1975 50HP evinrude, starts but has real high idel then sounds like back fire then shuts down any suggestions?

Question

1975 50HP evinrude, starts but has real high idel then sounds like back fire then shuts down any suggestions?

Answer 1

carbs might need to be rebuilt also check your fuel pump

Answer 2

Sounds like a few things.  Seems like it's running lean by what you're saying, then running out of fuel.  You could have an air leak at your intake manifold, if you have weak spark, you could get backfires, pull your plugs and see if they are fouled, replace and gap correctly.  Check your choke operation, probably needs a carb clean as well, and idle speed adjustment.  Make sure you have good supply from your fuel pump, and there's no restrictions.  Pull the inlet line from carb and suck on it to see if the needle is holding.  If you can suck air, hopefully no fuel, then you need a new float needle and or seat, if so equipped on that particular motor.

Answer 3

Sounds like you need to clean and rebuild carb.

Answer 4

Clogged fuel bowl on Carburetor,broken Choke,Broken needle valve on fuel flow.