Robinair VacuMaster Economy Vacuum Pump – 8 CFM

Have used a half dozen pump brands over the years. Whether made in USA or China, most are garbage. This 2 stage 8 CFM unit works great. It works so well I bought 3 more (deal with parallel multistage compressor systems). My customers have bought them too based on my recommendation, and are happy with product.

I did lose a leg shock absorber when pump fell 4 feet from a shelf on the truck. Pump still work fine.

Someone complained about pump not starting when turned on. This is a common problem with vacuum pumps, especially when pump oil is cold and happens to me every winter. It is not pumps fault but basic physics. Crack seal where hose connects to pump so pump does not have to start against low pressure and thick oil. Once spinning reseal and pump will work fine. If pump REALLY cold, it is probably not going to start at all. You can heat pump with a propane/Mapp gas torch to heat/thin oil. If this concerns you at all, do not do it.

Some have complained about misting. It moves 8 CFM a minute in the beginning. OF COURSE you are going to get mist on any significant system! If you do not want mist, restrict flow until you ger a fair vacuum, but time is money for people who buy an 8 CFM two stage pump. Mist is the tradeoff for pulling a fast vacuum.

One last point to make. It is very conmon to not get deep vacuum. Happens all the time. It usually means your system or gauge setup has a leak. It can also be caused by an uncalibrated vacuum gauge, your pump oil being dirty, or you have an improper oil level. All 4 of my pumps still pull a VERY deep vacuum when deadheaded and checked against an accurate gauge.

I’ve had this pump for a few months and it works wonderfully. I use it only for degassing silicone rubber prior to making molds. One thing I would strongly recommend is reading the manual carefully prior to use. I believe a lot of the negative reviews on this pump are from people who did exactly the opposite. The pump comes with 2 bottles of oil; I did not need to use both of them. You fill the pump with oil until it reaches the minimum line, then run the pump until it runs smoothly. Then I put the rest of the first bottle in and haven’t changed or added more since. This is a strong pump (2-stage 8CFM) so you will get small oil misting but it’s nowhere near as bad as the negative reviews say (they probably maxed the oil level before the pump was even turned on for the first time). I use the pump in my garage, and attached a 3-foot 0.5″ EPDM rubber gasoline hose to the oil exhaust and directed the tiny bit of fume out the window. I even went outside to check how much mist was coming out and saw intermittent nearly transparent puffs; nowhere near the “heavy mist” that some people are describing. As for vacuum, I get a solid 29 on the gauge of my vacuum chamber, but I also live in PA where the altitude is around 728′. The higher your altitude, the harder it will be to hit 29. All in all, this is a really great pump for the price and does exactly what I need it to do with no issue at all. Glad I ignored the bad reviews and gave it a chance.

P.S. What convinced me to ignore the bad reviews was the user manual. It is freely available online (check Robinair’s website) and it directly outlined how to avoid all the issues the negative reviews were mentioning. Following the manual personally avoided every issue, which is why I am convinced those negative users did not read it before use. I do recommend buying the EPDM hose, even in a well ventilated area. 3 feet of it cost me < $5 at the local auto parts shop.

I have been using this Robinair vacuum pump (15800 VacuMaster) for automotive AC work at home fairly regularly (approx: 25 – 30 times now) since I purchased it through Amazon.ca Feb 2015.

– So far this vacuum pump has worked flawlessly for me with no issues at all.
– It’s reasonably quiet compared to other cheaper lower CFM vacuum pumps I have used in the past.
– It does its job quickly and smoothly as it should since it is an 8-CFM two stage pump.
– The oil level indicator window is easy to see and judge proper oil level and cleanliness.
– The oil drain valve is located in a good position for quick and easy draining as advertised.
– It’s a sturdy product that is clearly built to last.
– At this point it gives me piece of mind knowing it’s a quality product and it’s ready to go for me anytime I pull it out for use.

Not much else I can say about this pump except in my opinion it’s a good investment if you are looking for a worry free quality vacuum pump that should keep working for you for years to come as long as you take care of it and change the oil when needed.

I hope you found my review helpful.
Rick…

This review is not so much about this product as much a reflection of Robinair’s business practices through online sales. I have three of their products previous, two two stage 3cfms and this was going to be my second 8cfm. I was buying it because I love the power my 8cfm has over the smaller pumps while being not much louder to operate. So I ordered this vacuum excited to add it to my family of pumps.
When it arrived I noticed something strange. It had thick dark golden oil in the oil sight, right out of the box. I flipped through the instructions (i have never seen this before in a “new” pump) and sure enough in nice bold dark print the Robinair Owners Manual states “item ships without pump oil” and to add pump oil before the inital use of the pump. This residual dark oil freaked me out mostly because the oil Robinair itself sells for use in its pump (and the only oil I use) is almost perfectly clear. The oil in my pump looked more like honey than pump oil. So i drained the pump and refilled it with the new robinair oil included with my pump and tested the pump on my chamber for barely an hour. The pump worked well at first pullling the vacuum to close to 29, then as I let the pump run I noticed to hear a whine or stress sound coming from the motor of the pump, and then it just up and died on the stop, probably within 65 minutes of me pulling it out of the UPS box. Now the reason I wrote this review is because I feel that after examination of my pump, the weird gunk in it when they shipped it to me, and its performance compared to my funcation 8cfm pump, I concluded that this “new” pump has seen way more wear and tear than my old pump. Noticeably after running such a short time the “new” pump has already given the pump oil a burnt smell. Not only do I find it insulting that Robinair thought they could trick me by sending me a pump that has clearly been used before, the motor was practically on its last breath and now after waiting for a pump for a week now, I get to stare at the broken piece of shit on my garage table while Robinair takes 10 DAYS to send me a new one (they obviously do not care at all about the embarrassment to their company that comes with a transaction like this. When I have order from other vacuum vendors, any loss of pressure or function of their product was always replaced IMMEDIATELY (overnight or at least two day). Robinair doesnt even have the decency to admit theyre tried to sell me a used pump under the guise of “new” and I certainly will not be ordering another product from them in the future. I will instead go to companies like YellowJacket who may be more expensive, cause i know on arrival i wont be receiving a deceitful item and if I ever had an issue it would have ben handled much more gracefully than simply making me wait almost three times as long as I wanted to for my product.