7 1/2 mculloch keeps dying ???

[Kauaiboy206]

I've got a 7 1/2 mculloch outboard that starts and idles fine but then dies out after a few seconds. I have to constantly press the primer bulb to feed it gas right before it starts to die in able to keep it running? I checked the fuel tank lines and vent, but no idea as to why it keeps dying? It starts up just fine after a few pulls.

 

[GA_Boater]

Pumping the bulb to keep a motor running usually tells you the fuel pump needs rebuilt.

 

[flyingscott]

Couple of things to try first. Where the fuel line connects on that motor is the housing for the fuel screen. Those can get goobered up and not allow fuel through. Another thing to try is opening the low speed screw a little more. If you have to do the fuel pump you have to pull the powerhead off. This is because the diaphragm sits in the bottom of the carb I can guarantee It will be a PIA. I am assuming you have the low profile 7.5

 

[tomhath]

If you decide to rebuild the fuel pump, do yourself a favor and rebuild the carburetor and water pump at the same time. All of those involve pulling the powerhead so you may as well get everything done while you have it off. If you have the Bail-o-matic version you should replace both impellers.

 

[flyingscott]

Power head does not need to be removed for the water pump on that model. Impeller and carb kits are available. Make sure you get the carb kit for the Marvel Schebler carb. The impeller is the same for the main pump and bailer. No need to replace the bailer take the main impeller and put it in for the bailer. You will also need the powerhead base gasket. My advice ONLY pertains to the low profile motor Which I Am Guessing yours is.. Put up a pic.

 

[tomhath]

How do you get the carb off without pulling the powerhead? I sure couldn't see a way.

 

[flyingscott]

How do you get the carb off without pulling the powerhead? I sure couldn't see a way.

Post #3 specifically says you have to pull the powerhead for the carb. Post #4 Says Powerhead needs to be pulled for the water pump. Post #5 specifically says powerhead does not need to be pulled for the waterpump.

 

[tomhath]

Aagh. I misread #5 as fuel pump rather than water pump.