Bauer ACD auto-drain rebuild

[TravisD]

So, what's involved in rebuilding/maintaining these Bauer auto condensate drains? I don't (yet) have a problem per-se, but last time I ran it I did once catch it not closing after the timer should have - one stage (I forget which one) seemed to be hanging open slightly. A couple of taps with a screwdriver handle closed it and it seems to have been fine since.

My use of this unit is sporadic - looking at my logs I've put 30 hours on it in the past year. It's a 2001 ik12.14/BP13 package that I acquired from my LDS when they closed. It has 33xx hours on it. I do have the full manual but know those can be deceiving so before I start tearing into anything blindly, figured I'd ask.

Is this a "if you open it you MUST replace parts" situation, or can I disassemble, clean, reassemble, perhaps with some o-rings. Yes, the vinyl tubing is ancient and crusty - I have replacement to go in at some point but since it's just drain lines I haven't been in a hurry

 

[happy-diver]

Yeah some orings

https://scubaengineer.com/pictures/compressors/bauer/ik100_120_ii_english.pdf

And resist unscrewing any of the steel fittings from the aluminium

 

[TravisD]

Good point about the dissimilar metals - I'll have to look and see what my options are there.

I'm seeing the rebuilt kits for like $130US and would prefer not to have to throw a bunch of parts at something if it's not really needed...

 

[oldairdude]

Travis,
There is nothing that MUST be replaced, if you open and inspect, lube, etc. in fact, it’s an annual suggestion in your manual. I have repair kits that can replace all wearing parts that are inside of the three units. I can also provide, if you need it, the breakdown of your specific build. Here are some Pro Tips from my experiences:
1. Note that the two ACD units on your right are numbered 64008 and 64009 on the body. The 64008 is your final (right side) unit. The 64009 is your 3rd stage drain mounted in the middle. while they both use the same wearing parts, the blocks differ somewhat in that the final unit has a spring on top of piston and utilizes a restricted orifice fitting on the bottom. Do not swap these units positions.
2. I suggest you remove the block from the manifold, with the two Allen bolts in the middle, then work on the block with a table vise. Remove only the top and bottom caps from the middle. Do not yet, remove the steel tube compression fittings from the aluminum bodies, as these are sometimes drama with dissimilar metals. 50/50. If done annually, fine. However if its been years, it may not be worth it unless you have to change it for some reason. If you ever do, always use Anti-Seize afterward and avoid future drama.
3. Make sure the restricted fitting is clear, you do not need to remove it. It is a very small hole and can often plug up. If you can pass some air thru it, you are fine.
4. The most wearing item are the Delrin seats. They are the same in both blocks. Unless someone beat you to it, they are also reversable with a new surface seal on the other side. Hence why a suggest once a year so you can use both sides before ever replacing. If tip of piston is chipped or eroded, you will need to replace it. If it is not leaking now, the pistons are most likely in good shape, however, they should be re-lubed with silicone grease in the bores and U-cup seal.
5. The spring on top of the piston on 64008, is usually a mess with corrosion of the aluminum block it sits in. Clean it up and as long as the corrosion has not reached the groove of the O-ring, you should be good. Again, why you should do it annually.
6. The solenoid valve is the 2nd stage drain, electrically driven. Check to see that it drains as soon as unit shuts down. Re-lubing helps here as well.
Have fun and if you need better details or drawings, let me know!

 

[TravisD]

Thanks Porter! That's the kind of insight I was hoping to come away with. I kind of doubt that these were regularly serviced, so hoping it's not too late. Once I"m sure I'm not going to be pumping for a little while I'll pull them out and get to disassembling.

 

[TravisD]

I *think* I've got it back working correctly again. For those keeping score at home - the Final (008) valve didn't look at back. Little bit of buildup inside, but for the most part decent.

the 009 3rd stage valve had a bunch of brown goo in it, and gave me a little more trouble. It cleaned up decently, but the seals and o-rings have swelled a little, so took some coaxing to get them back seated correctly. I believe I have the O-ring sizes in my manuals so I'm going to order up a few of each to have on-hand. The seats looked great.

I put it back together and did as text run, and... testing by pulling power to the electric solenoid resulted in it hanging open again.

So, I pulled apart the electric valve and cleaned some crud out of it, lubed and reassembled. After a couple of manual cycles it seems to be behaving now. I'm letting it continue to run to finish topping my my banks, hopefully without any more sticking.

O-rings and perhaps a rebuild kit to have on hand just in case are on the shopping list now. Thanks all for the great advice!

 

[oldairdude]

Travis, glad to hear you opened it up and checked everything out. If you do this about once a year you will find that it will cleanup quicker and seals will last longer with a little lube done annually. The solenoid valve is the thing that causes the delay in dumping. There should be no delay when you unplug it or at shutdown. It shows up more at higher final pressures. I know the reason for it happening, suffice to say that the next time you open the solenoid valve up again, you can firmly stretch the smaller inner spring that is attached to the piston. NOT the larger outer one. The inner spring is what breaks open the vent when power shuts down. Give it a bit more strength by stretching. It’s a field fix, perhaps temporary…
Good luck!

 

[TravisD]

Yeah, especially since I now know my much those parts cost to replace, they will begin getting regular attention!

As far as delay goes - the solenoid would open and start dumping condensate right away. The problem was failure to *stop* dumping after the 10-second timer expired. In testing I let it go for 30+ seconds and was still seeing venting coming out of the silencer into my catch reservoir, at which point I shut it down and started tearing things apart. This would have been at around 3000psi leaving the PMV (I top my banks to 4500 since most of what I fill are HP's). The little plastic seat in the solenoid took some convincing to come out initially.