Davey MC1A

[Graeme Tolton]

Greetings All! I have recently acquired a Davey MC1A Compressor. Unit has 311 Hrs on it and aside from gummed up fuel system, seems to be in great condition. I know that there are a lot of these units out there so I figured I would come here to ask some questions..
Of those of you who have been running these units, what lube have you been using in the hatz diesel engine and the pump?

It will be running in varying temperatures, from -10C to +35C.

The original compressor inlet filter system is gone and has been replaced by a long hose with a filter stuck on the end of it. I do plan on building a rigid stack for it out of pcv pipe, but also would like to in time add a stick for blending nitrox and trimix. Does anyone have a similar setup with pics? Just looking for inspiration.

As far as the filter stacks go, I plan to buy the original metal cartridges and once they are expended, repack them. Has anyone been replacing the mechanical filter (in between the two stacks)? I have been unable to open the housing. I had a strap wrench on the housing and a long bar on the studs on top and couldn't crack it free.

The 4400 psi receiver tank looks to be in great shape inside and will be going for hydro shortly.

As far as the fuel system, the previous owner had been using bio-diesel and the unit sat for a few years with it in the system. during this time, the fuel went bad and made a big mess of everything. The injectors and injection pump are being rebuilt, all the lines are being replaced and a full cleaning of all rigid pipe will be done. I am still undecided what to do with the tank, as it is full of gunk. I will either not use it at all or I will remove it, cut it open, clean it and re-weld it back together. Has anyone removed one of these tanks?

I will be running a CO monitor off of the former dew point indicator system.

Any insight into this machine would be helpful!
Graeme

 

[Graeme Tolton]

Ok, i have a status update! After countless hours and a fair bit of $$, my davey is roaring. I installed a brand new bosch injection pump, 2 rebuilt injectors, new fuel lines, filter. Cut tank in half cleaned out with a grinder and welded back together.

Engine runs amazing! Primed oil pump on compressor end and it pumps like a dream. Takes a minute or so to pump receiver tank to 4000 psi.
I am now just waiting on my new filter cartridges and synthetic oil to arrive. In the mean time i will be fixing a couple minor air leaks and hopking up my co alarm.

 

[Zodiacdiverdave]

Hey Cangrats on getting your compressor running I hope it works out for you. What filters are you using? Can you post a pic or 2. If you find your self driving to NS anytime soon I have a Davey block you can pick up for $150. It would give you some spare parts for down the road. As far as using the Analox CO monitor with out a relay installed I don't think it can be done. It might be better to periodically sample the air with the monitor. If you want to operate the compressor with a CO Monitor then you should order a new one with the relay installed.
If you are not running a dive shop or commercial operation then you may find that monitor very expensive to operate. It requires regular calibration and the cells require regular replacement and they are not cheap. In saying that they are a good piece of mind.
Looking forward to seeing the pix.
ZDD

 

[Graeme Tolton]

I have ordered the original metal filter canisters from august industries. In the one pic u can see where i have welded the fuel tank back together after cutting it in half to thoroughly clean it. It had been full of decomposing bio diesel. I ended up having to replace fuel injection pump and injectors, fuel lines.

What does the hi low regulator low range gauge indicate? I am lost on that! I may end up using the co monitor to check each tank. Not sure yet.

 

[Zodiacdiverdave]

I am no expert on Davey units, all I have is this old block but there was someone on an earlier thread that new allot about them. I will see if I can locate the thread for you.
The filters that came with this type of compressor were for drying the air only and just used Silica gel crystals. These units were used for airfield servicing and not BA compressors. You should really consider an up grade in the purification department.
The High/low regulator probably is referring to the output pressure regulators. Like I said earlier these were used on the airfield, starting systems, struts and hyd. accumulators were high pressure and tires were low pressure. The aircraft industry and military now use only nitrogen in their systems and tires.
One more upgrade I would consider if this unit was mine is to add an intake snorkel. You want to put as much distance as you can between the intake and engine exhaust but I am sure you already know this.
ZDD

 

[Graeme Tolton]

There are two different canisters. One is a dehydrator, the other is AC. I have been told that they can be cut open once used and repacked. The stack size seems to be sufficient. There is a dew point indicator as well that i will use.
If my travels do take me to the east cost, i will certainly take you up on that block, but it is unlikely in the near future.

 

[Zodiacdiverdave]

go to page 12 on this compressor forum, there is a good thread on your machine. There is also a phone number on one post for ProTec Air who can sell you a manual and parts for the compressor.
Frogman62 has some knowledge so you may want to PM him for good advise. Good luck
ZDD

 

[frogman62]

The High Low pressure gauge has a pressure limiter on the back of the gauge to prevent blowing up the gauge. The larger gauge just give you a better view of the low pressure reading instead of looking at a 5000PSI gauge and trying to judge the pressure in very small increments on the lower range of the gauge -- which is inherently inaccurate until you reach 1500 to 5000PSI
Jim Shelden
frogman62
<sheldensportinggoods.com>

 

[Graeme Tolton]

Ahhh! Makes complete sense now. Everything is progressing nicely. I will have my new filters tomorrow. The last step then will be air testing.

 

[frogman62]

I suggest you test the air with the old filters in place --before you put in the new filters. Testing after you put in the new filters tells you what you already know -- the air will be good. I prefer to test before changing the filter to confirm the air I am using last is still safe and it could show I am changing more often than needed. Since you have a "new to you unit" some intermediate testing will confirm what should be done -- change more OR less often.
Jim Shelden