i.d Bauer compressor

[stingray22]

greetings divers, i have a vintage bauer with a plate on the block, it reads cable mako 2.5 cfm 32oo psi. mo. fa 13 e rpm 930 i have filled about 10 80s at 2500 psi. then the problem. the 2 nd stage is getting too hot to touch and the 3 rd stage is cool mabe too cool.the pressure is taking longer to build up. I removed 2 and 3 heads to examine the valves but without a manuel to refer too im just looking for the obvious.I Retorqued the heads to utilus specs. The problem is still there.This machine was on a n old sailboat and belt driven of the maine engine.I am using a 220 motor 2.5 h.p. I turns it at 950 comp. r.p.m. Is this a canidiate for the smithsonian or are there parts avaiable.In the filter is a stainless carthridge about 6 in. x 1 in. filled with charcoal. I renewed the charcoal and the air tastes smells ok and no evidence of oil on a white cloth.I know this is long winded for my 1st time on the forum but hey. any info greatly appreciated. James.

 

[Isaac-1]

Can you post a photo of this compressor, If I was guessing based on the CFM rating I would guess you have customized Varius block. Chances are reasonably good that parts are still available, I have a 3.2 CFM Bauer Purus (mine was built in 1978, but the Purus design dates back to the late 60's with some changes over the years) and almost all parts are still available. It could be something else though, as your RPM's seem low for a portable compressor (the Purus is rated from 1600-1800 rpm depending on if you go by the manual or the name plate), some of the older larger units would run at lower rpms. If you do get it running right , at a minimum you will want to upgrade the filttration on this unit.

 

[wwunder]

I have a bauer k-13, which is possibly the same... I think the vintage is early 70's. It is about a 2.5 to 3 CFM although I run mine a bit faster than 900 rpm. The 3rd stage pressure valve is hard to come by, but I got a replacement from jordair. If you aren't getting full pressure it could be a problem with the valves or the 3rd stage floating piston. Is there a lot of blowby coming out of the crank case? I replaced the 2nd and 3rd stage valves as well as the 3rd stage piston and sleeve. It still runs a bit hotter on the 2nd stage, but other than that no problems.

 

[oxyhacker]

Running just charcoal in that tiny filter is old fashioned and relatively ineffectual, current thinking is that a filter should hold mostly 13x molecular sieve. However that filter (I have the same one) is so small that there is some doubt you can fit everything that should go in it in adequate quantities. The little Coltri cartridge, which is about half again as big, is good for 1800 cf of air tops, and that's under idea conditions, so yours, if perfectly filled, might be good for half that. So you will probably want to add a more substantial stack; a good low cost alternative would be one of the converted hydraulic accumulators Shelden Sporting Goods sells.

Definately not a compressor for the junk pile though - Bauer makes good compressors, and parts are still available for just about all of them, so they are always worth rebuilding, and your sounds like it may just need a bit of valve work.

 

[pescador775]

Second stage intake pipe should be warm and discharge pipe should be hot. Due to age, replace valves on third stage. Describe type of valves and condition of valves on second stage. Fix mechanical problem before worrying about filtration mods which can be fixed at later date. Do what the label says and "cable MAKO". They won't bite you. At least, they may provide some info on this thing. Also, SB's Craig might know about it.

 

[CraigAClark]

I think Pesky is on the right track sounds like the final stage valves might be the culprit, but I would think the second stage safety would be lifting. Does your machine have either a round metal or plastic Fan cover and is the actual fan driven by a small belt? What you describe sounds like the older style Purus. If I recall correctly, the final inlet was a 007790 (they have changed the part number 081409 and the old valve tool won't work) price is $54.90 and the discharge valve was a 007780 which is still available and the price is $67.80. The discharge valve was unique in that it was a male allen with no tensioning stud, which threaded into the head and unfortunately the newer 014121 will not work.

Craig

 

[pescador775]

The old valve tool won't work on the new style intake? My old Capitano uses the 7790 valve. Fly in the ointment, maybe.

I wondered about the relief valve on the MAKO, too. It's possible that the intake is stuck open on that third stage but I would like to hear about the second stage. He might need to disconnect the discharge pipe from the first stage to see how much flow is being generated. No flow, no blow off of relief. Might be a stuck second stage intake but we need to hear what the valve looks like. Also, the blowby check is a good idea. Stingray didn't mention why the unit was only pumping the aluminum tanks to 2500 psi. Later, the volume dropped off but that seems kind of sudden making it sound more like a flow control problem traceable to valves as opposed to volume or pressure production problem involving pistons/rings. That sort of thing should not occur suddenly but slowly over time.

 

[CraigAClark]

Pesky, your right, but he did say he had filled a number of 80's to 2500 and that the problem then "occured". He really hasn't clarified if he is still able to get that pressure any more. I agree that "blow back" will decrease the out put scfm, but if those tubes are as described (heat wise), I have a feeling that either the final inlet is stuck open (as you mentioned) or both the inlet and discharge valves are the issue. Some times the valves can be separated (if you are careful), but if those small springs are shot, you're done.

BTW, if you need one of the new valve tools, drop me a line at craig@yachtdive.com and you'll have one on the way!

You know, I just remembered something that I have seen on rare occasions. Keeping in mind that the valves are basically check valves that require back pressure to seal (the springs aren't designed to seal the plates without assistance from pressure building down stream and basically only work when pressure on both sides of the valve plate is balanced). It is possible that the final stage valves are fine, but the floating piston is stuck at the top of the sleeve, and down stream pressure is that of the second stage. In this case the inlet and outlet valves of the third stage would be forced open by the second stage pressure and since there isn't any pressure build up from 3rd stage compression, the 2nd stage safety would not lift. What do you think Pesky?

Craig

 

[pescador775]

Don't know for sure. I suppose that the second stage would continue to work against the load downstream until the one of the relief valves blow. That might occur sooner or later depending on the design of the discharge valve, the spring tension, the size of the exhaust passage in the head and the tank pressure. I don't know the normal second stage IP for that pump but it should be 650-700 psi. I would guess that the #2 relief valve would blow at about =<1000 psi. I think Bauer uses fairly large drilled passages so that might mean that the tank could lift to about that pressure before something gives.

I'll contact you about the spanner, thanks.
Pesky

 

[stingray22]

hey, guys thanx for all the info. the floating piston was stuck at the top. i had to push it in with a rachet handle and rotate the flywheelmany times to free it up. not sure if it beeing forced back down by the 2nd stage air.the 3rd stage is cool both the cyl. and both lines.dont believe its operating.the final pressure i achieved was 1800 psi and the pressure build up took so long, 5 min. for 100 additional psi i shut her down.im goin back in for another look around. the one valve on the 2nd stage is held in by a allen bolt with a cap nut on top. the cowling for the fan ii metal not plastic.will send a pic of the machine tonight. thanx james