Bauer Compressor 2nd Stage

[UnderwaterOrkinMan]

I do not see an id plate anywhere. Here is the pic

 

[Miyaru]

This is the gauge that drops from 800psi to 400psi in 15 minutes?

It's the oil pressure gauge. There should be a pressure switch connected to it, that will stop the engine when the pressure drops below 50bar.

This is the document that I think belongs to your compressor:
https://www.bauer-kompressoren.de/f...spare-part-list/mariner/1999-01-01_tm-3_8.pdf
Look at figure TM-7. Your compressor has an oil pressure gauge instead of an oil pressure switch. Partno. 33 in the drawing is for setting the oil pressure (and adjusting requires partno. 34 to be temporary removed).

If you're not sure about it, have it done by a technician. Running this compressor with an oil pressure of only 400psi is gonna wear down the piston on the final stage faster than it's supposed to. If you want to do it yourself (and have the metric-sized tools to do so!), I'll post the technical details.

 

[UnderwaterOrkinMan]

View attachment 605974
This is the gauge that drops from 800psi to 400psi in 15 minutes?

It's the oil pressure gauge. There should be a pressure switch connected to it, that will stop the engine when the pressure drops below 50bar.

This is the document that I think belongs to your compressor:
https://www.bauer-kompressoren.de/f...spare-part-list/mariner/1999-01-01_tm-3_8.pdf
Look at figure TM-7. Your compressor has an oil pressure gauge instead of an oil pressure switch. Partno. 33 in the drawing is for setting the oil pressure (and adjusting requires partno. 34 to be temporary removed).

If you're not sure about it, have it done by a technician. Running this compressor with an oil pressure of only 400psi is gonna wear down the piston on the final stage faster than it's supposed to. If you want to do it yourself (and have the metric-sized tools to do so!), I'll post the technical details.

Ok. I have learned that it was the oil pressure gauge. The theory was a bad/failing oil pump. I just replaced the oil pump. What procedure do you use to prime it?

 

[NAM001]

I will post the information shortly. I was told it was a Mariner 1st gen but Bauer folk seem to think it’s a capitano. I lean toward trusting the seller(as weird as that sounds).

It does not look like my capitano

 

[Miyaru]

Ok. I have learned that it was the oil pressure gauge. The theory was a bad/failing oil pump. I just replaced the oil pump. What procedure do you use to prime it?

After replacing the oil pump, I assume you checked the oil level. The oil circuit to the last stage should be bubble-free after a few rotations. If any air remains in the highest point (near the gauge), loosen the gauge nut until some oil seeps out, and close it. Tighten it when the compressor is not running (no oil pressure).
I can't see the oil circuit in the picture, there should be a glass section in between where you can check for bubbles. Older compressors used to have a transparent tube in the oil-return-circuit to check for bubbles.

With the compressor running, unscrew the hexnut covering the adjustment screw.

Set the oil pressure to 50bar / 725psi (clockwise to increase). The needle might be vibrating between 45 and 55bar, nothing to worry about.
If the pressure starts to drop after 10 minutes, check if you see any bubbles (=problem). Check the oil level again right after running when the compressor and oil are still hot, and the oil is still dripping back from the cilinders. It should be well above the minimum level.
A faulty oil pump can be a reason for the oil pressure dropping, or a leak in the oil circuit. Hot oil seeps out easier than cold oil (clean everything and check if it stays clean).

 

[Air Guzzler]

If your problem persists after replacing the oil pump, its probably the oil pressure regulator, which can be easily rebuilt. Spec plate for that unit may very well be on a sticker inside the white control box on the door.

 

[UnderwaterOrkinMan]

Ok so thank you all for your help. This was the final verdict. Changed the oil pump. Went from dropping oil pressure to no oil pressure. Went through bleeding/priming. No change. Loosened fittings and found that I had oil flow all the way to the gauge. Removed the gauge. Inlet hole looked askew. Replaced with new gauge. Tried again. No pressure. Went through bleeding/priming again. No pressure. Removed the oil pump that I had put on and replaced with the original because I knew that it would at least build pressure. Hooked everything up and turned on compressor. Pressure immediately.(400psi) adjusted the regulator screw and tuned it to 750psi. Only had time to pump one HP100. During that time the compressor ran normal and oil pressure didn’t drop. Time will tell tomorrow. I’ll have to start on my back log so I have gas for the weekend.

Side note: if you have to for whatever reason (in my case broke elbow and local hardware store didn’t have replacement) have to replace the elbow fitting and hose for the ACD. Do NOT go smaller than 1/2” ID. It creates back pressure and causes the pistons to cycle continuously.