flojet pump blowing fuses after hours of use?

[racebum]

had an odd one develop. have the standard flojet 4325-143 pump and pressure tank kit on the freshwater system. anyone ever see or hear of a motor failing in this way? it blew a fuse last month. checked wires, replaced. ran about 30 hours of carpet cleaning, popped another fuse. going to wire it direct and bypass the TM wiring just to test {again} but have never ran into this before. usually the pump motors die or you just get a bad pressure switch

 

[Jim Davisson]

You should be cycling less and have less heat on the motor and wiring with a bladder tank on the output side. Having said that I would look into a heat on the wiring feeding the pump, sketchy connection, bad ground, worn wire insulation somewhere, etc...

We found wiring to the ignition switch works well, because the pump was always cut off when the TM was off and could never be left on all night, but could be accessed with the key in accessory position between off and start. Of course on its own fuse.

 

[racebum]

spent the past hour tracing and found exactly that. a smashed wire with only a couple strands on the 12v side making contact that ran to the pump. appeared to be creating resistance {or touching ground on vibrations} and thus the hot slow to blow but melted to a minor degree fuses. very easy to overlook without a bright light and running your fingers down the wires to trace.

no idea how that happened but re ran new 16ga ofc wire from the fuse box to the pump. the pump even sounds stronger now when doing its job.

 

[Jim Davisson]

Glad you found it!

Testing resistance with a meter will help find bad wires. Ohm out the bad wire and a good one for future reference... That type of cumulative knowledge is indispensable for future troubleshooting. If you are an old racebum I ain't tellin you anything new. Cheers

 

[racebum]

Glad you found it!

Testing resistance with a meter will help find bad wires. Ohm out the bad wire and a good one for future reference... That type of cumulative knowledge is indispensable for future troubleshooting. If you are an old racebum I ain't tellin you anything new. Cheers

you are actually. i did go broke racing when i was younger but i never learned that very obvious test method. makes sense. no idea why i didn't think of it. a bad connection or smashed wire like i had would test higher in ohms than a clean unbroken wire.

good advice ! thank you. that goes in the memory bank

 

[sbsscn]

Sounds like you have a short to ground

 

[sbsscn]

You also could have used a continuity tester,
one lead into the pumps connector the other test lead to ground. You would have gotten a beep.

the ohm meter would be testing for resistance,

Go over kill and swap to a 14 gauge, more current flow and less resistance = cooler wire, I would wrap a nylon wire strap coil the harness/wires to protect.

 

[Luky]

You should be cycling less and have less heat on the motor and wiring with a bladder tank on the output side. Having said that I would look into a heat on the wiring feeding the pump, sketchy connection, bad ground, worn wire insulation somewhere, etc...

We found wiring to the ignition switch works well, because the pump was always cut off when the TM was off and could never be left on all night, but could be accessed with the key in accessory position between off and start. Of course on its own fuse.

I know this is older post @Jim Davisson, but word bladder caught my attention. When I was putting my TM together recently, I've asked installers to put bladder tank in also( I had it for a while, so I thought, I put it to work). I've been using flojet 4.5 Gpm pump for many years and I find it reliable. To my surprise, answer for my request caught me off guard. I was told that nowadays demand pumps are quite sophisticated that they don't call for presurized tank . Unfortunately pump froze in winter time and got damaged, so it was time for a new one. Since I live right by RV place where I'm getting propane, I decided to give a shot and bought in their " house " brand Shurflo pump 3.2 GPM. I was worried that pump won't keep up with tile& grout job, but that wasn't a problem . The problem is that I went trough 2 pumps in 6 months. What happens, pump is working just fine to the point that starts to work intermittently, sometimes with help of the hammer I'm carrying with me. Both pumps developed same symptoms, which I have to address with a manufacturer pretty soon. I put in( my mistake) flojet pump 4.9, which caused tremendous whirlpool in my 7x11x12 holding
( hot box) tank and broke off the arm of the float assembly almost immediately. In retrospective, expansion tank would be providing some help with outrageous pressure. Learned my lesson... So , I'm on my 3rd Shurflo , delivering water for about 4 ' away, 3' vertically trough 1/2" hose and waiting on Flojet 3.5 GPM, hoping that my luck turns for the better. My last Flojet pump last 5 years, without causing any problems. What is going on with Shurflo brand ? Anyone else had a similar experience? I would like to know, please. Am I using wrong pump for carpet cleaning application? ( It is diaphragm 4 chamber pump). I had it wired to engine on/off switch, so it's under low electric current only during the cleaning.

