Max amperage output on Briggs 25hp question.

[bkeller500]

I need to replace the pump on my Fimco 25 gallon tow sprayer. I currently have a 3 GPM pump that pulls about 10 amps. I am wondering if I can use a 5 gpm pump but the amps use is 17 amps.
I have a 2021 simplicity ZT with a Briggs 25HP commercial/turf motor 44n777-0005-G1. Will the additional amperage draw be a problem? How would I determine the max amp accessory I could power from this Briggs motor.

 

[Rivets]

It will depend on the size of charging system you have on your engine. This manual will probably help you more than I can on this forum. You’ll have to do some math and an understanding how electrical systems work. https://www.briggsandstratton.com/c...a/en_us/Files/FAQs/alternator_replacement.pdf

 

[StarTech]

Please verify engine model number as Briggs is not showing anything under the 44N777-0005-G1.

Meanwhile here some info that might help.

 

[bkeller500]

Please verify engine model number as Briggs is not showing anything under the 44N777-0005-G1.

Meanwhile here some info that might help.
View attachment 60813

I double checked the Briggs part number ( my paperwork was wrong). the motor tag is 44T9770005G1. I took a look at the DC regulator and spotted 2-yellow and 1-Red wire. Guessing it's a 16 amp system ( base on your attachment) .
What would happen if I hooked it to a 17 amp pump occasionally and ran the pump for 15 minutes to spay the lawn? Thanks for your assistance and opinions.

 

[StarTech]

I read carefully what I posted it can be either 10 or 16 depending the flywheel magnets used. Now of course it appears that some one has already modified the engine as it came a tri circuit alternator with the following specs per the model and type number given.

 

[bertsmobile1]

The alternators are not designed to run at full power for extended periods.
Drawing 17A will slowly flatten the battery
It should not be a problem for relatively short periods if the only thing you are running is the sprayer
Adding another 3 amps by spraying while you are mowing is really going to strain the system
I have a commercial customer right now with a dead alternator who just swaps batteries daily while we are waiting for B & S to supply a replacement ( none in stock ) .
When you have finished spraying pop the battery on a charger overnight as leaving a battery partially charged will shorten the battery life .
You can upgrade your alternator to a 20 A very easily
All B & S stators have the same mounting centres so are inter changable .
Take the flywheel off & measure the size of the magnets as per the details in the book Rivets provided the link to

 

[bertsmobile1]

The alternators are not designed to run at full power for extended periods.
Drawing 17A will slowly flatten the battery
It should not be a problem for relatively short periods if the only thing you are running is the sprayer
Adding another 3 amps by spraying while you are mowing is really going to strain the system
I have a commercial customer right now with a dead alternator who just swaps batteries daily while we are waiting for B & S to supply a replacement ( none in stock ) .
When you have finished spraying pop the battery on a charger overnight as leaving a battery partially charged will shorten the battery life .
You can upgrade your alternator to a 20 A very easily
All B & S stators have the same mounting centres so are inter changable .
Take the flywheel off & measure the size of the magnets as per the details in the book Rivets provided the link to

 

[bkeller500]

Thank you both for your replies. My Briggs motor is NEW ( purchased new mower last August so I doubt it's been modified) From the reply's it's clear I'm wishful thinking that I can run a 17 amp pump and not risk damage to the Briggs electrical system. I'm over my head here so maybe a safer option is to just purchase a lower output pump that requires less amps, or purchase a second battery and run the 17amp pump off the spare battery and recharge the battery after each use. I appreciate your feedback and wisdom and willingness to share. Regards.

 

[StarTech]

With proper management a smaller pump on the sprayer can do just as well. Things like a slight stronger chemical mix, slower travel speed, and a narrower spray broadcast pattern all can offset the limitations of the smaller pump.

When I was broadcast spraying with my rider when out with plain water figures my spray rate per acre and mixed accordingly the tank volume for this rate that way I didn't under or over spray the lawn. Spraying the fruit trees was a different ball game so again I had to adjust to what was I spraying at the time. Just common sense things.

 

[bertsmobile1]

You can simply buy a bigger battery and run it as a total loss system
call your 17A draw 20A to give you some wiggle room If you actually run the sprayer for a full hour then a 20 Ah battery should get you done before it goes flat
Then pop it on the charger when you are done
Spiral cell batteries give you the best current draw of all lead acid batteries and from memory the Optimas I use are 75Ah
As you only have a 25 gallon tank pumping at 5 gallons / minute is only 5 minutes of spraying at full pressure so a spare battery should be more than enough
I have a dedicated sprayer mower with a PTO driven pump so have never needed an electric pump.
However I have fitted a couple of 10 to 20 gallon pumps to customers ZTR's so they can weed spray while they are mowing .