[Dynomatt]

I recently bought a 7.5 h.p. air compressor with a bad motor. It's a Lincoln brand with a Dresser two stage V2 pump. This was a find for me since my last air compressor's pump, (also 7.5 h.p.) ended it's life with catastrophic failure. Someone however, decided that this verticle tank Lincoln was too much to move assembled. They broke it down to it's 3 major parts and used bolt cutters to clip all tubing at the fittings. My question is how was the centrifical unloader plumbed originally? It has (3) 1/4" fittings, the tank has (3) 1/4" fittings and each cylinder head has (1) 1/4" fitting each. I understand that a crankcase vent works into all this too. The pressure switch will be starting and shutting down the motor. I have no plans for a continuously running system. I know a solenoid and timer venting to atomsphere on the output of the second stage would be easier, but I'd like to try the centrifical. Com pair sent me a complete break down of the Dresser 440A but no external plumbing. I can find anything on Lincoln.

[cashmoney]

I am partial to the "Quincy 325" but that "Dresser 440" is probably one of the best pumps ever designed. New it is worth over $3,000. Be sure to keep the oil fresh as they are prone to high pressure wrist pin bushing failure late in life like most other makes of pumps. Bar none the " Dresser" is an almost flawless pump and to answer your question the two head unloaders were connected together with a T, leading to the top flare nut fitting on the small box connected to the oil pump/bering carrier. If you have any questions "Le Roy Dresser" is now owned by "Comp Air" and parts although very expensive are still available. Hope I answered your question and congradulations on your find.

[killerformula]

I don't want to raise any concerns here unnecessarily, but cutting off tubing with a bolt cutter seems a little barbaric. You sure this thing wasn't stolen?

K

[oldred]

Originally Posted by cashmoney

["Le Roy] Dresser" is now owned by "Comp Air".

"LeRoi" Dresser will work better,


I have to agree on that pump quality as those things are industrial duty to the max!

[oldred]

Originally Posted by cashmoney

I am partial to the "Quincy 325" .

My old Quincy is over 40+ years old and still ticking, it served me well all those years and even at that I acquired it used, but almost new. From the beginning when I started my welding business it was gasoline powered on a welding service truck where it outlasted two engines and a tank. A couple of years before closing shop it was removed from the truck and powered by a Baldor electric motor for use in the shop until I sold out, that old pump and my hand tools is all that I took with me when I left. It resides today in the back of my shop where it quite effortlessly keeps my 60 gallon tank filled to 150 PSI for use in my retirement years.


This old pump is, like me, starting to finally wind down although after more than 40 years of mostly outdoor use and untold numbers of running hours it is still very much serviceable even though it has never been rebuilt! It has during this time needed a couple of minor repairs such as fatigue related broken lines, etc but never anything more major than that. Yep I like Quincy pumps too and I have a good reason for doing so, mine is far from the only one that has seen this kind of service and is still ticking!

[cashmoney]

"Killerformula" you would be surprised, people actually junk pumps like the Quincy, Dresser, Saylor Beall etc. that were passed down for generations simply because they can buy a shinny new piece of junk at Home Depo for the cost of a rebuild. Old pumps like the Quincy and Dresser are now sought after and used in the oil and gas industry for natural gas compression and air balanced pump jack operations where absolutely no expense is spared. They are expected to run all day all night 24/7 where every day of down time costs up to $4,000. "Oldred" dose your Quincy 325 have acorn threaded valve caps on the head, several small bolts holding down a small octagon cap/plate on the front of the oil pump, and square fins on the intercooler tube. If so it has a vain type oil pump and I am familiar with that model as well. It is nice to know there are people still out there that appreciate "old school " engineering and design.

[oldred]

As part of my welding and mining equipment repair business I set up and sold quite a few systems, mostly on service trucks that were gasoline or hydraulic powered but several shop systems as well. The Quincy was by far the most popular unit and quite a few of the ones we installed even as far back as the 70's are still running. I know what you mean about some of those old beasts getting scrapped and it is almost painful to see one in a scrap yard which I did not too long ago, it was not locked up and certainly was rebuildable and like you said I have no doubt it was replaced with a shinny new piece of junk, probably from China, and the owner had no idea what he had thrown away!


I see those things sitting in Lowes/Home Depot/Tractor Supply and I see the ridiculous performance numbers most of them have plastered all over them and I just know how long one would last in a real work environment, that is even if they could keep up with the air flow they claim!

[cashmoney]

Rolleys,
Not only the rediculous claims but the heat generated and condensation created in air lines on the china pumps. I do not care for the reed type valves that crack after three years. I have disected many pumps and by far the Quincy has the best valve and unloader design. The Saylor Beall has the best pressure lubrication needle bering wrist pin and intercooler design. Some Champion and the Le Roy dersser also have huge valves too. Man they just don't design "cold War era" stuff like that no more. Thank god most are still available.

[oldred]

Cash, I see you are new here-WELCOME!

You are going to find there are many compressor questions being asked almost daily and your obvious expertise would be a welcome addition here. The home shop compressor companies have done such a good job spreading their compressor (mis)information, sales tactics and just plain BS in an effort to sell those tiny pump over-size tank wonders that most who come here seeking advice are thoroughly confused by it all. "Peak" HP ratings, "Tank assisted" CFM ratings, etc has caused a lot of confusion but things have been getting a lot better lately.

[cashmoney]

Thanks Oldred.
I have dabbled with compresseors of all shapes and sizes. I have learned the most robust and efficant designed pumps were produced in the 70's and 80's most of which are still in prodiction. This is because they operated at low speed (approximately 800 rpm). My advise to the group is if you are ever lucky enough to find one of these old pumps that is actually affordable, be sure to confirm with the manufacture if parts are still available referencing information from the name plate. My claim to fame was when we joined a gienormous "Le Roy Dresser" 660a (full pressure lubricated to the upper wrist pin piston type compressor pump to a properly pully matched small in comparison 5hp "Baldor" motor on an 80 gallon 200 psi tank. This unit ran sooooo cool you could actually hear the pistoons independantly popping. It even produced more cfm than a conventional equivalent. Despite a slow speed the oil pressure was at factory specifications. It broke my heart when the customer picked it up. Take care Oldred....