 

[Jim Davisson]

I know this is older post @Jim Davisson, but word bladder caught my attention. When I was putting my TM together recently, I've asked installers to put bladder tank in also( I had it for a while, so I thought, I put it to work). I've been using flojet 4.5 Gpm pump for many years and I find it reliable. To my surprise, answer for my request caught me off guard. I was told that nowadays demand pumps are quite sophisticated that they don't call for presurized tank . Unfortunately pump froze in winter time and got damaged, so it was time for a new one. Since I live right by RV place where I'm getting propane, I decided to give a shot and bought in their " house " brand Shurflo pump 3.2 GPM. I was worried that pump won't keep up with tile& grout job, but that wasn't a problem . The problem is that I went trough 2 pumps in 6 months. What happens, pump is working just fine to the point that starts to work intermittently, sometimes with help of the hammer I'm carrying with me. Both pumps developed same symptoms, which I have to address with a manufacturer pretty soon. I put in( my mistake) flojet pump 4.9, which caused tremendous whirlpool in my 7x11x12 holding
( hot box) tank and broke off the arm of the float assembly almost immediately. In retrospective, expansion tank would be providing some help with outrageous pressure. Learned my lesson... So , I'm on my 3rd Shurflo , delivering water for about 4 ' away, 3' vertically trough 1/2" hose and waiting on Flojet 3.5 GPM, hoping that my luck turns for the better. My last Flojet pump last 5 years, without causing any problems. What is going on with Shurflo brand ? Anyone else had a similar experience? I would like to know, please. Am I using wrong pump for carpet cleaning application? ( It is diaphragm 4 chamber pump). I had it wired to engine on/off switch, so it's under low electric current only during the cleaning.

Since you have it wired to the key, when in accessory mode does the pump cycle up and stop in a reasonable amount of time, or does it continue as if building pressure but never cut off? Float arm weeping?

Under use most diaphragm pumps have a 145° cut out switch, if ambient temperature around the pump sustains above that level they become intermittent... Is heat a factor where the new pump lives vs old reliable? Would a fan solve the issue?

Bladder tanks on the outbound side take a little bit of stress off a pump on constant demand. If the pump is unobstructed on the inbound side and reaches pressure right (float tank valve is working right and doesn't weep), consider adding 20' of coiled hose between the pump and the float tank. This pressurized buffer and small amount of added volume between the two very high demand devices could solve your problem.

Consider it and observe what you can see and hear with the TM off.

 

[Jim Davisson]

I did the math on your float tank and should be 4 gallons total and 3.25 guessing full under use. Can flow be directed to the bottom/side for any incoming water so it doesn't look like the front lawn at the hall of Justice in there?

 

[Luky]

Since you have it wired to the key, when in accessory mode does the pump cycle up and stop in a reasonable amount of time, or does it continue as if building pressure but never cut off? Float arm weeping?

Under use most diaphragm pumps have a 145° cut out switch, if ambient temperature around the pump sustains above that level they become intermittent... Is heat a factor where the new pump lives vs old reliable? Would a fan solve the issue?

Bladder tanks on the outbound side take a little bit of stress off a pump on constant demand. If the pump is unobstructed on the inbound side and reaches pressure right (float tank valve is working right and doesn't weep), consider adding 20' of coiled hose between the pump and the float tank. This pressurized buffer and small amount of added volume between the two very high demand devices could solve your problem.

Consider it and observe what you can see and hear with the TM off.

I was hoping that you would read it and not having any questions, haha. Boy, was I wrong , again.
When I meant intermittent, that's before pump dies completely . I would disregard heat factor, since pump will act up in the beginning of the job. You got me on coiled hose, but I would feel bad for a pump after artificially creating way of obstruction . Laws of physics dictate that temperature close to a floor should be the coolest. When situation permits all the doors are open and I felt more heat in the van while operating genset and Escape. These puppies( 230 V motors can get hot) One motor caught on fire in winter time....
Float is not weeping, Ive checked o rings, ( I lightly lubricate them to keep them in good condition, similar to a procedure with a bullet on pressure regulator.)
When I turned that 4.9 gpm pump, tank float started to rattle immensely. Part of the problem might be size of holding tank, I believe that in bigger , wider pool like environment, float would quiet down faster. I had same setup on Escape ( difference was in size of the hose 5/8" instead of 1/2". ( that might be culprit) Same pump was filling 12 gal fresh water tank instead og 1 1/4 gal. holding tank I have right now. No expension tank( pressurized- note for newbies) was used either. Everything you said @ Jim Davisson makes sense, but my gut is telling me that this is not the case. I'm getting new Flojet pump on Monday, so I'll keep you posted with its performance .
Thanks for taking the time.
P.S. Tank float got water in from beginning of time( only 6 months old), I've replaced it with old one( 8 years old, visibly no rust, sound float and better seal on both sides of holding tank.