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crboy
04-13-2011, 03:44 AM
Well I had it up and running but heard it shut off earlier than normal. Went to take a look and the pistons were seized in the cylinders. Took the top cylinder off with great effort. Seems like the same as my first problem with the airblock. Once I got the top cylinder off, I could see scratches on the outer part of the cylinder where it goes through the airblock. I can't see any debris and I use a dirt/water filter just before the top input.
I took the o-rings and spacers out and test fit them to the piston and noticed that the larger spacer (part #7) was so tight that when trying to put it on the shaft, the shaft assembly moved away from the spacer as if the spacer id was too small. Upon closer examination I noticed the piston wasn't as smooth as before. It almost feels like it is flat sided. I blow out the parts before reinstalling so I can't see dirt or anything getting in so I am guessing the filter is letting dirt or something through.

I took off the lower cylinder off with no problems so it seems fine. I've reinstalled everything and fired it back up but now the recharge rate is dead slow. With the end of the gauged line blocked, I turned on the shoebox and instead of seeing the needle climb like in your test video it moves so slowly....3 minutes later and it reads just over a thousand psi. Your thoughts and has this happened with anyone else's?

The shrinking ID of the spacer has me scratching my head...

ShoeBoxAdmin
04-13-2011, 08:49 AM
What serial number is it and did you ever unbolt the main aluminum air block?

Tom

rsterne
04-13-2011, 03:33 PM
The shrinking ID of the spacer has me scratching my head...
Is there any possibility that humidity and pressure are causing the plastic to absorb water and swell?.... Just a thought, as some plastics are susceptable to things like that.... Maybe that is why some people are having more problems than others.... different humidity levels?....

Bob

TomKaye
04-13-2011, 11:31 PM
No its heat expansion. We redesigned the later spacers to accommodate that. That's why I want to know the #

Tom

crboy
04-14-2011, 02:09 AM
I had #115 but you replaced the block when that one had the same similar situation. In that one I couldn't get the cylinder out of the block.

TomKaye
04-14-2011, 03:22 AM
Did we get the whole thing back for replacement or did you bolt in the block?

Tom

crboy
04-14-2011, 04:53 AM
I bolted in replacement block and piston assembly, ran fine for 70+ hrs with a couple o-ring changes in that time allotment.

ShoeBox Tech
04-14-2011, 06:05 AM
I bolted in replacement block and piston assembly, ran fine for 70+ hrs with a couple o-ring changes in that time allotment.

Right. I built you a new block and piston assembly. Double checked all the fits and Bench tested the assembly for function.
It passed all testing and was sent out. I think I sent a note saying you would have to align the block to the support bracket.
Are you sure it was aligned to the support bracket?

If the shaft is flat sided it most likely wasnt aligned good and the cylinder is probably damaged and it is most likely leaking past the cylinder rings, hence the slow fill.

Guys, you have to be careful when removing the c-clip[snap ring] from the cylinder. If you scratch the cylinder when removing it the cylinder will get stuck in the block when trying to remove it. You really need GOOD snap ring pliers.

Also your rings should last more then 70hrs. Be sure they are leaking before you replace them. Keeping the input air clean is more important then dry. We test to the extream and moisture for the Box isnt a issue. We test with out a moisture trap of any kind. I could say more but the boss would keel me. :{

TomKaye
04-14-2011, 06:14 AM
Take off the motor and send us back the whole assembly. We will rebuild it and send it back to you. Don't take anything apart, we want to see what happened.

Tom

crboy
04-14-2011, 11:04 PM
Ok, I will ship it out friday. Did you move yet or do I ship it back to wheeling Il.

TomKaye
04-15-2011, 04:58 AM
Send back to wheeling.
Thanks

Tom

crboy
05-10-2011, 03:42 AM
Got shoebox back today and it's up and running like new. Thanks Tom for the service above and beyond mere mortal companies.