Which engine for 4101 roller pump?

Discussion in 'Pesticide & Herbicide Application' started by LDH, Nov 21, 2012.

  1. LDH

    LDH LawnSite Bronze Member
    Messages: 1,262

    I know this subject has been beat to death in the past but I'm looking for the best engine/pump combo for my 50 gallon skid. I'm mainly applying pre and post (Triplet and Prodiamine) with Surf King surfactant. I used to own a Lesco Space Saver with a 5.5 Kaw/D403 but with what I'm doing now that's overkill. I've looked at some generic 5.5 hp engines on ebay (Carroll Stream) for $159.99. I'm thinking about a solid 3/4 x 5/8 shaft adapter with 4 set screws to couple this to a a 4101 roller pump mounted on a base plate. I'm kind of stumped on the max 2600 rpm rating on the pump though. This engine is 3600 rpm. Any ideas? Am I going to be forced to go with a belt/pulley drive system, or can I get a smaller hp engine and couple directly to the pump? I would like to stick with the 5.5 hp so that in the future I can go up to a hypro diaphram pump with gear reduction, etc. Advice please.
  2. greendoctor

    greendoctor LawnSite Fanatic
    Messages: 10,122

    I would use the cheap engine for the roller pump and get a Honda or Robin for the D30GRGI when ready for it. When I first started, I used the cheap engine. That way not much lost if my business did not take off. The cheap engine died a couple years later and I replaced it with a 6 HP Robin.
  3. LDH

    LDH LawnSite Bronze Member
    Messages: 1,262

    That's kinda what I was thinking.
  4. greendoctor

    greendoctor LawnSite Fanatic
    Messages: 10,122

    A gear reduced diaphragm pump really does better with a high output 6-6.5 HP engine. A roller pump only needing 2600 RPM could probably get by on 3.5-4. With my current engine, I do have the ability to run a D50 if I wanted to.
  5. LDH

    LDH LawnSite Bronze Member
    Messages: 1,262

    Next question... What horsepower rating will enable me to direct couple to the roller pump without gear reduction pulleys? Will a 4hp or 3.5hp couple without going above the pumps rpm allowance?
  6. greendoctor

    greendoctor LawnSite Fanatic
    Messages: 10,122

    I think you might try a 4 and run the engine at part throttle. Never used a roller pump before so hard to say. The right way to do it is with matching 3 groove pulleys to guarantee that the engine does not over speed the pump.
  7. Ric

    Ric LawnSite Fanatic
    Messages: 11,969


    I won't answer your question, but I will steer you in the right direction.

    Your instruction sheet should have a 800 number for customer support. I strongly advice you to call that number where an expert can answer your questions.

    1st question should be about which pump is best suited for your application? 4101 won't handle fertilizer or any thing corrosive. Cast Iron will rust even with Straight water. You may want to return the 4101 for a 4001XLA which can handle Fertilizer but at 2.5 times the price.

    2nd question should then be about how to mount the pump to the motor. Motor size and operating speed will depend on how you marry the pump to the motor and which direction the pump spins. If you use pulley, then what is the Gear ratio and speeds etc.

    Hypro roller pumps can spin either clock wise or counter clock wise. How ever if you want to change direction the pump must be taken apart and turned around. Direction for turning the pump around come in the box.

    Hypro Roller pump are good if you taken into account they are very cheap. They are throw away pumps in my mind because by the time you rebuild them you can buy a new replacement. Roller pumps cost about the same as a total rebuild kit for a D 30 pump. Ric's Ride the 150 gallon ride on Fire Ant sprayer I posted pictures of uses a 25 GPM roller pump that had to be turned around to spin in the correct direct to marry to the motor. It also runs at RPM higher than recommended. Because it doesn't spray anything but insecticide it uses the standard Cast Iron model that will rust. How ever I think it will wear out before it rusts.

    BTW in calibrating my Ride On Fire Ant Sprayer, I found on line a Tachometer that works like a timing light. By placing the special tape on the shaft of the pump it reads the RPM of that shaft as in spins.
  8. LDH

    LDH LawnSite Bronze Member
    Messages: 1,262

    Thanks for the reply. Like I said, I'm mainly just applying pre and post (Triplet and Prodiamine). I use granular fertilizer, so that's not a problem. I miss my Space Saver and D403, but I'm not willing to spend that much on another Hypro diaphram pump again when I really have no use for it. I agree with you on the low cost and "throw away" mentality when it comes to roller pumps. At $1,000+ for the the cost of a new D403 with gear reduction, I could basically replace a $100 roller pump 10 times before spending the same amount of money. Even if I had to replace it twice a year, that's still 5 years of work before matching the cost of a new D403. From a business sense, it's just not logical. Especially when I'm only applying pre and post emergents.
    That being said... not knowing what might come in the future, I would like to buy an engine capable of being coupled with a D403 or D30 with the gear reduction box just in case I devolope a need for that much pump in the future. This rules out the option of an already gear reduced Honda 5.5, because obviously, an already reduced 5.5 Honda will not accept the gear reduction box made for a D30 or D403. So I'm limited to a standard non-reduced engine which brings us to the question at hand.... how to pair it to a roller pump since a roller pump is what I'm going to go with right now. Should I go with a pulley and belt drive marriage, so that in the future if needed I can just remove the pulley, spin the engine around and bolt up a D403? Or... do they make a roller pump that can handle the rpms that a 5.5 puts out? If so... I will go with a direct 4 set screw coupler. This is my question.
  9. steve's total lawn care

    steve's total lawn care LawnSite Member
    Messages: 64

    LDH i have a honda 5.5 hp engine with a 4 roller pump connected directly to it no gear box no belts pulleys this pump can handle it directly connected to it just run your throttle little less than half way i have pics of my sprayer on my page if you want to see how its hooked up.

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