Old CV Power unit - what to inspect

[panofan]

So I bought a used CV unit - before I start the install, I am wondering what I should inspect. The previous owner said it wasn't used very much - and it does look clean. The inverted filter (it is a beam unit) looks quite clean - I'll still vacuum it out. The unit is in really nice shape but is probably from the 80's.

I'm guessing I should look at the carbon brushes to see if I should just start with replacing them?

Other things I'm thinking of are the gaskets - around the collection bin and motor - prob couldn't hurt to get new ones, but how do you know if they are still good / sealing well?

Anyone have an idea of the age? The model is beam 294. Also, does anyone know how to decode the serial number to determine date of manufacture? I've contacted beam to ask, but haven't heard back yet.


Thanks for all advice and insight!

 

[centralvacs1928]

Check the filter. Remove it and hold it up by one layer so the other layer hangs down, then feel for dust trapped inside. If the machine hasn't been used much there shouldn't be a buildup, but this two-layer filter is the weak point of older Beams, and causes a lot of performance loss.

The "bean bag" sewn into one layer is supposed to be there; you are looking for a buildup of fine dust between layers. If all you can feel is the fabric, you're good. Otherwise, the best fix is to buy a new (single layer) 14" filter, but I've had good luck machine washing the older filters. Usually you have to do it twice on a gentle cycle, then let the filter air dry.

The Beam 294 has a motor that should give you around 130" sealed vacuum, and around 70" working vacuum (at a 5/8" orifice). The latter is difficult to measure without a special tester, but is the best indicator of how much performance loss the filter is causing. The sealed measurement only tells you whether you have leaks in the unit or tubing system.

That motor is a workhorse and will run forever. Difficult to change the brushes because the cooling fan prevents removal of the top cap (so you have to use an angled screwdriver and some swear words), but with new brushes that should work for decades.

 

[panofan]

Awesome - thank you so much for the reply - you made my weekend!

I have a few months until the reno is underway and I can install the tubing - so this gives me a few things to test and play around with

Any idea on what age range this would be? The beam logo on it looks like a lower case 'b' - v.s. another 294 I see now on ebay that has the beam logo which looks like an inlet vale.

Here's a picture of it:

 

[panofan]

So, reviving an old thread.

I installed the unit, piping, inlet valves, etc. I managed to make it work with only 90's behind the inlets and all 45's everywhere else, using wyes and not tees to join to the trunk line, etc.

It is awesome! A bit loud (even with a muffler and vented outside...) - but great power at all the inlets and this thing spins a turbo brush like it is no one's business - even on plush carpet. The turbo is just for fun / easy quick cleanups with the non-electric hose - I did buy a Riccar made electric kit.

I have new carbon brushes purchased, just need to check the existing ones / potentially install them (definitely a project for the new year, maybe next summer).

One question though - without knowing what "normal" was for the machine, how would you know when you would need to replace bearings, etc?

(I did find markings - this does in fact have the lamb 116119 motor - and crazy that 30ish years later, the motor is still made and can be purchased!).

 

[ultralux88]

I replaced the motor in a unit similar to yours (a 190 with a 7in 2 fan motor) that the motor had died in. The guy brought the unit in for us to work on, I also cleaned the whole thing up, took the filter out and had my boss blow it out really well, it came pretty clean, and was running great when I was done. He was happy with it.

 

[centralvacs1928]

Sounds like you did an excellent installation job! The piping should give you no trouble now no matter what you vacuum up (within reason...)

As far as the motor, I think if you were to use it until you had an issue, you would be very surprised how long that took. The system in my home uses the peripheral exhaust version of your motor (116118), has had an incredible amount of use, and still keeps on going. Your motor is also one of the few that can almost always be run until the brushes are completely worn without sustaining commutator damage. Pop the new ones in and you're all set. The bearings should be good forever unless they've seen damage from moisture or heat.

One way to find the age of your machine is to look for the date code stamped on the motor, in green or black ink. The last two digits are the year. I believe your machine will be late seventies or early eighties, since they started using the newer logo sometime in the mid-eighties.