Burning fuses

treatwater44

Recruit
Joined
Jul 29, 2006
Messages
2
Hi all, I have a '98 150 and I am having some trouble. I was out and lost all power due to some corrosive connections on the battery. I changed out the terminal and still had no power. I pulled the 20a fuse and it was blown. I replaced it and blew it again. Replace once more, now I have power ( tilt steering works and guages work ) but when I attempt to start the motor it blows fuses continiously. HELP !!!!!!! Thanks
 

fireman57

Captain
Joined
Aug 24, 2004
Messages
3,811
Re: Burning fuses

You have a short or open somewhere in your wiring. To see if it is in your iginition switch unplug the big red plug in your wiring harness to your engine and jump to the starter from the battery. Make sure that you are on the trailer and in the water because you will have to choke it to stop the engine. If the fuse doesn't blow you could have a faulty ignition switch. If it blows again then you have a bad wire on your engine somewhere. Clean all the grounds and terminals. Are you sure that you don't have the battery hooked up backwards?
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Burning fuses

Opens don't blow fuses. Shorts and overloads do. Since the problem occurs when you attempt to start the engine, check the back of the ignition switch. The connections on the back can come loose and the terminals will then spin around and make unwanted connections. Check the small wire at the solenoid. If you added anything to the boat lately, ensure you didn't run a screw into the engine harness.
 

treatwater44

Recruit
Joined
Jul 29, 2006
Messages
2
Re: Burning fuses

Silvertip said:
Opens don't blow fuses. Shorts and overloads do. Since the problem occurs when you attempt to start the engine, check the back of the ignition switch. The connections on the back can come loose and the terminals will then spin around and make unwanted connections. Check the small wire at the solenoid. If you added anything to the boat lately, ensure you didn't run a screw into the engine harness.


I checked the back of the ignition switch and everything seems to be fine. Is the small wire to the solenoid red ? I am blowing fuses now without turning it all the way over. I dont mind replacing the solenoid and ignition switch ( piece of mind ) if its not hard to do. I have never done it before and could use some insight on replacing both. Thanks
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Burning fuses

No need to replace either item. But the best technique at this point is to begin disconnecting things one at a time until you locate the circuit giving you the problem. Pull one fuse at a time or disconnect one device at a time. If you are blowing the large fuse, you have a substantial short somewhere.
 
Joined
Jul 29, 2006
Messages
21
Re: Burning fuses

Silvertip said:
Opens don't blow fuses. Shorts and overloads do. Since the problem occurs when you attempt to start the engine, check the back of the ignition switch. The connections on the back can come loose and the terminals will then spin around and make unwanted connections. Check the small wire at the solenoid. If you added anything to the boat lately, ensure you didn't run a screw into the engine harness.
the captain has got it right go with him, lol
 

Dunaruna

Admiral
Joined
May 2, 2003
Messages
6,027
Re: Burning fuses

[colour=blue]There is a simple way to test for a short that GUARANTEES you won't fry anything.

Make one of these from a headlight globe (quartz halogen), wire it up as pictured.

http://img.photobucket.com/albums/v259/Dunaruna/P5250012.jpg

Disconnect the ground battery cable, connect one of the test leads to the battery ground post, connect the other test lead to the disconnected ground cable.

Now do what silvertip has suggested (turn things on/off, wriggle looms, turn the ignition on/off etc etc).

If a short exists, the headlight globe will illuminate. The brighter the illumination, the more severe the short.

Remember, the battery is disconnected, you cannot do any damage testing this way. It is also a good way to determine if a short is minor or major (with a bit of practice). It is also a good way to test when you are alone - ie: you are up at the helm wriggling looms but the headlight globe is down the back of the boat.
 
Joined
Jul 30, 2006
Messages
24
Re: Burning fuses

Had my fuse also damaged. Had a short in the purple wire that comes from the ignition switch, and gives power to the instruments as your trim meter and rev meter.

Had a built in radio wich frame touched this wire everytime hit a big wave. It drove me mad...
 

freddyray21

Commander
Joined
Jun 10, 2006
Messages
2,460
Re: Burning fuses

no need to make a convoluted headlight contraption you can to the same thing with a volt meter If it reads more than 6 or 7 volts you have a short somewhere. A short will usually indicate 12 volts on the meter when you unhook things on at a time when you find the short the voltage will drop. If it is only doing it when you are trying to start you have a short in that circuit or you are drawing too many amps through the starting circuit.
 
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