Early 1970's Bauer Capitano Info

[pescador775]

When ordering connectors for oil gauge don't forget to also order an adapter to fit to the 1/4 inch pipe fitting on back of gauge.

Bauer seems confused about blow by.. I can't give you official numbers. Suggest you purchase a Brooks Instrument/rotameter, flow meter. Range, 0-1 cfm. These things are very expensive but sell on EBay for 20 bucks. If blow by at 3000 psi is not more than 0.5 cfm I would not replace any pistons or rings for now.

I assume your unit has the brass head on #3. Don't replace unless necessary.

 

[pescador775]

During repair and maintenance:

Collect parts to install a PCV tube. Remove 1st stg head or; Insert rag in intake pipe, drill and tap intake neck 1/8 inch NPT. Insert barb. Remove rag and metal chips. Remove plastic blowby vent and tap. Screw in barb. Run hose from vent to intake. No hose clamps, just use a flexible hose which will slip on to barbs.

 

[pescador775]

Test the 3rd stage piston:
Remove the piston and sleeve. Coat the piston with 30W mineral oil. Common "heavy" grade medicinal is OK. Place the piston into sleeve and note the time that it takes to fall through the sleeve and drop out. If it takes longer than 7 sec it is good to go.
Pesky

 

[Fastbird]

What is the best way to remove it? I looked at how easily the piston slides within the sleeve and it will slowly sink to the bottom. It has no roughness or stickiness. It glides smoothly.

 

[pescador775]

As mentioned earlier, the piston can be removed with a magnet. The sleeve is held loosely by a pair of O rings. I've removed sleeves with a magnet also but if this can't be done some other method is needed such as a rubber bung. IOW, insert something like a brass freeze plug or make something similar from tubing. If you feel the piston is fairly tight maybe removal is not necessary. However, "roughness" is not an indicator of a floating piston of this type. If there is a wear pattern it would only involve a slight difference in internal diameter of the sleeve top to bottom (the piston is harder than the sleeve and wears less). This pattern could be estimated by partially inserting the piston from the top and then trying the same from the bottom to observe any difference in slop. I see no reason to do this, just do the drop test if you need to know with some certainty the condition of the piston/sleeve. I would not bother with it until the compressor is running and a blowby test has been performed. If blowby at 3300 psi is .5 cfm or less and oil consumption is minimal the pistons should be OK for now.

 

[pescador775]

See below for pic of old Capitano which has a PCV tube installed.

 

[Fastbird]

Thanks for the picture. That really helps understand the concept a little better.

 

[Fastbird]

New question... about the PCV.

Why put air from the crank vent back into the air intake? The goal is pure air right? Wouldn't this potentially allow contaminates into the air and cylinders?

 

[windyairman]

First i have copys of all old bauer spare parts lists
but i have to photo copy and send by land post
this costs money
all other board members that i have sent copys to DONT EVEN PAY POST COST
so now its money first. To cover costs.

Right got that of my chest

If i can help i will

First re info given from 775
Do not remove piston from liner from the top
piston is allways removed & fitted into liner from bottom.

Another way to test for worn unit is with cylinder head removed
run up unit & look for oil by pass between piston & liner unit.

Blow by is 15 to 20 lt/min for your unit at 200bar

 

[pescador775]

Thanks Windyair, I must have been thinking of the Utilus 10. No problem removing from top or bottom. I haven't seen any damage to the bottom of the few pistons which I removed from top. They were very smooth and came right out. There are a lot of numbers around for blowby but none of them worth much. Bauer, Norfolk (Bauer USA) quoted to me from a Capitano book a number of 18-25 lpm which is unbelievable unless the compressor is a bit worn and pumping to very high pressure. More likely, they give that number to the public to reduce warrantee claims. I could agree with 20 lpm @ 4400 psi but not at "200 bar". I would have to investigate a reading like that. Others may disagree but I have checked a couple of pretty old Capitanos with low to moderate hours and measured 0.5 cfm (14 lpm) @ 3500 psi. I thought that was high until I talked to Bauer. However, if their number were correct the compressor output would be only about 4.5 cfm. The blowby level would not allow more. That would annoy me. I spoke to a German friend who built and overhauled compressors for 30 years. His reaction to the 18-25, quote---- "Was?, unglaublich"! IMO, anything more than 10% of rated output is worrying.

Fastbird, Bauer reroutes the blowby gas with all compressors since about 1977. Ask them.

I forgot to mention: If the magnet is strong it can be used to remove the piston/sleeve together, at the same time. That way, the piston can be removed from bottom. All this is academic until basic function tests are run including pressures of each cylinder......but I am repeating myself.