'81 merc 200 black max hard starting

[JerseyJim]

I have a problem starting my big merc when its been sitting a while. I recently had the fuel pump rebuilt (diaphragm had a hole in it), changed out the fuel line and the bulb, and had the intake manifold gasket replaced (was shot and leaking).<br /><br />The motor has always been 'cold blooded', but has recently gotten worse and much harder to start. I suspect that the fuel bulb has air in it from when we replaced it. When pumping the bulb - it never gets rock hard anymore.<br /><br />When starting the engine, the engine will 'pop', and then stall, whether choked or not. The onloy way I have found to start it is to give the ball like 7-8 squeezes - but the ball never gets hard! Once the motor starts - it will run forever and never quit. I ran compression numbers on the engine not too long ago, and all of the cylinders were 110psi or more. The engine has fresh plugs and clean fuel.

 

[The Marine Doctor]

Re: '81 merc 200 black max hard starting

It sounds like its time to take the carbs off and rebuild them.<br /><br />While you are at it...check to see if the primer is working properly. Remove one of the out lines from the primer and see if fuel comes out of it, when the choke is activated.<br /><br />If the bulb does not get hard..and you have to squeeze the bulb up 7-8 times...you probebly have a fuel leak somewhere..perhaps the needle and seat.<br /><br />TMD