Recommend a good roughing pump repair/refurb company

[MSCHemist]

Does anyone know of a good vac pump repair/refurb company.

I am looking to buy a refurb E2M2 or RV3 to replace the horribly back-streaming E2M1.5 on a 5973 diff system. We've ordered from Vac-tech before but haven't had too much success wither their refurbs.

[James_Ball]

Does Scientific Instrument Service (SIS) still do refurbs? Been a while since I ordered from them but they may have what you need.

[LALman]

I swapped the E2M1.5 that came with my 5973inert turbo system for an E2M2 I had in the lab and its a far better and quieter backing pump.

I second about SIS but I also buy rebuild kits for my E2M2 and E2M1.5 from Capitol Vacuum. Their site says they have some refurb Edwards vane pumps but they don't specify which.

[MSCHemist]

Thanks according to spec the E2M2 is supposed to be noisier. The E2M1.5 is listed as 42dB(A), E2M2 52dB(A), and RV3 48dB(A). It looks like the E2M2 has only a slightly higher pumping rate (1.5 vs 1.3cfm for E2M1.5) but a much lower ultimate vacuum pressure 7.5E-4 torr vs 1.1E-3.

I may try to repair the E2M1.5 myself and keep it as a spare. It is hard? I assume the problem is in the antisuckback valve which is just a spring trap below the intake port. The reported problem is it back-streams oil badly mainly when starting (also smokes a bit) and it gets worse when the oil is above the min operating line.

I have to totally clean out the diff pump and hose as it was full of roughing pump oil.

[James_Ball]

We used the M1.5s on the 5973 units we have but all died far too soon. I even placed them on the floor instead of tucked up under the MS and it didn't help with the life of the pumps. We had several M2s left over from the 5995, 5970, 5971 and 5972s that were replaced by the 5973s so I just reused those. None of the M2s have ever been refurbed and a couple have been here since before I started working here in 1991 and are still going strong.

The db of the M2 may be higher, but the frequency of the sound is lower so it is not as noticeable as the M1.5. They also run cooler which is why I think they backstream less and live longer. One of the 5975s we have came with the small Pfeifer pump and it would fill the line with oil half way to the turbo pump even with the rough pump sitting on the floor below the MS. That now has an M2 on it also. One note, put a regular plug on the power cord and plug it directly into the wall, because the motor on the M2 does pull more amps than the M1.5 and best to not overload the breakers in the MS. You have to unplug them when you want to vent, but otherwise everything else works the same.

[LALman]

Its also nice when you break vacuum to still have the roughing pump keeping a partial vacuum until you actually open it. Also, makes pumping down easier. You get the rough pump happy its a lot easier to bring up the turbo separately.

Both pumps are pretty easy to rebuild. The refurb kits are ~$200. I use a couple of cookie sheet trays. There will be a lot of slippery oil, its quite messy. You drain out all the oil you can. You just disassemble, the diagrams are fairly clear. The hardest part is getting out the motor shaft seals. Get most of the oil off with paper paper towels but unless there is corrosion you don't need to solvent clean them. Then you reassemble while swapping in all the new parts. Have some fresh oil in a dipping pan so you can keep it lubed up as you rebuild. It will be easier to slide the parts together and easier on the assembly when you start it up.

[MSCHemist]

One note, put a regular plug on the power cord and plug it directly into the wall, because the motor on the M2 does pull more amps than the M1.5 and best to not overload the breakers in the MS. You have to unplug them when you want to vent, but otherwise everything else works the same.

That is the plan I also heard from a person that fixes them that he has seen cases where the pump fried and destroyed the MSD electronics as well. I would think the MS fuses would protect it but apparently not always.

[James_Ball]

One note, put a regular plug on the power cord and plug it directly into the wall, because the motor on the M2 does pull more amps than the M1.5 and best to not overload the breakers in the MS. You have to unplug them when you want to vent, but otherwise everything else works the same.

That is the plan I also heard from a person that fixes them that he has seen cases where the pump fried and destroyed the MSD electronics as well. I would think the MS fuses would protect it but apparently not always.

The fuses will protect from an initial surge, but when run slightly over limits for long periods of time, the extra heat generated in the electronics will eventually fry them.

[LALman]

I put an APC ~1350W UPS on my 5973inert and PC and network switches. I run the pump and the printer off the non UPS protected outlets. I think the 6890 is still on the regular outlet. The oven draws too much power. So my E2M1.5 was never tucked in there and running off the 5973 sockets. I have mine on the bench divider above the GC-MS. I'd put it on the floor but the vacuum hose is not long enough. It may be less DB but its a high pitched noise compared to an E2M2.

[MSCHemist]

I got an E2M2 and it is annoyingly noisy. It rattles/vibrates like an A/C or refrigerator. I called the company that supplied the pump and they said that is normal. The vanes spin freely under high vacuum. When I open the gas ballast a bit it quiets down because it is rubbing the walls. They explained the E2M1.5 rotates twice as fast so you can't hear the rattle. They said it may quiet a bit over time when the springs wear a bit.

Edit I think I am just not used to the rattling noise it makes compared to the Fan whirring noise the E2M1.5 makes.

[LALman]

The E2M2 will quiet down to a low rumble. The E2M1.5 got some of its shriek from how close the fan cover was to the blades. As it aged over 10 years, I was not sure if it was just improving or if I was loosing my hearing.

Some of the old printers had a recessed male socket cord. So, you can set up the E2M2 with that style cord and just pull it apart when you want to vent it. I think its handy to be able to leave the system under moderate vacuum after the vent cycle is finished. Also its easier to get vacuum started by initially using the roughing pump and then if that works, turning on the turbo or diff pump.

[MSCHemist]

Mine has a wall outlet plug with an on off switch on the cord which is very handy.

[James_Ball]

Mine has a wall outlet plug with an on off switch on the cord which is very handy.

I have one modified with that, the others we used heavy computer/printer cords that have the exact opposite fitting, as mentioned above, makes it easy to just pull it apart to shut down.

[JGK]

I've used American Laboratory Trading. https://americanlaboratorytrading.com/locations.php

they offer a warranty on the equipment they supply.

[twranger]

We've been buying our replacements from Innovative Vacuum Solutions. Slowly replacing our E2M1.5 as they get old with RV3, they are quieter and pull more vacuum. We tried refurbing the 1.5s, but they just start leaking again. The Pfeifers were even worse, we pulled those after a few years.

Oh, make sure you get the adapter for larger port on the RV3.