Need help with my vacuum pump

[spud]

I have a 10 hp Kinney two stage pump. It is a liquid ring pump with a oil reclaimer. My pump lost it's prime yesterday three times resulting in a loss of vacuum. I would wait 15 minutes and then turn the pump back on and all was fine and went right back up to 29 inches. The pump runs 29 inches and then 24 feet away at the releaser it is 28.5 inches. I talked to the CDL service man and he said to check the hoses from the reclaimer to the radiator and the hose going from the radiator to the pump. Both hoses were fine and not plugged. Then I checked the radiator itself and blew air through it. Everything seemed fine there. The pump looses it's prime but there is still oil in the pump. I was told there is a seal in the pump that might be the problem. The seal may not be allowing oil to pass through from the reclaimer but I don't think thats the problem. The pump is full of oil when it looses it's prime. Tonight when I shut the pump down I let it sit for 30 minutes and then opened the drain at the bottom of the reclaimer to see if there was water/moisture and I did drain about one pint to a quart of water. The pump was running since yesterday morning except for it's brief stops because of the loss of prime. Is it possible that the pump looses it's prime due to a pint/quart of moisture that built up over the last 30+ hours? The service man said a half inch vacuum difference between pump and releaser is nothing to worry about. With such a tight system I'm not sure how I am getting that much moisture in such a short amount of time. Last year the pump would run for weeks without any problem. So what I'm wondering is this. Is the pump loosing it's prime due to a small amount of moisture or is it something else like the seal? Until I figure this out I have to babysit the pump all the time. I hate babysitting. Anyone have any thoughts? Thanks in advance.

Spud

[wdchuck]

I had similar issues with a smaller pump last year- problem was the rotor. I wont elaborate.....I did discover a lot along the way though.....Is there a flow limiter between the reclaimer and the pump? Mine was a rubber disc with 3 small holes. The holes could've gotten plugged, no oil. Good luck!

[spud]

I had similar issues with a smaller pump last year- problem was the rotor. I wont elaborate.....I did discover a lot along the way though.....Is there a flow limiter between the reclaimer and the pump? Mine was a rubber disc with 3 small holes. The holes could've gotten plugged, no oil. Good luck!

I'm not sure yet about the pump having any flow limiter. I took the radiator out and flushed it out with air but that did not help. What little we could see inside the radiator was very clean. I ran diesel fuel through the pump last night just in case the radiator is partially plugged. The pump seems to be starving for oil and is running a little hot. I had a service guy come yesterday but he did not have his CFM gauge. What happens is after the sap dumps out of my manual releaser the vacuum drops to about 15 at the moisture trap. It then goes right back to 29 inches. The pump appears to be lacking enough CFMs to make up for lost CFMs during the dump. Thats when I loose my prime on the pump. Sometimes the pump will only run for 30 minutes before loosing it's prime. Other times it could be 10 hours. When it does I just shut the motor off for 10 minutes and then restart the pump and it goes right back to 29 inches at the moisture trap. I'm going to drain the diesel this morning and put fresh oil back in the pump. Once up to 29 inches I will manually dump the releaser to see if it looses it's prime. The service guy said it's either the radiator or the pump itself. I'm hoping it's the radiator just plugged.

Spud

[wdchuck]

Your symptoms are just about identical to mine. It turns my vac pump had problems with the rotor. Previously, a service tech had replaced the shaft seal, totally bungled the tolerances which caused some surfaces of the rotor to get ground off. The metal filings collected inside the ports of the rotor partially blocking the flow of oil and air. Replaced the rotor and the pump maxed out where it should.

[spud]

Where is the rotor located? There is an oil line going from the radiator to the pump. That oil line has a facet style valve on it. Just past that there is a brass T where a small copper pipe goes up to the pump. The oil line goes into the bottom of the pump.

Spud

[wdchuck]

Rotor I'm referring to is the main rotor in a liquid ring pump.

[Brian]

The kinney pump is way diffrent than the Osr. Osr are single stage and the kinneys are two stage pumps.

[Brian]

Try flushing it out with diesel fuel. let it run for a few minutes drain and put in new oil. The water and oil may have put slim in the pump so the oil won't circulate.This might clean the crap out.

