Mercruiser V-8 hard to start

[Bill kubiak]

When I go to start the motor it will crrank and fire and quit. it will do this 6 or 7 times befor eit will settle down and run, Then it purrs.<br /><br />If I shut it off and go to restart it does the same thing all over again.<br /><br />The choke is closed, the accelerator pump is squirting fuel, new plugs, all new filters, new oil change, <br /><br />What can be the problem, this engine should start just like a car

 

[rattana]

Re: Mercruiser V-8 hard to start

What color is the spark? It sounds like it could be electrical. Put a good plug on the spark plug lead and crank it over. Make sure you have a good ground to the plug. Let us know what color it is.

 

[snapperbait]

Re: Mercruiser V-8 hard to start

Run a jumper wire from the positive terminal on the coil to the positive terminal on the battery, then fire the engine.. <br /><br /> If she starts and runs normally, then you have a problem somewhere between the ignition switch and the coil, like a bad ballast resistor, bad connection, ect...

 

[Bill kubiak]

Re: Mercruiser V-8 hard to start

The spark color is a yellow/blue

 

[rattana]

Re: Mercruiser V-8 hard to start

Without actually seeing the spark it seems a little weak and could be causing your starting troubles. Snapperbait's idea is a very good way to check the ignition circuit going to the coil. Did you try this? <br /><br />If you have a voltmeter you can measure the voltage to the (+) positive side of the coil. Connect the positive lead of the meter to the positive wire on the coil and put the negative lead on the engine block for a good ground. You need a helper to do this test. When cranking the motor, you should have 12 volts DC going to the positive side of the coil. When the key is is the run position it should be about 9 volts DC +\- 1 volt. The voltage drop is caused by the ballast resistor or resistive wire in the igniton circuit. The reduced voltage to the coil during run is to reduce the stress on the coil and give it a longer life. Too high a voltage during run will shorten the life of the coil dramatically.<br />If the voltage is too low during cranking then you may have found your problem. We can do some more checks to chase down where you lost the 12 volt DC signal. If the voltages all are within range then I would replace the coil.

 

[denniz]

Re: Mercruiser V-8 hard to start