Thank you for the info. This is helpful, but since the I don't know how powerful the compressor it is a wash on deciding on what kind of pulley I need. I'll just buy another air compressor out there. The one I own know is a hack job, I won't be putting anymore money into it.

However, I'll keep it the compressor for a spare or sell it. Same goes for the tank.
I'll also swap the the motor to see if the compressor is even worth keeping.


There's another one in much better condition and it isn't a hack job, it's a stock champion 2hp air compressor.

I'm going to upload some pictures of it very soon, i'll step outside in a sec.

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

I think you are going the right direction
but I would never again buy anything less than five hp for a shop compressor..
just my experience with smaller ones......check to see how much air tools use..
a LOT and some require a high pressure at the same time...
good luck

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1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/showthread.php?t=156207&highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

What would you like to be able to do?
Depending on what your plans may be, various air tools consume air by CFM, and if you choose tools that consume a lot, get a compressor that is up to the task. Otherwise your "quality time" with your car will be squandered as you wait for your undersized compressor to "catch up".
Using tools are to get tasks done faster. If you are waiting on your compressor all the time, you may as well use hand tools.
Smaller CFM output compressors are for smaller tools, mainly for intermittent use. Larger CFM output allows the use of more types of tools, including sanders, DA sanders, paint guns and the like.
I have had an undersized compressor for over 10 years, bought new. Too small for most jobs I ENDED UP needing to do; just wishful thinking, I had to pass.
My next compressor will be over 10 CFM capacity with a 60-gallon tank- and aside from sandblasting ships in drydock, I will be OK. For automotive, there is such a thing as "NOT ENOUGH" and "TOO MUCH"- it's difficult to do fine feather paint sanding on a fender with a horse of a "bull grinder" that would like to snap both of your wrists when you hit the trigger.
My advice, for what it's worth- consider the CFM rating of the tools, THEN look for the compressor. The compressor will take up room-make sure it gets full use and not wind up just being something that is in your way.

Cheers!

snapped_bolt

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'81 240D For now, a good place to borrow new parts
'80 300TD Probably will be put back into service!
'79 240D BACK IN SERVICE SINCE 09/16; limited use, oil leak. Guide pin r/sealed/replaced. Still a leak. Front crank seal....

Amen...
It is amazing how much air is needed for things like a 17 inch straight line sander or a palm sander used with water.... and it has to be AT the tool... friction and line size and length can mess up the situation..

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/showthread.php?t=156207&highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

I've had a Craftsman "5-hp" and "7.1 CFM @ 90 psi" 20 gallon compressor for almost 20 years. I put ratings in quotes, because I know it's complete BS that it is 5-hp or delivers 7.1 CFM. I think the "claims" posted on compressors have gotten a bit more honest in recent years, but overall I still think they are totally bogus. The tools also lie, add at least 2 CFM for any sander or paint spray gun as to what it will really consume in actual use.

So...get as much as you can afford, and are willing to deal with in terms of rewiring your house demands. For me, I wasn't staying in my present location for much longer, so I bought a second mediocre compressor that also lied about its output. I have one running on one breaker in the house and the other one running on another breaker. They both feed air into the same line with a 3-way splitter that harbor freight sells. From there the line goes coalescing filter, and then a 1-gallon desiccant dryer and then there is a 10 gallon piggy back tank (only want clean dry air going to that tank because there is no drain on it). I keep the regulators on both compressors set so they never deliver more than 125 psi, which is the "limit" of the piggy back tank. The system is 1/2 lines until the last ceiling mounted hose real which is 3/8 and 50 feet, and has a total tank capacity of 60-gallons.

Overall, it works pretty well, painting isn't an issue, DA sander is my biggest consumer, and if you keep going with it the compressor will keep running too, and sometimes they both kick in. The newer compressor has a tank limit of 155 psi on it's 30-gallon tank, so it tends to run much more, as it kicks in at 110 psi, and the old Crafstman doesn't kick in until 100 psi, and it kicks off at 125 psi. Is it ideal? Nope, but it gets me by as a hobby level user.

