Battery will not hold a charge

https://shoptoolreviews.com/automotive/diagnostic-testing/parasitic-battery-drain/34587/

Is the solenoid staying engauged?

I have a Bushnell Tour V2 that has worked very well for over 8 years and it just started doing the same thing with the frozen screen and 1888 yards. Since I just replaced the battery that I bought at a Pro Shop about 6 months ago I thought the battery was fine. I looked at the battery and did not recognize the brand so I went out and bought a new Copper Top Duracell and BANG it is working again just like new.

Either its a bad new battery or tour altenator isn't charging it. Jumpstart it.

starting up is way to slow
fuel pump pressure down
or EFI system fault , a faulty starter
if that all checks out
the 4 day to flat battery
parasitic draw from alternator ,
starter solenoid or starter motor
or ignition switch

you can buy quick release type battery terminals like used on marine boats

charge the battery up
and disconnect the battery terminals
until you want to drive the car again
when back home undo the battery terminal

You will need to do 3 tests:
1 - you must find out if you have a short in the wiring: disconnect the + cable from the battery and put an ampermeter in there to close the circuit; if a current is detected it means that you have a short and it will drain the battery. To locate the short start disconnecting wires and look at the meter - when you will disconnect the wire that goes to the failed wire or part the current will stop flowing; find the faulty part and fix or replace it.
2 - you must find out if the alternator is charging the battery correctly: start the motor, wait for half an hour then measure the voltage on the battery. If it's below 14.1 volts then the alternator is failing and it will have to be replaced.
3 - you must find out if the battery is in good working order: after the second test has finished shut down the engine and disconnect the battery; wait one hour and measure it -if the voltage on it has dropped to below 11.8 volts then the battery has aged and it's no longer holding the charge so replace it.

check under the battery is there a little pink/red circle

could be a out sinked carb or gum from sitting gas won't last long

I would try a new battery. How old is the battery? Your probably right about the battery not holding a charge.

the battery is no good, the battery charges but it can't hold the charge. This could be because of age or damage.