroke around 22" with 0.437" shaft
I have now had 50% of lines off and most check valves and protection valves to clean out or replace. Air is holding up pretty good now at 115psi for a couple of days. Front tank does drift down more than rear so am concentrating on that system more.
Thanks
John H
Had my step cover cylinder replaced, it leaked much more when retracted, not so much extended. MOT replaced it, do not recall the cost of parts or labor. Gave the old one to guy workingfor me, he is a tinker, who knows what contraption he rigged up with it.
Sure am happy for your pit.
Dave M
Yes Dave- Mine was leaking the same way-when retracted. They look like a cheap cylinder and no markings what so ever-strange.
John H
Howdy John,
MOT replaced my leaking retracted cylinder several years ago.
P/N on the invoice is listed: D55415A215
Good Luck, Dave A
An interesting article on how to determine the force of cylinders: How to Calculate Pneumatic Cylinder Force | eHow (http://www.ehow.com/how_4897627_calculate-pneumatic-cylinder-force.html)
Thanks Dave, will google it but may be a FOT #.
What did they charge for the cylinder if you do not mind me asking?
One of the next things I want to check out is the Treadle valve. I took the "foot Pedal" off and moved the valve piton cover around and had some little bubbles show but need to investigate how that is assembled to be able to replace "O" rings or? in it. Looks like it comes out the bottom way but will pull the gen set out again and look from underneath. Anyone taken one apart??
John H
Howdy John,
Cylinder was $270 after 10% discount. Pricey, for such a small diameter cylinder. Anyway, if you find a source, please post the link.
Good luck, Dave A
Wow, that is high! I looked at many last night on google and figured it should be under $100 but could not come up yet with exact stroke length etc (but close). I would say it is Chinese looking at quality!!!
Thanks
John
John H
I would ot replace my slide cylinder again, instead would install a air solenoid to block the PSI to the slide assy, wire it so it would work when you selected movement in/out, otherwise p;ass no air. Do not think with zero PSI the slide would drift in/out and secondly I never close it as I travel alone mostly. Also being cheap & tachy and love controls, would be simple. ;D
Howdy Dave M, I would/will do the same thing. Might even put a manual on/off valve.
Dave A
Dave A
The horn air solenoid is the perfect fit, Being an ASCO rep, I would use the ASCO Red Hat 12 VDC like I had all over my MCI coach, they work. They are very available thru WW Grainger too.
Now this sounds like the real fix-thanks
JohnH
Howdy Dave M,
Great idea!! I've added this project to ever growing to-do list!!
Dave A
Need to see how this idea works with the flip step foo, when your parked, step out no more need to keep air leaking thru all the pkumbing until you restart. Does it take air to keep the step out ? Do not think so. Know it requires air to close,
Just wondering, looks simple so far.
excellent idea using the added valve.No more leaky air at that one with this done, and that cylinder is a touch hard to get out. The step stays down does not need air.
Removed the park brake valve today and put new O ring in ,cleaned up and back together-simple as Wyatt said. I just have to see about getting the foot valve apart as that does need a re & re for sure. I think after these fix's my air should stay for days at full pressure (or close) and at moment my rear tank holds good but the front one is the one with all these things on that I am working on.
John H
What a great idea to remove constant air pressure on the slide piston. Both the step slide and our drop-down step are already controlled by 4-way pneumatic valves that bleed air from one cylinder end or the other end, depending on open or close position. But a new valve on the air line going to the 4-way, would have to be a 3-way valve, so when air pressure it turned off, it will bleed off the captive air. Otherwise the cylinder would still be pressurized. And we can't protect the drop-down step the same way, as it needs pressure to keep it in closed position.
The two 4-way valves have one shared input air line behind our step. We could put one 3-way valve on this shared air line, controlled with a single electric switch that is activated after settled in a parking spot with engine off and door open, so slide is open & step is down. But if we accidently drive off with the new switch activated, the step will not close, which will be a disaster.
I have never rebuilt the treadle valve as I wanted someone else to have the liability for the part. I have replaced quite a feew of the treadle valves and they are not very expensive for rebuilt valves
I think I would have each valve supply each side (direction) of the cylinder and replace the current control switch with a three position, spring return to center, switch. You would need to plug one port on the current valve and run one extra wire from the switch to the new valve.
As far as the exterior flip down step, it does stay up with no air pressure in a static condition but I wouldn't want to trust that it would stay that way while traveling down the road. Converting it would require some thinking on how to assure it's always up while driving but still always goes down when the door is opened...with out having to remember to flip a switch like you mentioned.
Barry, for the slide cover one why cannot you just put inline with feed air a NC valve and wired to the present one (for that specific slide) so that when you operate that switch it just opens up the supply line and then the presently installed one does the direction and exhausting for it. The 12v at the valve will allways allow you to open and close this new valve, so no change, except the air is now unable to leak constantly. Something like this one
1 4" SS 12V DC Solenoid Valve Stainless Viton S20V | eBay (http://www.ebay.com/itm/1-4-SS-12V-DC-Solenoid-Valve-STAINLESS-VITON-S20V-/290948688749)
The step is another issue I agree.
John H