Rubber plug over carb jet ?

[picklenjim]

I have a 96' Yamaha 25 hp on my jon boat.Motor would only run with the choke on.I suspected the main jets were clogged so I removed both carbs.After removing the bowls sure enough they were cloged on both carbs.That should take care of my problem but what I was wondering is right next to the main jet is another jet down in a hole.I assume it's the intermadiate jet but they have rubber plugs in the hole covering the jet.Does anyone know why? Would it possibly run better with these plugs removed. I have seen carbs before with the main jet and intermdiate jet set up like this but never with a plug in the hole covering the one jet.

 

[99yam40]

Re: Rubber plug over carb jet ?

If you look closely, there should be a hole between these two jet tubes under the main jet and under the plug.
I believe the reason is for the main jet to limit the amount of fuel through the idle jet during high speed. If you remove the rubber plug it would allow fuel to flow through both at the same time causing an over rich condition.
But this is just my theory on the system.