merc sportjet motor problems

[bikertrash27]

I had my boat out last weekend and shortly after I was at full speed the boat just bogged down took it to idle and its fine when i give it throttle it boggs down again I also noticed that it was burning a lot of 2stroke oil as well now it will not stay running if I throttle it but runs fine at idle any suggestions

 

[bikertrash27]

Re: merc sportjet motor problems

ok i got the boat to stay running but now this is what it sounds like it revs for about two seconds and then cuts to idle and runs for two seconds then cuts to idle and so on please help ready to get out the ten pound hammer

 

[Jeff Walkowiak]

Re: merc sportjet motor problems

seems like fuel starvation or water in the fuel tank I had a bad primer ball do that to me once and it drove me crazy finding the issue,, try running on a small outboard fuel tank with good fuel and a different fuel hose to the engine and see if it stops giving you trouble,, if so you know it is in the fuel supply,, also the fuel tank has a check valve built in to the fuel puck up and that could be stuck.

 

[bikertrash27]

Re: merc sportjet motor problems

it was the rev limiter got it running strong without it conected had it out last night ran about 6miles up river and it died no spark had to be towed in by river rescue its the cdi switch box i have spark to it bur not out of it

 

[Jeff Walkowiak]

Re: merc sportjet motor problems

there is a lot of info about the stators and the ignition problems with those engines, it all starts with a bad rectifier , be carefull because replacing the ignition module and not fixing the cause will just blow the new module.

 

[bikertrash27]

Re: merc sportjet motor problems

thanks for the info any idea where to find out more or does anybody have a manual in pdf form they could email me im thinking that i may just buy a whole replacement ingition set but the wiring looks like a birds nest where someone tried peice in a harness my electrician from work said that he would rewire everything for me but he wants a print if i can get it

 

[Jeff Walkowiak]

Re: merc sportjet motor problems

search this site I believe this has been discussed many times