Help with DeLaval 75

[longbeard]

I purchased a Zero vacuum tank last year and the owner thru in an old Delaval 75 pump (which I didn't expect).

Since it was a limited sap flow last year I didn't learn too much about vacuum, but the question I have is I don't see how to control the vacuum pressure. The guage on the tank would go above 20 " but I gather that is too much and may burn the pump up? So I cracked an unused valve on the tank to let a bit of air in and lowered it to about 15 " - does this method sound O.K. or is there a better way to control it at the pump.

Thanks

John

[sugarmountain]

You need a vacuum controller. You can buy one through any maple dealer. They consist of mainly a weight on a slide like a lever that allows the pump to only open it up so far depending on how you have it adjusted. Look on lapierre usa web sight. What they have is in my opinion the most simple design.

[maplecrest]

the valve will work but you need to watch it. will change with the day. humidity raises problems. as does freezing rain.they will freeze shut.but at lower vac like 15 would not be a problem. the higher the vac the colder it gets and more problems you would have.or spend the money and get a regulator. i never had good luck with them they freeze too.if outside. in a heated room they work great.