ASK - Bauer with pressurized oil lubrication compared to Coltri splash lubrication

[veriqster]

in the ringless design the fit of the piston is very tight so the oil pressure is needed to both penetrate / lubricate and prevent blowby, once that is taken out of equation by using rings there's no need for such oil pressure, the rings take care of both space for lubrication and sealing of the jug.

on the other hand i tend to disagree regarding "testing conditions" for different brands of compressors. the data is there, at least in US, plenty of public institutions have them, operate them and contract service for them (firefighters, military, research facilities and not only). it's just that vendors / manufacturers choose to not make the data public. call me paranoid, but if i am right, that data would pretty much destroy any advertising claims they make. i think the best way to judge the quality of a unit is by reding the fine print in the warranty it comes with. that and the price tag, finaly you get what you pay for.

 

[shil]

If I remember right the Coltri s are 4 stage compressors, and the last final stage is at the bottom. Yes, bottom of the oil sump, so the 4th is sort of immersed fully in oil. Which eliminates additional oil pumps, drawback is any dirt will go down , to seize the 4 th. so it' s very Important to pour in oil very carefully, and also to change oil at factory recommended hours without fail, otherwise ...thud.

Shil

by the way this is a great thread started by Iya

 

[oxyhacker]

The little Coltri is, and does., and the precautions you mention well worth taking. The larger Coltris are, though, either along the lines of Bauer Capitano/Mariner, with three cylinders on the top, or 4 cylinders in an X with a sump well below.

If I remember right the Coltri s are 4 stage compressors, and the last final stage is at the bottom.

 

[IyaDiver]

Hi Shil,

Only big one MCH30 and MCH36 I saw in the part list its a 4 stage with 4 pistons and I read it has an oil pump and oil filter and "X" ( its that what its called? ) configuration of the pistons directions of travel.

MCH13 to MCH 18 is 3 stage only.

Funny thing the Mariner 320 part list call its last piston ( floating one ) as 4th stage. Maybe its the language translation from German to English. Isn't a definition of a 4 stage means it must have 4 real pistons connected to crankshaft ?

IYA

 

[oxyhacker]

Some of the Bauers will fool you, they look like the 3 stage Mariner/Capitano line, but have an extra cylinder stacked on top of one of the others. The seem to have goin to this construction on most of the intermediate-sized compressors.

Though I notice the 320 is listed as being 3/4 stage whatever that could mean!

Funny thing the Mariner 320 part list call its last piston ( floating one ) as 4th stage. Maybe its the language translation from German to English. Isn't a definition of a 4 stage means it must have 4 real pistons connected to crankshaft ?

IYA

 

[IyaDiver]

I see Vance, that is interesting....thanks

 

[shil]

HI Iya,

mch-6, is 4 pistons for sure, opened up one 2 years ago, to replace the seized 4 th. Owner dallied changing oil. and it seized. Change oil in time and they run fine, overhauling is a breeze as it is quite simple and parts available from any where any dealer, (unlike some other big brand) and economical to boot.

Shil

Shil

 

[IyaDiver]

I just got my new Bauer 200E.

The book said oil pressure is 5 BAR ( 75 psi ). not 10 BAR.
There is no oil line to piston no 2 liner like the old 50 BAR Mariner, so its probably splash lubrication for piston 2. Part list does no show how the piston #2 look like from top view, its drawing of a side view. I would like to know if it has holes in the piston like piston #3.

The oil capacity is now 2.8 liters compared to 1.6 liters of old block. I like more oil capacity, its a good sign of more heavy duty design.

The shape of the cylinder heads are a bit different now.
The first stage reed valve is a bit different than my old one, if I see the manual.

The final aftercooler pipe looks like it has stainless steel fins now, the old one year 2000, only the pipe is stainless but the cooling fins is steel, may be press fit. If this new one is welded, I hope for better heat transfer.

The two coiled intercooler pipes of stage 1 & 2 still look like aluminum, can't tell untill I scratch the finish or dismantle it. I thought it should be stainless steel by now. If its stainless, they would not paint it silver color.

The carry frame is aluminum with sort of orange skin finish, rough finish. Weights a bomb with a P41 filter system.

I will remove the complete belt guard if I operate it, I feel the air flow will be slowed down by it.
The old mariner fan push air a bit on "outward", let see how this new one perform.

The pulley/fan is different now, it has more skew on the blades. I think it should deliver more air than the old one...I hope.

That's all the report for now.

IYA

 

[IyaDiver]

You are right Shil.
I just downloaded the schematic, I never pay attention to those above 2,000 RPM unit be it Bauer of Coltri, the run too fast for me.

You are so right, it makes real sense, the dirt will be fed to the 4th piston if oil change schedule is bad. So Coltri does not use floating piston for MCH6....nice info !! Thanks.

Can one use a magnetic ( super magnet one ) oil plug, to at least catch ferrous dirt which can stick to magnet ?

IYA

 

[rcontrera]

Sure ... you can stick a magnet on the drain plug but the real damage comes from water. Just like a car engine, you need to get the temperature of the oil up so that any water accumulation will evaporate. Since these are mostly used by individuals that only fill one tank, they rarely get hot enough to cook off the water in the oil. Then, if that water/oil emulsion doesn't get changed before putting away the compressor for the season, it just sits on that forth stage and causes rusting. I just talked with a guy that had very few hours on his but had it sitting out in the garage for a few months and the forth stage piston was pitted bad. That's why I tell my customers to change oil at 25 hours and before putting it to bed for a month or more.