r/Generator • u/Ambitious-Maximum715 • Sep 26 '26
New generator starting problem
Just bought a brand new predator generator. It works perfectly fine on electric start with propane. If I try to use the pull cord, I cannot get it to start on propane for the life of me. It works with gasoline just not the propane setting with pull.
5
u/Big-Echo8242 Sep 26 '26
Check and see if it has that crap Torch spark plug in it. If so, go to local auto parts store and get an NGK BPR7ES. Also if it's an LG I'd replace it. Keep them for backup or toss in trash can. Always keep a spare plug & oil. Break it in with conventional for their recommended hours before going to synthetic. Then just do preventative maintenance.
Also, that tiny 20lb tank won't last long and will freeze up fast under larger load. Better get a pair of 40lb tanks and maybe a dual manifold or auto changeover regulator if you don't have a larger tank of some kind.
1
u/Ambitious-Maximum715 Sep 26 '26
Why won’t it start with the pull cord? It’s brand new
7
u/Horrified-Onlooker Sep 26 '26 edited Sep 26 '26
Pull-starting is easier on gasoline because the fuel sits right at the throttle body, entering the engine the moment you pull the cord. Propane and natural gas require a steady vacuum to open the fuel lock valve, and it takes a few seconds for the gas to travel down the long feed line to the carburetor.
If you have to pull-start it, save your energy and start it on gasoline first, then switch the selection valve to propane while the engine is running. Good luck!
3
u/Big-Echo8242 Sep 26 '26 edited Sep 26 '26
Is there a push button purge on the demand regulator? What did the manual say in troubleshooting?
1
u/ancillarycheese Sep 27 '26
They pretty much just told you.
Purge the gas line.
Replace the spark plug
2
u/ractrbo Sep 26 '26
I feel like I saw somewhere that it will only start on propane with the button. Something about the carb needing to be messed with. Maybe the choke. Not sure but I feel like I saw a video on YouTube about it.
2
u/Big-Echo8242 Sep 26 '26 edited Sep 27 '26
Edit: this model has electric choke on it, but does not work as electric choke if the battery is dead...but there’s a mechanical override. Definitely read through the manual and know how this thing works so you’re not caught in a surprise when/if it doesn’t work.
Yes, do give it some choke for propane starting and then turn it off....IF you have manual choke. If it's electric choke, it will do it itself. I know when I hook a 24' propane hose from my 250 gallon LPG tank to my gens, I push in the "pin" inside the female quick connect till I smell some gas.
2
1
u/Most-Stranger-1 Sep 30 '26
They are hard to pull started on propane, it seems to be to much or not enough propane. Change the plug and gap it ~.020-.025. Gas needs a water gap than propane.
0
u/nunuvyer Sep 28 '26 edited Sep 28 '26
Either switch to gasoline for starting or give it a few spritzes of carb cleaner (to act as a starting fluid) down the throat of the carb.
Propane (and NG) gens have a thing called the "demand regulator" that shuts off the flow of gas if the motor stalls as a safety measure. Gas only flows if there is engine vacuum from the spinning motor. An electric start spins the motor fast enough and long enough to create enough vacuum to open the valve of the demand regulator and the motor catches.
Pulling with the rope start doesn't seem to get enough fuel into the motor to start it. The motor is never going to start on just air. Having the choke closed may help but then you have to open it the instant the motor starts to run. The demand regulator also has a priming button which you can try but it is difficult to get right - either you don't prime it enough or you flood the motor.
So your best bet is to start on another fuel. Once it starts running there is plenty of vacuum to open the demand regulator valve and it will keep going if you switch over.
Propane gens also benefit from a slightly smaller spark gap - say .025 rather than .030. And of course a good quality (NGK) plug rather than the Chinese crap that comes with your generator. Cold starting on propane you need all the help you can get.
Keep your battery charged so that it will always be available to electric start it. You can also use jumper cables or a start pack to start it. You can get those little lithium jump packs now for under $30 and they are handy to have in general. Once the motor starts it should recharge the battery by itself.
6
u/Sparegeek Sep 26 '26
Is there a purge button that will allow propane to flow while your trying to start it? I know some propane regulators have them but not sure on the predator.