Piston Replacement Appion G5 Twin

[PenZenMaster]

Anyone ever replaced a piston in an Appion G5 Twin? I've rebuilt the top end in three of them with no trouble but I can't find any information online on the piston replafement.

I ordered a replace piston from New Century Tools so I just need some advice on what to do.

 

[PenZenMaster]

The damage

 

[PenZenMaster]

The damage

The damage

[/IMG]

 

[gladstoned]

I have a brand new appion sitting here from Amazon and I cringe at the thought of this fucker constantly needing rebuilds. How bad are these things?

 

[JColtrane]

Well, I hate to burst your bubble bro ... but I'm almost 99% sure the kit you bought from Century Tool is just the piston "seal" kit. Appion doesn't sell just pistons or anything else really. After they got wind of what we were doing with them, they pulled the plug on all that shit. Lucky for us, the Chinese are smart, and the Pro Max RG 6000 is almost the same thing

You can order the "Major Rebuild Compressor Kit" from century tool that cost about $250. Your piston is fucked, and this kit is the whole thing. A few bolts, shouldn't be that hard.

If you're just using a recovery pump, I'd recommend replacing them every 50 hrs of use ... less break down. The only thing that's real tricky is getting the case back together. You might want to build your own, before throwing the thing off a bridge in frustration

 

[PenZenMaster]

I love my Appions. I own four. I rebuild mine when it takes more than 60 seconds to shut down on over pressure. I normally get about 2000 hours on a rebuild.

 

[PenZenMaster]

I purchased a dual top end kit and I also purchased a piston and shim kit.

I rebuild my own pumps so I have all the proper tools just looking for any advice I can get before I split the crankcase.

 

[skootdogg]

piston replace on Appion G5

piston replace on Appion G5

I recently rebuilt my G% with a Kit from Air Clean in Florida. The dude was awesome and gave really good advice and sells a seal kit that is really nice. The pistons and seals where really easy to replace and if you do 1 side at a time the thing is easy to put back together There is also a really good instuction sheet at www.hbbpro.com on doing a rebuild on the Appion G5. Hope this helps.

 

[Permacultuure]

I love my Appions. I own four. I rebuild mine when it takes more than 60 seconds to shut down on over pressure. I normally get about 2000 hours on a rebuild.

Damn! 2000 hrs? Can I fly you out for some rebuilds what do you think caused the piston to fail like that, looks gnarly

 

[PenZenMaster]

what do you think caused the piston to fail like that, looks gnarly

One of the reasons my pumps last so long is that I try to not let them pull against more that -20 inches of hg.

I ran this one to 100 microns and she sat there for a bit.

You should NEVER let a G5 run down to a hard vacuum and if you have to don't leave it running any longer that required.

You vacuum pump should do the hard pulling.

 

[PenZenMaster]

For the love of small furry things

For the love of small furry things

So I'm up against a hard spot now. I have to admit that these Appion pumps are built with the rebuild tech in mind.

Piston was piece of cake to remove. There is a 8m x 1.0 x 15 set screw in the crank end and the piston screws on to that.

Screw the old one off and put the new one back on.

Except in my case the set screw was stuck in the bottom of the piston.

I buggered it up trying to get it out of the old piston.

Now I need help. I'm pretty good with Google, but I cannot find a source for 8m x 1.0 x 15 set screws.

I can find 8m x 1.25 x any size you want, anywhere.

Like at Tacoma Screw

I'm half way between Seattle and Portland so if yo have a source anywhere in between I'd love to know about it.

 

[Rickys bong]

PZM, real easy fix for that bro.

Get two M8 nuts and thread them onto the set screw on the old piston. Thread the second one a bit past the end of the thread so it's roughly flush with the end of the screw, or a bit further.

Tighten the two nuts together, or against each other. Real tight.

Since the old piston is, well, slightly fucked you can grab it with a pair of vise grips and put a wrench on the nut closest to the piston.

Before you go further, get a heat gun and heat the crap out of the old piston to about 400f. That will release the Loctite holding the little bastard in.

With the nuts locked against each other it should screw out easily. When putting the new one on use some blue loctite to keep it from backing off.
Be very careful with the piston when tightening it up. I'd make two wood v-blocks to clamp it and then put a few layers of cardboard on the wood to keep from scratching the piston. Clamp the V-blocks in a vise.

RB

 

[JColtrane]

RB for the WIN!!!

 

[PenZenMaster]

Source for Screw

Source for Screw

Seems all it took was a request for help and prestro!

Source for 8M x 1.0 x 16 set screw

Appreciate the tip on removing the set screw from the piston, but I had already buggered the threads on it.

 

[Rickys bong]

Ooo. I thought you'd just buggered the Allen socket bit. Odd failure mode on the orig piston. Looks like the upper part cracked and a chunk broke off.

RB