Starting problem

[stefangunter]

I have a 96 Mercruiser Sport Jet 120xr, with just 103 hours, which all of a sudden is having problems starting and remain running. It ran perfect last week but the last time I took it out it had trouble starting. Once it did start it would stall when any throttle was given to it. After a couple of tries with slowly apppling the trrottle it would work fine and accerate with ease. Then when the motor is turned off it does the same thing again. After about the fifth time of this it would refuse to start for about 20 minutes. So I sprayed a little starting fluid in the intake (I know this is a no, no but just wanted to see if it would fire) and it ran great until the fluid was burned out. I figure this would be the fuel pump but would appreciate a second oppinion before I start taking it apart. Also it has had a problem with the starter over-heating when the boat ignition is left in the on position for extended time and the boat is not running. Not sure if the two can be related or not but the starter turns fine as long as I don't leave the ignition on. I really would appreciate your knowledgable advice.

 

[rabidfish]

Re: Starting problem

sure sounds like you got a fuel issue. before you try to fix anything, check the fuel itself. make sure it is clean, clear & has no water. <br /><br />Also, the starter shouldn't be overheating from the key on position. Only if it is cranking... for this, you'd better see a real technician. The sport jets are nasty little things when the electrical system catches the boat on fire...

 

[rodbolt]

Re: Starting problem

hello<br /> remove and clean the carbs, a gasket set should be all you need. put a diaphram kit in the fuel pump. on the starter, check for any wires that may have been connected to the stater side of the starter solinoid. there should only be the starter wire on that post. if only one wire is seen then use an ohmeter and test for voltage on the starter wire terminal with the key on , should have 0 volts. if you have a voltage check the solinoid carefully. also check all your engine block grounds. while the carbs are off inspect the reeds. we had a lot of breakage problems with them. do not run a sportjet on the trailer unless you use the flusher that screws on the hose from the pump assy, the standard plastic flusher mounted on the bracket is not suffecient and leads to ehaust plate/gasket blowouts.

 

[stefangunter]

Re: Starting problem

Excellent advice I will try that and see where I get. Thank you