daveys

[cowboy]

I bought 120 daveys today 15 cfm and a few big clarks 150 cfm to day will be shiping them home this week to tennessee. we will be building them and have them for sale in a few months. got jb hunt coming to haul them for me all together 3 or 4 tractor trailer loads also got some big tubes6000 psi will haul them myself

[trdscfjc]

Re: daveys

What model Davey is the 15 cfm machine?

[hypermilinggx]

Re: daveys

Davey model MC-1A is 15 cfm.

[cowboy]

Re: daveys

yep that is right I also have got some long airdoc compressors 150 cfm with 120 psi inlet 100 horse elt motors or I build them with small block chevys set up for natural gas

[Lakewood90712]

Re: daveys

yep that is right I also have got some long airdoc compressors 150 cfm with 120 psi inlet 100 horse elt motors or I build them with small block chevys set up for natural gas

Cowboy, what do you use for a drive coupling ?

[cowboy]

Re: daveys

belt drive as the airdocs are a slow turning compressor and gear boxes cost a lot and when they they go down take time and money to fix and when belts go down just call gates and you are up and running in very little time at very little cost .

[karl]

Re: daveys

Cowboy,
Have you experimented with running a davey at reduced speed/output?
If so how did it go? I assume there is a certain rpm/output range where it functions the most efficiently?
It seems like it could potentially run cooler, be quieter and enable compliance with the 5cfm max output requirement for residential compressors.
Thanks,
Karl

[hypermilinggx]

Re: daveys

Probably be difficult to make a Davey do less than 4 gge's.

[cowboy]

Re: daveys

I have been so covered up that I have not got to this project. I do know that they will run at 1000 rpm but pass a little more oil as I have had to run them slower because of limited gas supply I just ran the diesel motor slower. this is project 1487B LOL just not time to do them all. 4 gge was about what I was doing don't know how slow I can go as that was how much gas I had

[karl]

Re: daveys

Cowboy,
I end up with three specific questions: oil pressure, replacement parts and oil type

The issue I would worry the most about is the compressor oil pressure. Have you found any ways to boost the oil pressure? Different regulator spring, heavier viscosity oil, ...

Is there still a supply of Davey parts available? Bargain Marge doesn't seem to have much on her ebay site. Once upon a time she had her entire Davey inventory up for sale. Did you buy her out?

Flattrackers explanation of natural gas thinning compressor lubricating oil got me intrigued. Have you ever torn down a Davey and noticed any significant wear that could be attributed to oil breakdown?
Karl

[cowboy]

Re: daveys

hi carl no I have not had any problem with hydrocarbon contamination that I know of. but keep in mind I run most of my compressors for extended times and the oil temp gets up to operating temp and will cook most of that off. If you have a lot of short runs it is like driving your car 1 mile each day your oil will become contaminated quickly as the oil never warms up.as far as oil pressure some people are running external oil pumps. as far as oil breakdown yep as to what has caused it I dont know cheap oil hydrocarbon contamination never bothered to change it ?

[karl]

Hi Cowboy,
Still fiddling around with my daveys in an experimental stage. I haven't had much free time but last week I
set up a jackshaft with two sets of pulleys so my davey/eagle spins fine at super low speed with a 5 hp electric motor.
As it built up pressure the third stage head gasket was leaking enough I couldnt't build up more than 1800 psi so I ordered one from Bargain Marge (actually her daughter) and will resume testing next week.
Oil pressure seems fine even at low rpm.

I am glad Bargain Marge still has parts as I would be hard pressed to find the right grade of aluminum and turn it on the lathe to the proper profiles to make a replacement for anywhere close to the $40 bucks it cost to get one ordered.
I do have a few questions for you,

#1Can you tell me what Davey specific parts you need to keep on hand as you do routine maintenance?

#2Do you get away with reusing the head gaskets after cleaning/lapping valve surfaces?

#3Do the valve springs seem to last for the life of the compressor?


Thanks,
Karl
Thanks,
Karl

[karl]

Hi Cowboy,
It turns out my third stage head gasket was leaking due to the third stage pressuring up to the same pressure as the fourth stage until it reached 1800psi at which pressure the Variable frequency drive shuts down the motor due to it drawing excessive current.
I did replace the third stage aluminum head gasket and it holds 1800 psi no problem and the third stage valves don't seem to leak back into the second stage at all.

With the fourth stage running at identical pressure to the third stage it seems the fourth stage intake valve is not sealing. I pulled the fourth stage head and valves and found the copper gasket under the valve had some hairline cracks in it so I made a new copper gasket out of .030 copper sheet, the intake valve plate (looks like a washer) had significant indentations from the valve seat so I lapped the backside of the valve plate flat on a granite plate with fine grit sanpaper and re installed it upside down thinking I would get a better seal.

Even after doing this it appears I am still getting absolutely no seal at all so I am hoping you will offer your experiences cleaning, overhauling, or replacing valves, especially the fourth stage.

I did end up turning a new aluminum fourth stage head gasket on the lathe and it sealed well.

The troubleshooting guide in the manual advises replacing the valve assemble under these circumstances. Do I need to hope bargain marge still has fourth stage valve kits for sale or is there a DIY cure for this?

Thanks,
Karl

[cowboy]

carlcall me 4238711106 yes you can rebuild the valves we do we lap the plates to within a part of a thousandth of flat the only part that is hard to find is the springs and that is high on my to do list I have been in nicarauga for the last three weeks got back today and will be home Friday. I think you have a bad valve in the 4th stage seal it is not a flat washer so it it sounds bad I have some new ones

[karl]

Hi Cowboy,
Tore down the fourth stage one more time and everything in the valve assembly looked absolutely perfect. I started looking at the miscellaneous hoses from the interstage traps and realized there is a hose running from a big supplementary coalescing filter to a remote solenoid valve that blows down all the traps when the compressor shuts down. It turns out this was backfeeding 4th stage air to the third stage. After removing that line the compressor easily pumps up to 4000 psi.
Since this is an Eagle/Davey electric driven compressor it has mostly the same hardware as my gasoline driven Davey but configured much differently. The previous owner(s) customized it as well so I need to do some more reverse engineering to figure out what is working and what is not.

Good news it pumps fine running at very low rpm so I will keep tinkering on it as I get time. The ultimate plan is to set it up to loaf along at whatever rpm will produce 5cfm and hopefully be far quieter than the coltri or bauer and likely run alot longer between service intervals.

The gasoline davey I have works perfect except that the wisconsin v4 makes such a racket that I can't ever picture running it for long if I am in earshot. I hate to part it out just to keep the compressor head but I don't picture anyone willing to pay me enough for the complete unit to justify keeping it together should I want to put the compressor head into service as an electric compressor after I get the bugs worked out of my "beater" eagle/davey test unit.

I don't recall the exact numbers but bargain marge would sell me a used davey compressor head that had been taken out of service for somewhere around 1200 shipped but if I sell the wisconsin VH4 and keep my 20 total hours davey compressor head it involves a lot less money changing hands and probably saves me money in the long run.

I'll continue updating as I get time to figure it all out.

Now that the compressor is pressuring up I am reassured that lapping the valve plates is as straightforward as I had originally hoped.
Thanks for the input,
Karl