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tim24der
03-09-2011, 04:29 PM
Tom,

I hooked up the 4500 SB yesterday to refill my tanks.
This was only the 3rd time I had used the Shoebox.
On previous usage I was sure to stop every 2 hours and regrease the piston shaft with the white lithium grease.

When I started everything up today the shoebox shut off almost immediately after start up.
I tried the soapy water trick and found that the bottom cylinder was leaking badly.
I followed your video and was able to replace the washers.
The bottom washer was not found so I took off the back check valve end and found the washer there.

Is it commom for this to happen ?
The washer didn't look deformed or damaged, but I went ahead and replaced both white washers and the black one on the back check valve as well.

While checking for leaks on the cylinders I noticed that I have a bad air leak where the quick coupler screws into the block.

I tried re-wrapping it with the sealing tape several different times and nothing worked.

Cylinder was repaired and everything started back up fine and I managed to get my 88cu tank filled back up to 4500, but I still have a serious leak around the quick coupler and in rechecking the bottom cylinder I noticed there is still a small leak there as well.

Any ideas or is this common to have leaks like this at the quick coupler and cylinders ?

Thanks !

TomKaye
03-09-2011, 11:42 PM
It happens that the lower cylinder eats the oring and it ends up in the back check. Glad you got it fixed. Something is strange with the leak in the output fitting. Did you use teflon tape or paste?

Tom

tim24der
03-10-2011, 12:25 PM
Tom,

I used teflon tape.
I tried a few wraps - still leaking
I took it off and tried many wraps - still leaking.

Tightened it down as far as I thought possible without stripping the threads - Do you have a torque setting for the coupler ?

The cylinder repair was fairly simple, thanks to your excellent video.
Should the cylinder still be leaking air after replacing all the o-rings ?

Thanks,
RB

ShoeBox Tech
03-10-2011, 02:23 PM
Tom,


While checking for leaks on the cylinders I noticed that I have a bad air leak where the quick coupler screws into the block.

Any ideas or is this common to have leaks like this at the quick coupler and cylinders ?

Thanks !

What serial number do you have?

Which quick coupler do you mean? The one on top [input] for the feed or the bottom front [output] to tank?

Is the leak from around the piston or around the cylinder?

If its around the cylinder you will need to replace the black orings on the outside of the cylinder. If its at the piston, its the inside orings. Check the inside orings for fit on the piston when you remove them. Clean off the end of the piston and the rings should fit SNUG not loose. Its possible you got a bad new oring. Also when you replace the hollow set screw it should be just a hair past finger tight.

tim24der
03-10-2011, 04:10 PM
The only numbers I could find were etched in the block above the upper cylinder.
It says 212 4500.
The coupler that is leaking is the top input. And it is quite a large leak. Many bubbles upon application of soapy water !

The other leak is around where the piston enters the cylinder.
It was a large leak there before I replaced the o-rings yesterday.
After o-ring replacement the leak was much smaller, but still there.

The set screw was set per Tom's instructions in the video.

tim24der
03-11-2011, 01:44 PM
Tom,

Please give me a call today if you get time.
After our call yesterday, I double checked everything you'd mentioned.

Still have the leak at the quick coupler on the top of the SB and now it's acting up again.

I was going to top off the tanks and check for leaks again.

The SB filled from 3900 to 4150, it continued running, just would not put any more pressure in the tank.

I tried it on several tanks and the same thing. SB runs but will not put any air in my tanks.

I unhooked a tank to see if anything was coming out of the bottom valve on the SH and it was fine. Plenty of air.

I took both cylinders apart again and re-checked them and everything looked fine there.

Fresh out of ideas now

Thanks
RB

TomKaye
03-11-2011, 02:21 PM
Is this Rick? I make several calls a day and its hard to connect the forum nicknames to real people. If not email me your phone number.

Tom

tim24der
03-11-2011, 04:10 PM
Tom - yeah this is Rick 919 524 2969

bdurham
03-11-2011, 04:32 PM
My valve on top wanted to leak. I had to put a lot of tape on it but it sealed. I think the valve is made a little large.

TomKaye
03-11-2011, 08:58 PM
We are checking into it and it looks like the fitting threads are out of spec. This is a McMaster part too....

Tom

tim24der
03-11-2011, 11:08 PM
Good News - Bad News Tom

I was able to fix the leak on the upper coupler by adding more teflon tape like bdurham suggested.

But now

http://i828.photobucket.com/albums/zz204/rbolton6/all%20pics/DSCN1242.jpg

Major leak at the bottom of the block now. I have never seen this area leak before and I have been spraying a LOT
of soapy water on everything the last few days.

I did empty the little tank like we'd discussed and starting re-filling it, but it was going so slowly I knew something still had to be wrong.

The soapy water revealed a new BIG leak at the bottom of the block and the same small leak on the bottom cylinder on the piston end

RB

tim24der
03-14-2011, 11:35 AM
Tom,

I took both cylinders out this weekend and cleaned everything up.
Put it all back together and MAGIC - It is back working again.
No leaks anywhere this time !

Seems like just a matter of tweaking everything down just right and not too tight on the cylinder piston end allen screws did the trick.
No more leak on the top end quick coupler as well.

Thanks,
Rick

TomKaye
03-14-2011, 03:25 PM
If the leak out the bottom of the block stopped it could come back again. If it does do not take the unit apart until you contact me.

Tom

tim24der
03-14-2011, 04:51 PM
Will do Tom !

Thanks,
Rick