Fimco sprayer pump replacement

browndog

5 year old buck +
I have the ATV 25 gallon sprayer with boom and I think the pump is on its' way out. It's the original 2.1 gpm pump that came with the sprayer and it's about 10 years old. I'm thinking about replacing the 2.1 gpm pump with the 3.8 gpm pump. I think the bolt holes will line up and was wondering if the 3.8 gallon pump would be alright? Would there be any problems with the boom nozzles with me using the 3.8 pump?
 
A lot of times parts can go bad on these pumps but they are easily replaced the pump should not go out. I just replaced a pressure switch on my 30 gallon sprayer and also there's no need for that big a pump on a 25 gallon sprayer. Mine is a 2.1 and it keeps up fine.
 
What are the symptoms? Maybe we can help.
 
It has a grinding noise when it is running and has a bad leak also when it's running. I haven't taken it apart or off the tank yet.
 
I once broke some pieces on mine when it slid off the ATV rack and slammed the ground. I was able to order replacement parts, I believe directly from Fimco but I'm not sure. Stupid mistake that I thought was going to cost me the price of a new pump ended costing less than $10.
 
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Grinding noises would indicate bearing issues or possibly struggling to build pressure. When you're not spraying will it hold pressure or does the leak cause it to struggle to build pressure? The leak could be responsible. If it were me I would start tearing into it for a learning experience especially since you want to replace anyway.
 
 
Along these same lines......when using my Fimco 25 on Sunday......I had a problem with the pump not turning "on" when using the inline switch that goes to the battery. Was kinda frustrating....as it would work at times....then not. All the electrical connections seemed good....and the in-line switch seemed to work. Could this be a faulty pressure switch? (hope I'm not hijacking here)
 
Grinding noises would indicate bearing issues or possibly struggling to build pressure. When you're not spraying will it hold pressure or does the leak cause it to struggle to build pressure? The leak could be responsible. If it were me I would start tearing into it for a learning experience especially since you want to replace anyway.

The only time it leaks is when I'm spraying with the boom. Of course it runs down the tank and onto the seat and my rear soaks it up. I'll have to tear it apart and see what's going on but I need to get the rest of my plots sprayed. $61 for a new 2.1 or $100 for the 3.8. I looked at a parts diagram like the one above and the pump listed was a 3.8, that's why I was wondering about putting a 3.8 on my sprayer.
 
Along these same lines......when using my Fimco 25 on Sunday......I had a problem with the pump not turning "on" when using the inline switch that goes to the battery. Was kinda frustrating....as it would work at times....then not. All the electrical connections seemed good....and the in-line switch seemed to work. Could this be a faulty pressure switch? (hope I'm not hijacking here)

Foggy, I had a problem with my in-line switch years ago and I took the switch out and hardwired it. My pump has an on/off switch right on the pump itself and that is how I turn it on/off. I see that the new shurflo pumps at Fleet Farm dont have a switch on them anymore.
 
Foggy pressure switch would be only if pressure doesn't build up which would be stuck diaphragm or bad switch but all of the on/off wires have sucked hard wiring or just dealing with them is the solution.
 
Not really sure what you want to gain with a bigger pump. I spray 30 gal tank with 5-6 ft boom on 2.1 and it sprays out hard with no pressure problems. If you buy the same size then you also would have replacement parts if needed. I still believe you can fix the other one.
 
If your system originally came with a 2.1 going to a larger pump isn't going to really help anything. The pump flow is still restricted by the number of nozzles and the size of them. Unless you have plans for further modifications it simply isn't required. If you changed spray tips to allow more flow (along with you using the larger pump) you could then increase your travel speed while spraying. Now I use my sprayer as a water tank as well (watering fruit trees or during controlled burns) so if you do the same more flow means it will empty your tank faster if that is important to you. I also agree with learning something by tearing it apart - if you go with another 2.1 you now potentially have spare parts as well. Best way to keep something from breaking is by having the part already available at least it seems that way. Foggy's issue sounds more like a poor connection or short somewhere to me.
 
The thing with these sprayers that you need to remember is that they don't get used often enough so seals can dry out and parts can stick. Good point above about nozzle tips if I'm spraying for weeds then I want a fine mist which would reduce the need for a bigger pump.
 
If the pressure switch is bad, it can either not make a connection or it will not shut off. If the leak is from the pump, check hose connections (hose clamp), and barb to threaded connections. If there is a inline shutoff from pump to nozzles, close the shutoff and check for leaks. One way to check pressure switch is to put a 1/2" pipe plug in the outlet of the pump, to see if it shuts off. If it leaks from the seals, a replacement pump head is available. If you suspect the bearings are bad (noise) replace pump, with a 2.1 gal one. Do you know what the output of your nozzels are at various pressures? I have a bypass with a 3 way valve so I can adjust the pressure and know what the output of the nozzles are.
 
If you have a problem call customer service and they will walk you though a couple of tests. My pressure switch went out at the end of the season last year when I was getting the sprayer ready for winter. FIMCO sent me an email with directions on how to test the pressure switch which worked well. I replaced the switch and this year it works like it should.

Sometimes I think the heat of sitting in a shed is hard on these pumps.
 
The diaphragm in the switch is usually the culprit before the switch itself goes it either sticks or becomes air locked. I usually would have to remove and reseat diaphragm each use. Only reason I replaced pressure switch on mine was because I broke the plastic housing when tightening screws.
 
If the pressure switch is bad, it can either not make a connection or it will not shut off. If the leak is from the pump, check hose connections (hose clamp), and barb to threaded connections. If there is a inline shutoff from pump to nozzles, close the shutoff and check for leaks. One way to check pressure switch is to put a 1/2" pipe plug in the outlet of the pump, to see if it shuts off. If it leaks from the seals, a replacement pump head is available. If you suspect the bearings are bad (noise) replace pump, with a 2.1 gal one. Do you know what the output of your nozzels are at various pressures? I have a bypass with a 3 way valve so I can adjust the pressure and know what the output of the nozzles are.

I'm quite certain that the leak is coming from the pump itself, it looks like it is on the bottom side of the pump and there is only a 1/2" of clearance between the pump and tank. I believe the head of the pump comes off and it is probably a bad seal. I suspect the bearings are going too. I have one valve that controls the flow/on/off to the boom(7 nozzle boom)which is how I control the pressure to the nozzles. When that valve is off there is no leaks from the pump or any connections...it only leaks when I'm running the boom nozzles. There is one other valve that allows the pump to pump back into the tank and I don't think the pump leaks when I run it like that.
 
Foggy, I had a problem with my in-line switch years ago and I took the switch out and hardwired it. My pump has an on/off switch right on the pump itself and that is how I turn it on/off. I see that the new shurflo pumps at Fleet Farm dont have a switch on them anymore.
Thanks BD. Kinda felt I have a switch or connection issue on an occasional basis. The "occasional" issue makes it hard to troubleshoot.

I do have a switch on my pump too. I gotta believe the problem is with the in-line switch at this point.
 
Foggy it also could be the connection that plugs the switch wire to the pump wire. I would cut those off and direct wire but keep the switch to see if that works. If it still doesn't work then lose the switch but it's much more handy having the on off switch.
 
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