150 evinrude outboard vaccum switch

[weaver001]

should there be gas getting to or in this switch? and if this switch is shot would it stop the motor from starting right?

[ezeke]

All that the vacuum switch does on most installations is sound a constant warning horn for a fuel obstruction. Newer installations have a warning light.

[weaver001]

thanks. now if i may, have gas going thru fuel pump and flow into carbs and good spark. compression in all cylynders is within specs. motor will only start if i advance the throttle and continue to jog it back and fourth and eventually stops. sometimes it won't start at all. Power packs are new and boat was running great last time out. and checked for spark with a spark tester. any help would be appreciated.

[jonesg]

It helps to put the symptoms in the first post along with important info such as yr and model number.

[metriccrescentwrench]

should there be gas getting to or in this switch? and if this switch is shot would it stop the motor from starting right?

It's certainly possible for a vacuum switch to have a bad diaphragm. If that were to happen it would be like any other leak in a fuel line. Temporarily remove the line to the vacuum switch and plug it with a bolt and see if that makes the problem go away.

[emdsapmgr]

The choke may not be working. Check the fuel primer solenoid to be sure that it is working when the key is turned to "on" and pushed in for cold starting.