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1983 W123 300TD US spec Turbo engine, with Euro bumpers and manual climate control, and manual transmission.

This is spiraling out of control for no good reason. ( and not because of the compressor you bought )

From what I recall of the pictures, the compressor in question had a very small pulley on the motor relative to the pump. Please measure the OD on both.

Where did you find a spec that this pump takes 2 HP? Is the motor data plate stamped 1/2 HP? Also please list the RPM of the motor.

The capacitor that failed, was it in a plastic or metal can? When start or run caps fail they do not damage the motor directly, any damage only occurs if the motor is trying to start and does not trip a breaker / thermal overload.

Does this compressor have an unloader? On smaller compressors this is a small ( 1/4" OD ) line that runs from the compressor head or tank check valve then to the pressure switch. This line is usually on the side of the pressure switch and is in addition to the tank pressure sensing line.

When the compressor is up to pressure and stops, the unloader line relieves pressure at the pump so the motor isn't starting under a high load. ( Another trick when dealing with limited power, add a manual valve to the unloader line and leave it open until the pump comes up to full speed. )

This can still be made to work, it is possible to run a " 2 HP " pump with 1/2 HP motor, it will just put less air because the pump speed will need to be lowered.

This setup is less bad than you think.

Air is a very expensive 4th utility ( Water, nat gas , electricity, compressed air.) Nearly all the expense of compressed air is the electricity to turn the pump. Equipment and maintenance costs are minimal by comparison.

Staging compressors is commonly done in industry if wildly varying air consumption is expected.

Tank capacity is your friend, the less starts per hour the better in terms of energy consumption. Over compressing air ( to a higher pressure then regulating it down . ) gives you artificial tank capacity at the expense of energy to power the pump. For home use this is fine, however in industry , it is poor planning.

Welp, the motor is completely shot, the armature has been melted solid, no valleys.

I was going to buy another motor or compressor but, both Craigslist sellers aren't responding.


This one looks interesting.

https://norfolk.craigslist.org/tls/6214971956.html

__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

You don't need junk like that to do what you are going to do. Buy a new one for $99 from HF. You will be glad that you did.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Armature as in the rotating portion of the motor? If so, this smoothness is entirety normal for an AC induction motor. Please post pictures of what you think is bad.

And, read my recent post about needing more info.

On what basis do you consider the just listed compressor junk?

Dayton is the house brand of WW Grainger used across many products, their electric motors are very popular for general use industry. ( Baldor is one of the really HD brands however )

This compressor is a real 3/4 HP as opposed to the 2 HP rated generics. It is also reconnectable to 230 making it a good value. A pressure switch isn't to fix the no shut off expensive. ( assuming it is actually getting to pressure and beyond )

Regardless, the compressor our guy has needs attention first.

Ok hold on one sec

__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

On the 2nd picture especially, aren't there supposed to be little individual copper wiring visible, not just a blob of molten looking metal?

Attached Thumbnails

   

__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

It is a matter of 'horses for the courses'. The OP wants to do leak down test and some suspension work. It does not make sense to buy an used one of unknown condition, though it may be name brand, fix it up ( if it is fixable ) and do a simple job. It looks like the OP is spending a lot of time to find one, fixing it with new parts, testing it and then hopefully to use it. It is not an effective way to spend one's time and money. The real engine/valves testing job is push back. If it were me, I would just spend the $100 on a reasonable hobbyist compressor from HF and get the job done. My $0.02. The OP can do what he likes, his money and time.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

This is completely normal for a " squirrel cage " AC induction motor. The rotor ( arrmature ) is built up of slotted flat plates then aluminum is poured in to form a continuous winding. After pouring, the OD is machined to size.

The stator windings ( in the housing ) induce current into the rotor, the current flow in the rotor sets up an opposing magnetic field causing the rotor to turn.

Not all motors have actual windings in the armature / rotor found in DC ( starter motor ) , universal and some long obsolete AC motors.

Please read my other posts and reply to the very specific questions if you want to solve this problem.