99 175 EFI won't rev

[gnfshng]

Ok guys need a little help here. Launched boat, 2000 Triton TR19 / 1999 175 EFI. Cold frosty morning. Boat got covered with condensation on the way to the ramp which subsequently turned to frost/ice when predawn temps dropped into 20’s. Launched boat, cranked the Mercury and it wouldn’t rev – strange. Then it died, cranked it again and let it idle for a few minutes, hit accelerator and it revved up, so let it sit and idle for a few minutes to warm up. Suddenly everything goes dark and motor dies, main boat fuse has blown. Restart motor, again it won’t rev or idle very long. Troll over to bank so I can work on electrical out of the way. Replace 20 amp main fuse with 30 amp (stupid I know but that’s all I have in the boat). Electronics come up, motor starts up and runs. Everything works as designed all day. Cannot figure out why that fuse blew. Is the main fuse and the motor problem related? All I can figure is I got enough condensation on something to cause a short. Does power for the EFI or fuel pump go through the main boat fuse? Need some guidance here other than put a 20 amp fuse back in.

 

[DHPMARINE]

Re: 99 175 EFI won't rev

WOW Lot's can do this,but first thing is to check battery connections clean and TIGHT on BOTH end.<br /><br />DHP <br /><br />wing nuts should ever have been invented for boat batteries.Thank the lords for pliers.

 

[gnfshng]

Re: 99 175 EFI won't rev

Thanks, I checked and retightened all of my connections while I had my head stuck down there changing the fuse. Kind of ruled that one out though due to being able to pass enough amperage to turn the starter with no problem. Of course, with all of the different connections on each post, any one of them could have been corroded.

 

[gap1949]

Re: 99 175 EFI won't rev

Had same problem several years ago. Blew main fuse several times before finding purple wire in control would go to ground when wet. Had spot barely rubbed thru insallation. Would only do it when throttling up when wet. Motor would not run right previous to blowing fuse. Sometimes would run fine and you would not know fuse was blown untill you tried to restart motor. Crazy things happen when they get wet. Not related but got to tell on myself. Worked on customers boat for 3 days, wouldnt get on plane, no power, checked everything 4 or 5 times. Customer came in, feeling kind of dumb, I asked him when this started, he said right after installing a onboard charger. BAMM!!!! leads to main battery were backwards. Changed them, boat ran perfect. He only has a 2 bank charger now. Now I look at anything and everything because it cost me 3 days trying to fix this. I couldnt bring myself to charge him for 3 days labor. $30.00 and he was gone. Sometimes it is the simple things we overlook.

 

[gnfshng]

Re: 99 175 EFI won't rev

Thanks gap1949, That's about what I've got it narrowed down to - I have a wire that either got wet to short or cold enough to shrink enough to kick up the resistence on a bad connection somewhere. Been out a couple of times since when it wasn't quite so cold and haven't had a problem - everything ran great. On your other note - wow,that charger must have a great rectifier in it to not smoke something in the electronics - ouch. We've all traveled that road.