SS3L3 to T30 2545 pump?

[g13092]

I've had an IR SS3L3 from Tractor supply for about 10 years, working pretty well until recently. The service breaker began tripping at start sometimes. Troubleshooting revealed the unloader wasn't working. After replacing the pressure switch / valve assy, start up failures occurred less frequently, but weren't completely gone and didn't stay infrequent. Next, I had the motor refreshed (mainly new caps) and checked by an old school motor guy. That didn't help. Recently, I recognized that if the pump stops 'mid stroke' (neither piston is at TDC/BDC), it requires a lot of torque to turn the flywheel by hand (both with and without the belt). Pulling the pump apart, I found some score marks between the pistons and cyl block. I think the pistons or bores have gone out of round, biding when they warm up. The problem is worse after the pump cycles than from a cold start. I think the pump may have overheated when left on with an air line leak, leading to this demise. Unfortunately, I don't have tools to measure correctly to confirm, nor can I find specs / tolerances (piston to bore clearance, etc) for these pumps.

All that is to say I have a decent tank and motor, but no pump head. I'm certainly not putting another SSL3 pump on this thing. One idea is to get a ****** "3hp-class" replacement pump from hobo fright and keep on trucking until that blows up... But, a guy nearby has a T30 2545E10 head for sale. I'm wondering if I can adapt it? I don't need 175 psi of the T30 nor any more flow than the SS3L3 (~11cfm at 90 I think, maybe 125). Maybe it can run slower with a tiny pully on the 3hp motor from the SS3L3?

There's quite a few nice threads here about re-pumping dead compressors, but I can't seem to find any details on how to figure the torque or pully sizes needed. Is my g00gle fu that bad? Maybe I am insane?

 

[Jswain]

Quick google search says 7.5-10hp motor so I do not believe this is going to work for you for multiple reasons unless you upgrade the motor.

Second problem will be speed, your motor is likely 3450rpm and the new pump likely normally takes a 1725rpm motor. For you to gear down your motor to the same speed you will need a very small pulley which I doubt will have enough grip to make the torque needed to spin the pump without slipping...

 

[g13092]

Current motor is 1725 3450 rpm with ~4" pulley. All the searches I found also came up with these at 7.5hp min. I wondered if the hp is really needed to achieve the high pressure and flow. Since I don't need the max of either parameter, maybe I get enough running it slower?

 

[strutaeng]

You don't have enough motor. I've got a Frankenstein air compressor with a Curtiss pump. Spec on the pump was 7.5-10HP. I tried to run it with a true 5HP motor and it would trip the overload on the magnetic starter. It's a single stage pump.

I wound up getting a 10 HP motor, but pulley reduced still to the lower end of the minimum RPM. I think it puts out like 22 CFM or something like that. I only fire it up to spray paint as I've got smaller compressors for most other tools.

You'll burn up your motor with that pump, most likely. Is your motor those special SPL or whatever they say on the HP rating? I think those were like 3HP based on amperage draw?

 

[g13092]

Thanks for the input,folks.

I double checked, it's a 3450 motor, and it is a SPL rating. The whole unit is advertised as 3hp... Ok, the T30 is out unless I find a motor.