Briggs & Stratton upgrade to 23 HP - won't fire up

[Dave Raybuck]

Hello we recently upgraded to a 23 HP Briggs from the 18 HP in our Bigfoot. The problem we are having is getting gas to the carb. Gas does get to the carb but something is stopping it from getting to the engine. Is there a hidden shut off valve we are not seeing? We checked plug and got spark. It will start if using starting fluid or if we dump fuel into the carb. We also installed a new wiring harness and everything seems to be correct on that. We can feel the fuel cylanoid click when we turn the key to the on position. Any advice would be appreciated.

[Lantz]

Sounds like your carb is plugged up. Is there gas in the bowl after you try starting it? Theres probably something between the needle valve/seat and where the fuel enters the carb. A good carb cleaning should solve your problems.

[Dave Raybuck]

Thanks Lantz for your response. This is a brand new Briggs and Stratton 23 hp engine. I don't know how it could be plugged up. The manual says there isn't any adjustments on the carb, except idle. I can not find a needle valve on the carb.

Thanks in advance,
Dave Raybuck

[amphibious drew]

Thanks Lantz for your response. This is a brand new Briggs and Stratton 23 hp engine. I don't know how it could be plugged up. The manual says there isn't any adjustments on the carb, except idle. I can not find a needle valve on the carb.

Thanks in advance,
Dave Raybuck

Make sure the selenoid on the carb is getting power during ignition. If its hooked up wrong it will never fire up.

[msafi65]

Check the carb solonid wire for power while cranking some ignition switches drop ACC power when cranking. If not just jump power to wire and try to start. I just had a new Briggs with the float needel
Out of place and stuck shut. The 23 has a different carb but it can happen

[Dave Raybuck]

Thanks, I hooked the solenoid wire to the "ON" side of the ignition switch. Does it have to have power on all of the time, like right off the battery? Or does it have to be powered only during startup?

[PlumCrazy]

Thanks, I hooked the solenoid wire to the "ON" side of the ignition switch. Does it have to have power on all of the time, like right off the battery? Or does it have to be powered only during startup?

The solenoid needs power(12v), when you want the 23 to run.
You want the solenoid power off, when ever the key is turned OFF.
Put the key in the RUN position, not the START position, use a meter to find the 12v lug, hook the solenoid wire to that.

[Daver]

Hi PlumbCrazy - That is what we had it spliced to (the on position wiring from ignition switch) but I think he hooked to the start position switch and it fired up ok this morning. I'm beginning to wonder if there is another wire needed on the harness when upgrading to 23 from 18. We have went over the wiring diagram. My thought was we would want the cylinoid to be powered in the start position to draw the initial fuel charge then when it goes to the on position after it fires up the fuel would self draw from compression suction. Maybe I am wrong...but maybe we want the cylinoid powered in both positions...that's why I'm thinking it may require an extra splice to both on and start positions.

[msafi65]

Has to have 12v in start and run to allow fuel into main jet in carb. Without power it will not run

[ARGOJIM]

If your starter solenoid has 2 posts you can run a wire from the I or empty position and tie it in line to the fuel solenoid, it would work the way that most Fords do supplying power to the ignition circuit while cranking.
Unless your key switch has a spot other than the s terminal that has power while cranking.

[Daver]

Thanks for the replies! I think he ordered a new ignition switch for the 23hp. I think the 18 ignition didn't have the sylonoid wiring. We could probably just splice it in each one but the ignition switch needed replaced anyhow it has a tendoncy to want to stick in the run position even when it appears to be in on.

[srfnson]

Congrats on getting it working...

I'd love to do this upgrade on my Bigfoot...how difficult was it and what additional parts/mods did you have to make?

[wheeler]

As stated above, it could be any one of those problems. But, one thing I would check is take the fuel line off of the engine and turn the engine over to see if any fuel comes out of the gas line after cranking it over for 10 seconds or so. If not, you might consider what I'm going to probably have to do. A mechanic said to put in a electronic fuel pump. I upgraded to a 23 Briggs brand new also and have to hold open the throttle and choke it to get is started.