DIY: Rebuild a Surge Pulsator

(It’s EASY, really!!)

My first foray into Surge milkers came by chance, when Jay and I attended Whatcom County’s yearly farm auction. I had my eye on some milk cans and old bottles and crates, looking to set up my own equipment/dairy. As we were looking around, Jay introduced me to a neighbor and we explained to him why we were at the auction. He said, “I’ve got some old buckets and things, haven’t been used in 14 years, but if you think they’d be helpful I’ll bring them over to your farm.” Not knowing what he really meant, I said, “Sure, that’s very nice of you.”

About a week later, a tractor drives into the farm and Jay saw the bucket of his tractor piled up with equipment. It was our neighbor coming over with the equipment. They unloaded everything into the garage; the neighbor said basically “good luck” and was very happy that someone might be able to use the equipment. When I arrived, what I saw was an original Surge milk pump, 3 Surge belly milkers, a Farm Master milking machine, a Surcingle, and a stainless steel strainer. We jumped into the truck and headed over to DariTech to see if Bryan could help us out. When the average dairy farm in Washington state averages 400 or more milking cows, I doubt he had much experience with people wanting to milk by belly milkers. He tested them out and said that two worked, two didn’t. One was an old “Farm Master” and I never tried to get it working. The other unit, though, I was not ready to give up on. So, I found Hamby Dairy Supply and called up the nice family business in Wisconsin and they helped me get everything I needed. When I got the supplies, I was able to rebuild all my pulsators and had three fully functioning machines. Since then, I have found some more machines at auction to fix up and I’ve never been disappointed. Some people think they need two machines. It’s nice, but not necessary.

First, you should purchase a “rebuild kit” which costs $10-12 and includes:

• 2 leather strips
• 4 leather disks
• 4 tin disk “expanders”
• 1 leather ring (some versions do not include this, so save your old one!)
• 1 small “O” ring (For C style lid only)
• rubber cap for the check valve

Hamby Dairy Supply has a great diagram of where all the parts of a pulsator should be placed. They are the source I recommend for purchasing Surge equipment: hambydairysupply.com/xcart/manuals/surge%20pulsator.pdf

You can attempt to clean your old pulsator and rebuild using its own parts – I have successful done this. But, I do recommend at least keeping a spare kit around just in case something breaks, goes missing during cleaning, etc. The kit includes only the parts that can wear out and deteriorate over time. 

 

Check Valve Tip: If you have a check valve and the rubber is getting old, you probably have the old style. You can tell this way: OLD = you can grab the rubber and unscrew it and there is a screw attached to the rubber part. NEW = The rubber pops on and off, no screw. The TIP is, they say you have to buy a new check valve if your old style wears out because they don’t sell the screw top kind any more BUT if you scrape/cut off the old rubber, you can slip the new rubber over the top and it works just fine!

Optional purchases: The only other wearable part that comes on a Surge machine is the gasket (goes underneath the lid, suction from the milk pump seals the lid to the tank.) Inspect yours. If they are at all dried, cracked, or worn, I would suggest buying a new one. A cheap version of the gasket is only about $5 and a name brand one (they’re about 50% thicker) is $15.

Where to buy the rebuild kit:

• Each kit SHOULD come with paperwork showing you how to put all the pieces together and clean the machine:
• Hamby Dairy Supply www.hambydairy.com
• http://www.surgemilker.com/instructions.html
• Parts Department www.partsdeptonline.com
• Portable Milkers www.portablemilkers.com
• Fisher and Thompson/WestfaliaSurge/other dairy supply stores

Helpful Tools:

• Small flathead screwdriver
• Steel Wool
• Sandpaper (very fine grade)
• Gloves
• Rags/paper towels
• Newspaper
• Pipe Cleaner (from craft aisle)
• Q-Tips

Pulsators can be super dirty – and still clean up like a gem!

Instructions:

1. Lay out newspaper on a flat surface, collect all your tools, and get ready to get dirty! (Old pulsators I’ve rebuilt have been known to be caked with dirt, grease, and dead insects.)
2. Start by removing the four screws on the sides of the pulsator. Note: there is a large fifth screw on the bottom of the pulsator, a little smaller than a dime in size. Never try to adjust this screw! (In the picture, the arrow is pointing to the screw you do NOT want to touch.)
3. Pull outward with the sides and they should slide off. They may be stuck, so you might have to wiggle them back and forth until they slide off.
4. Use the small screwdriver to push out and remove the little rod holding on the lid. This can get loose and fall off when the sides are off, so it’s best to just take it off and set it aside while you are working.
5. The two sliders each have two screws on the inside. Remove those screws. Take apart the pieces and you should have an old leather disk, a tin disk, a metal disk, and a screw. Put back together, but with a new leather disk and tin disk. There may be a disk inside the old leather that is a thin tin disk that looks like a sun. I always like to clean and put that disk in the new leather. Reassemble each side.
   

