Gast Vacuum pump questions

[BeeRay Farms]

Guys,

Have one woodlot with about 300 taps that I think a little gast 1550 I have (new old stock) would do ok on. At very least it would be as good as buckets we have done on it and be less collecting labor. I am missing the jar filters/ mufflers on them that others seem to have, since I am putting a moisture trap on inlet side would I even need them?

My thought is to put about a 1hp electric motor on this with pulleys to make it turn at about 1800 rpm. I have a Johnson controls programmable 110 thermostat for setting up a freezer as a homebrew fermentation cooler, it has settable off and on points with a programmable differential. I was thinking of having it kick on around 34 degrees plus or minus 1 and having it kick off at 30 degrees plus or minus 1. There is a barn at neighbors property in the corner where tank would go so wouldn't have to do much other than a 12 gauge extension cord.

I know others have done these setups before. Wondering if since it isn't a huge pump in terms of draw if it makes sense to run multiple 1/2 inch mains into a manifold at releaser or go with like 2 @ 3/4 inch mains. This woods has about 5 "clusters" of trees 3 on one side of path and 2 on other, tank would sit at end of path. This particular property is very flat (Michigan), envious of those who have some slope and can get away with the 3/16 tubing...

Welcome to suggestions.

[Haynes Forest Products]

I think its a sound plan with a few exceptions. I would turn the pumps on early and shut them down after complete freeze up. Gast pumps can run dead headed so they are a great idea. Having a remote pump start with real time temp info and tank fill sensors tells me that there is no rhyme or reason to how and why sap flows when it does. I can tell you it takes only one big tree that gets some sun to start the warm sap flowing down the line to break up an ice dam on all hell breaks loose.

Your pumps need need protection so a good moisture trap is a must and one that will trap incoming moisture from the sap and a good non restrictive muffler and I can talk you thru that.

Now if I was some Fancy Smancy Dr in the maple industry that knows how to write down data and decipher the information and then throw the word REPLICATION around like a joint at a family reunion in Bolder Colorado I might be able to help.

Now if anyone is looking for a few Gast pump set ups I have a few pump with motor frame and 5 pump bodies that need rebuilding.

[BeeRay Farms]

So what is your recommendation in terms of the muffler? I have an idea for a moisture trap.

[Haynes Forest Products]

I went thru about 5 differant derivations of all sorts of things then I had a buddy make up some mufflers from my spec's

Go to Home Depot and get yourself a 4' section of 12" duct pipe, 2 end caps, 1 1/4 PVC glue to threaded hub and scrounge some course insulation. fill pipe with insulation, pop a hole for the hub in the end cap and insert hub. Secure end cap with screws and on the other end drill about 4 1 1/4 holes for the air to escape and secure with screws. If the pump is inside run about a 4' length nof flex PVC from muffler to pump . Glue the hose into the muffler hub. You will figure out the pump side.

When running there is very little air exhausted because you have one of the tightest system known to mankind in the woods because your GOOD. There will be heat so expect the PVC to get hot so dont go cheap on the hose. Point the exhaust in a direction away from the house BUT it will be quiet as quiet on a Gast pump can be. It will sound like a brand new Prius.

[BeeRay Farms]

Thanks for this advice. Next question, do I need any sort of vacuum tank, or will the moisture trap be adequate on the inlet side? If I understand right some guys use a portable air tank between the pump and the moisture trap to keep the pump from having to do as much "catch up" after the releaser dumps....

[Haynes Forest Products]

The tank will also accumulate moisture so plan on having a drain in it. Yes it will help smooth out the releaser dumps. What style releaser are you planning. The size of your moisture trap will determine what you want and need.

The word moisture trap is kind of misleading because it really is more of a device that will stop large quantities of liquid entering into to vacuum pump. Moisture with small traces of sugar......about 2% will enter the vacuum pump and over time it can build up in the oil and internal components. I really don't know what difference it would make having the vacuum reserve tank before or after the "moisture trap" The bigger the tank the slower the moisture laden air will move and have a better chance of coming out of suspension on the internal walls.

If your pump is a dry vane style it needs to be cleaned over time and can stick over time from the sugars. If its a oil type that exhausts is oil to the atmosphere those sugars will be somewhat washed away. Now if you recirculate the oil back into a recycling system the sugars will build up over time and the oil should be changed regularly.

[BeeRay Farms]

I have a single vertical mechanical I was planning on using for this. Was thinking of making something like a 4" pvc type "moisure trap". I have heard of some folks using a 10 or 15 gallon portable air tank as this reserve tank, most of those have a drain valve on them so that is a good thing.

Good advice on the sugars eventually making its way into pump and need for maintenance. Thanks.

[tcross]

i have had good success with using 4" pvc pipe and making a moisture trap with a racquetball for the float/stop. i actually have two of them in succession. i used to have only one and on occasion of a freeze up and a quick thaw, i'd get some ice mist sucked up into my vacuum pump. not a whole lot but enough so i had to change the oil more than i wanted. last year i put the 2nd one in and no issues what so ever. both mine are about 3.5' tall or so. i run a single vertical mechanical releaser and a bb4 rotatory vein pump. i also think the second moisture trap i put in helped with the recovery time of my releaser.

[maple flats]

If it is a BB4 pump you have a piston pump, not rotary vane. Piston pumps are positive displacement and will in a tight system, if in good condition give you 25-27" vacuum. I ran a BB4 on 225 taps this year and when the leaks were in check I got 25-27" all season. It will likely handle 500 taps, but I don't have the CFM specs to verify. Do not try to run at speeds higher than suggested. For proper RPM check with member "Windy Acres", he likely knows the specs for that pump. It is old, but a much better pump than dairy rotary vane pumps.
I change the oil in mine every 2 weeks, and I use synthetic oil.

[tcross]

Thanks Dave! i guess i'm showing my ignorance. i admit i don't know a whole heck of a lot about pumps in general. I also couldn't' tell you the rpms it's running at. i picked it up off a local sugar maker. he had been using it for the last 7 years -running 26" on 2000 taps with 2" wet/dry system. i don't have an issue getting 27-28" at the end of my mains. i only have 250 taps on them... two separate 1" lines. longest one is about 800' the other 350''. perhaps i should figure out how to check the rpm's. it gets warm, but never too hot to put your hand on. when the temps climb i put a fan on her. she's in my barn that stays 10 degrees cooler then the outdoors. I change the oil every week or 2 or so, depending on how the sap is running.

[Haynes Forest Products]

Most engines and pumps have a sweet spot and if you cant get a good read on the RPM's try this. with the unit up and running with a glove or shop towel cover the intake . Now dont let the rag get sucked insp fold it over about 6 times and cover intake. Run the engine up and down to where it sounds like its not over speeding and is getting good airflow. Now see what you have for vacuum. Will it improve with lower or higher RPM's ?

I was a novice when I started and assumed that wide open on the motor had to be better for the vacuum levels. Thurs out with a 9 HP engine just above idle was best for the pump also. Piston pumps dont rely on speed to seal the internals. Vane pumps need a certain RPM tp get the vanes to seal and yet over speeding hurts them because of the heat generated with less cooling air. Yes Gast vane pumps can be dead headed BUT that wont really show its true capability. Plus whit a oil vane pump you want the oil to lubricate the vanes against the drum surface and over speeding will cause them to hydroplane and not seal as well.