[spud]

I ran diesel fuel through the pump for over an hour. I then took the reclaimer apart and cleaned out the oil tank. Either the diesel really cleaned things up or it was always clean. There was some junk at the bottom of the tank. The port where the oil line hooks to the reclaimer and then goes to the radiator is only 1-2 inches from the bottom of the tank. I moved that line up about 5 inches to another port hole that had a plug in it. Something tells me it should have been there all along. I put in new oil and tomorrow we will see if it keeps it's prime even when the releaser dumps. I see Lapierre sells a CFM gauge for $200. I may buy one tomorrow. Thanks for the help guys.

Spud

[Brian]

I would leave the oil line in the lower reclaimer hole. 1 the colder oil will drop to the bottom and 2 there will be less turblence in the bottom to get air in the system to cause air lock or mess with oil flow.

[BAP]

Spud, you mentioned checking hoses in your first post. Any possibility they are collapsing when running? Also, I have seen suction and return line on equipment that deteriorates internally causing it to collapse inside but you can’t see it externally.

[spud]

I was told to change the lines and I am in hopes of getting new ones today. There is no sign of the hoses collapsing but the inner part of the hoses could be breaking up. The hoses are 7 years old.

Brian- The upper hole I was talking about is only about 6 inches higher. There will still be about 12 inches of oil above it. The thought was if crap started collecting in the bottom it would have to build up to the 7-8 inch mark before going through the radiator. Also it would allow more moisture to sit at the bottom in between run times. Right now when i start the pump I always drain a little water out. It might only collect half a cup or less in 24 hours but if the pump stays running for 10 days straight then the water starts going through the pump and it will loose it's prime. 7-8 inches of storage should allow for weeks of run time without problems. Do you still think the hose should be in the lower hole?

Spud

[Brian]

you should be fine. I have the water cooled kinneys, one is 7.5hp the other is 5hp so I didn't know how tall your reclaimer was. You could use hydrolic hoes for your oil lines.

[Brian]

Spud, How did you make out?

[spud]

Yesterday I called CDL and asked for a service guy to come look at my pump. Over the phone we discussed the problem and what I have already done in an effort to fix the problem. They agreed that the radiator must be plugged so they came to the house with a new radiator to install. After looking at it closer he determined that the problem may just be there is not check valve in the oil line between the radiator and pump. Every time the releaser dumps the gauge on the moisture trap goes to 15 inches and then right back to 29 inches. What we think must be the problem is during the dump oil is forced out of the pump causing the pump to loose it's prime. I'm heading to the store at 7:00 to pick up a swing style check valve to put in the oil line. This will prevent the oil from leaving the pump when the releaser dumps. I hope this quick fix is the problem. If I had an electric releaser this never would have happened.

Spud

[Brian]

That makes sense. good luck!!

[spud]

Just installed a check valve in the oil line right off the pump. Still loosing prime after about three or four dumps. CDL on their way. Sap is running.

Spud

[GeneralStark]

Sap is running.

Spud

Yes it is so I hope you get that figured out.

[spud]

Pump has been running for 16 hours without any problems. The CDL service guys and I are scratching our heads still trying to figure out the problem. CDL has been very helpful to me and I thank them for that. I'm going to just take it day by day and hope for a great season. Thanks to the Traders also for your comments and help.

Spud

[GeneralStark]

Hopefully it will run through April! I think sometimes equipment just needs a little attention...

[BAP]

Spud, any possibility it is a motor problem in that the motor isn’t coming up to speed properly? Just thinking outside of the box and sometimes you can get so focused on a problem that you don’t see the whole picture.

[spud]

Spud, any possibility it is a motor problem in that the motor isn’t coming up to speed properly? Just thinking outside of the box and sometimes you can get so focused on a problem that you don’t see the whole picture.

I guess anything is possible. The motor does not die down at all during the dumping of sap. When the releaser dumps and the bottom trap slams shut the vacuum at the moisture trap drops to 15 inches and then immediately goes back to 29 inches. The gauge at the releaser stays at 28.5 during the whole dump. It has done this for 6 years. The pump has been running for 19 hours without any problems. Fingers crossed.

Spud

[spud]

Pump lost its prime twice yesterday but I was able to get it going real fast. While it was down for five minutes I did drain about a cup of moisture out of the reclaimer. This year I bought 8 pails of pump oil because it was on sale for $50. The oil is sp22 but I noticed some of my older oil pails were sp32. The CDL book says the sp22 is for reclaimers which I have. Is it possible I should be using sp32 though? Could the sp22 be causing the pump to loose it's prime?

Spud