   

   Note in the above photo on the left, there is a leather with a sun-shaped disk inside it (this sun-disk is found in older pulsators but does not come in a rebuild kit…) the other disk in that picture is the solid one that does come with the rebuild kit. With experience, I’ve learned to KEEP the sun-disk in addition to the solid disk. Why? Because the spikes on the sun-disk help keep the leather expanded properly so that air flows through the pulsator accurately. If your pulsator does not have this disk, it’s ok – just do like I’m doing in the picture on the right: flex the leather pieces before you place them back together.

6. On the main base, remove the long leather strips. After cleaning all the outside parts, use a pipe cleaner to push up into each tiny hole to remove any dirt. Some holes go through to the other side, some curve, so just try to clean and tap out any gunk you can get to. You can put it up to the light to see if the holes are opened. Put on the new leather strips.
7. Remove the pin from the main base of the pulsator. Clean the leather disk or replace with a new disk. Put the pin back in.
8. Using the diagrams, reassemble the metal disks and sliders in the appropriate spots.
9. If steel wool was unable to clean the metal sides of the pulsator or the main base, lightly rub them over small-grained sandpaper. A few motions should clean them up.
10. Put one side onto the sliders and click it into place. There are two little pins on the base of the pulsator that must line up. Screw the one side in.
11. Put the lid back on and insert pin.

12. 

    Clean and ready for rebuild

    After the lid is attached, put on the other side and screw in. If you put both sides on before the lid, you won’t be able to get the lid on! (I’ve done that many times…)

13. Close lid of pulsator. There should be a small rubber ring in with the kit. That goes on the lid of the bucket, then the pulsator twists 90 degrees to fit on top. (The C style lid has a round top where the pulsator fits on and DOES NOT take any rubber gasket. It just slides on metal to metal.)

Final touches:

Adjust pin/leather/nut and place slides on alternate sides (one towards left, one towards right). Place a drop of oil on each side of each slide. Place pulsator on machine, place air lines and inflations back onto machine, then plug in to pump, turn on, and adjust as necessary to get correct pulsation.

NOTE on SPEED of PULSATOR: Be sure, before milking time, to plug in the machine and test the pulsator. You will most likely need to adjust the sliders and the needle to get the correct air flow and pulsation rate.

CLICK HERE to view a short video on how fast a pulsator should pulse.

It’s hard to explain in words, but the pulsation should be smooth and one rotation in about “one-one thousand” time. Think of if you were hand milking a cow. Not very fast, right? So be sure not to set your pulsator at lightning speed. Contrary to what some people think (yes, I’ve heard this over and over) a faster pulsation does NOT milk the cow out faster. In fact, it can cause teat end damage and can cause a cow to hold up her milk (stresses her out). Find a pace that works best for you and the cow and try to maintain that speed. Remember, cows like consistency! Also, you can occasionally oil the machine with Surge or sewing machine oil. One drop per hole (open lid and underneath, each slider has a hole in the middle.) means one drop per hole. And maybe once a month or every few months. Do not over oil or your pulsator will get sticky and  you’ll have to take it all apart and wipe off each part and dry the leathers in the oven to remove some oil!

For more pictures, check out: https://spiritedrose.wordpress.com/jersey-cattle/how-to-produce-quality-milk/machine-milking/

http://www.dallasdomedairy.com/milkingequipment.php

Troubleshooting:

Question from a reader: (condensed version) “I rebuilt my pulsator. I hooked up my surge milker and the first day I got great suction but no pulsation. Do you have any other tips?  I am frustrated because it should work.“

My response:

Yes, that happens quite often. A common cause is if some cotton fuzz gets stuck somewhere from cleaning (like, if you used a q tip or a pipe cleaner…) Spray all the ports with compressed air and see if anything flies out.

Another common cause is that the new leathers are too dry, so you don’t get any suction. Did you oil the leathers when you put them in?

When I say “adjust the sliders” I just mean that when the whole machine is together, you can move the sliding movement (the piece that has a leather on either side) back and forth. Does it move freely, or snugly but easily, or not move easily? You want suction, so you want it to be snug and have a swish sound when you move it back and forth fast. Sometimes, the replacement leathers are a bit narrow and I’ve had success actually flipping them backwards so the “spring” out more once in place inside the pulsator. Also, if you over-oiled the leathers, they will be “gummy” and stick instead of sliding. (To remedy, place leathers on a paper towel for a few minutes in a warm oven.)

Yes, the needle is between the air hose ports. The needle adjusts how much air comes through the pulsator. You should start with it screwed outward (counter clockwise) and somewhat loose, then the pulsator will likely be running too fast and you adjust the leather/nut/& needle inward to get the proper pulsation rate.

Also, I’m not sure which style pulsator you have, but check the “disks” that sit on the pulsator under the leather holding sliders. A common mistake is to put those in flip-flopped, so make sure the bottom side matches the pulsator block base. I have pictures of that on my website, Hamby does too.

Resource:

Does your pulsation system need a check-up?