boat misfiring and now won't turn over
 

hey guys i have a 2000 supra launch with the indmar assault ....so today me and a few friends were out riding we all took our sets the boat was running awesome.. then we sat around for about thirty minutes and when i got out to take my next set the boat started and then when u tried to put it in gear it would just die.. so i hopped in and just tried to put rev the motor up and it would start and just act like it was trying to run then it would back fire a couple times bog down and die.. did this for a couple times and now she won't even fire up.. it will crank but no firing up.... temp was good oil pressure was good.. just filled up with fuel.. i thought it was vapor lock so tried the water on fuel pump no go... we got pulled in took about 1 hr tried again no go... there are so many possibilities with EFI motor.. i have never had to hook it up to a reader and wanted to know where the plug in is so if its a sensor i can change that... but any suggestions would be greatly appreciated i think i need to start at the fuel filter and spark plugs.. a bud said proxy bad gas... I'm lost as u can tell reading this .. please help!!

hey mate, try checking the distrubutor cap for any corrosion on the points, we had a similar issue with ours , so we just cleaned the points up and it was sweet, hope this helps

Agreed. Start with cap, rotor, wires, filters, coil in that order. Sounds like ignition - then fuel delivery. If it has been at least 3-year since cap, rotor, plugs, then replace anyways because they are over due.

fixed.... after replacing the inline fuel filter and putting some gas treatment in didn't work.... started checkin fuses sure enough a 15 amp fuse was out put a new one in and boom fired right up!

Be sure to track down why the fuse was blown. If the fuse was for the fuel pump, the pump may be going out and drawing too much current. Replace before you are stranded.

hmmm good idea.. talked to my mechanic and he said fuses just blow sometimes... im gonna bring out a couple fuses with me on wens and see if it continues to blow i will trace it down... the fuel pump looked pretty beat up though

So was out today boat ran fine then we stopped and wouldn't start again blew 3 15 amp fuses... So we were stranded .. Luckly a friend had a fuse box so we tried 20 amp to get us home blew that... Then we Trent to a 25 amp fuse fired up and ran let run for a sec then gave it some gas and no issue.... What would b causin this? Is runnin this way safe? It ran fine the rest of the day... I just recently put a new105 amp alternator on it a had a stinger 200 amp alternator? I'm lost please give me some insight?

What fuse is it blowing?
Are they labeled?

Sounded like we were assuming that it was the fuse for the fuel pump...
Check the wires running to your fuel pump. If there is a short, that will cause fuses to blow like that. If all the wires are good, then your fuel-pump could be bad. (Or whatever component the fuse is for if it's not the fuel-pump fuse.)

talked to supra dealer he said its more than likely vapor locking... he said since it ran with the 25 amp fuse that it wouldnt burn up the wires or anything with that fuse... he also said that why it is probably burning up fuses is that the fuel pump is trying to work harder when vapor locking is happening and kicking to much voltage which is blowing the fuse... no the fuse is not labeled .... this is only been happening when we are riding around at slow or idle speeds then cut the boat off.. then we try to start it and it blows fuses... so my solution is no more ethanol! atleast for now.. any other ideas?