Delaval 73 clicking while running

[Starting Small]

I did not realize that I needed a check valve installed so I ran and shut the pump down 3-4 times without one and now I installed it. I changed the pulley (still hot to the touch though, cant hold my hand on it for more than a second or two, took about 45 minutes to get to that point), installed the check valve, tightened the belt and turned it on. Now I hear the pump clicking while it is running, something that had not previously happened. Is it something that I need to be concerned with? I am still pulling 27 inches, I just do not want to run it and further damage it. Not sure why the pump is hot either with the 3.5 inch pulley on the motor, running about 764 rpms according to a chart I found online. Could these be related or should I just run it and not worry so much? Thanks,
-Dave

[DrTimPerkins]

Now I hear the pump clicking while it is running, something that had not previously happened. Is it something that I need to be concerned with?

It is most likely just the metal gate of the check valve swinging back and forth. That's common and normal. If the pump has been off for a while and you turn it on you probably won't hear it for a short time because it's sucking enough air to stay open, but once it draws down the vacuum a bit there aren't enough air molecules moving by to keep it open all the time, so it clicks and clacks open and closed. If you get real close to it you can probably figure out where it is coming from....and that'll likely be from the valve.

The overheating is another issue. You'll probably either need to back off on the vacuum level, or will need to find a way to keep the pump cool. There are certainly people here that know that pump better than I do, so I'll let them reply.

[Starting Small]

Thank you, I will check it out today, I appreciate the quick response!

[blissville maples]

I have ran a vp 78, upon trying to run at 25'' my vanes were overheating sometimes sticking and slamming at intervals that changed based on how much my regulator was regulating vac. first year I took apart nearly a hundred times, every time I started it they were lodged in their slot so I would push them up with a screwdriver, put oil on them put them back in and good to go for day. after talking to delaval, they said by running at over 22'' there is very little air coming into pump overheating vanes causing them to stick. so I then allowed more air into pump, cut my vac down to 20'' and start up ran fine since. they are just simply not meant for high vac.

[Starting Small]

I have ran a vp 78, upon trying to run at 25'' my vanes were overheating sometimes sticking and slamming at intervals that changed based on how much my regulator was regulating vac. first year I took apart nearly a hundred times, every time I started it they were lodged in their slot so I would push them up with a screwdriver, put oil on them put them back in and good to go for day. after talking to delaval, they said by running at over 22'' there is very little air coming into pump overheating vanes causing them to stick. so I then allowed more air into pump, cut my vac down to 20'' and start up ran fine since. they are just simply not meant for high vac.
Good to know, maybe that will help keep it cooler as well. I will aim for 20 inches, thanks for the advice,
-Dave

[wildlifewarrior]

Hi guys,
How would you suggest reducing the vac without creating leaks? Slow the motor down?

Thanks
Mike

[BreezyHill]

Slower...much slower to reduce the vac and not intro air to the system.

Kevlar veins will expand when hot...73 is a steel vein pump. All even series pumps are Kevlar or the B word depending on the age.

A vacuum regulator will only introduce air to regulate the vac level so is a leak.

[mellondome]

Put a vac regulator on it. It allows air into the pump close to the pump... they are controlled by weights or spring / diaphram. You can set desired vac level and it will allow makeup air into the pump when that level is reached.

[blissville maples]

yes, you will want to add air to cool pump. slowing pump would eventually affect the vane movement and not be the preferred way by me. I did this by taking a 3/4'' steel plug and instead of threading it in, I actually just set it there without turning it. the vacuum held it in place and I could tit it one way or the other to introduce more air. nothing special, quite "rigged" actually but never had a problem ran pump 12 hrs at a time. this was a 78 had major cfms so wasn't an issue for the vac to hold that plug in place, may be different with smaller pump, if so slice the threads with hack saw and thread in one turn, make more "gouge" with saw in thread if need more air. have to be ingenious in this maple syrup industry!

[blissville maples]

a vacuum regulator is just a fifty dollar or more version of what I did for 2 dollars- however a little more perfect or proffesional- results are the same, like I said be ingenious, we're not trying to spend as much money as we can