150 EXEOM 1995- Purple accesory wire to ignition blows fuse

[w2much]

Enlighten me please. Motor will crank and start and run with the purple accessory wire off of the ignition switch . As soon as I put it (the purple wire)back on the ignition switch the fuse inside the cowl will blow. Of course the tach , fuel and amp meters will not work without this wire in place. The trim and tilt will work from the side of the engine but not from the binnacle control.

 

[Chris1956]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

I had that issue on my 1998 Johnny 150HPV6. I found several places on the boat wiring harness, where the wires melted. Sometimes purple would melt into black and short. Look under the dash, and look where the engine harness meets the boat harness.

Keep in mind that the wiring harness' are different between our motors. You should have the big red plug, right?

 

[Silvertip]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Check the +12 volt and ground connections on each of the gauges. It is very common for the connections to loosen. This allows the terminal to rotate on the stud and possibly short to the ground terminal. Or the ground terminal can rotate to short to the +12 terminal. Since the purple wire does not go back to the engine there is likely NOT a problem in the engine harness. If this is a side mount control, then there could be a problem inside the control box. If this is a console mounted ignition switch the issue is very likely with the instrument wiring, or with some device being powered by that wire. Keep in mind if there is something other than instruments fed by the purple wire, it should NOT be. That circuit is intended only for the instruments.

 

[w2much]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Thank you both for your replies, I do appreciate them. Messed around for a while and thought it better to walk away til next weekend, gather some input and attack the issue next weekend. So if the purple wire when connected to the ignition switch blows the fuse immediately the problem is after the switch? Or as Chris mentions the wire may be frayed(burnt or whatever) before the ignition switch, between the red plug and the ignition switch. I will mention that the boat and the binnacle and the gauges are 1996 , the motor is a 1995. There is an adapter harness under the console which appears to be in good shape. Could this have to do with a bad regulater/rectifier?

 

[keefallan]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

If it blows immediately, It has a dead short in it.......Take it to the bank. You need to check all the connections. It is grounded somewhere. You will have trace it out and check everything that's connected to it. In a pinch, you can run another wire from point a to point b if you have to. What I would is this. Find out the first device that is tapped off of this wire(tach etc). Disconnect everything else and connect the wiring. Then you'll know if the fault is in the dash of in the motor/harness to the dash.

Silvertip is correct. The purple wire is intended only for gauges. BUt since it is blowing immediately, you have another problem.

 

[boobie]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

When you do as said above have a box of fuses handy. When you find the one that pops the fuse, that's the culprit.

 

[w2much]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Just to gather some info for my issue at hand.With the ignition off this wire carries no current? This wire should only be powered from the ignition switch (on position)? With a test light, purple wire unhooked from the ignition switch the test light should do what?

 

[seahorse5]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

A short in the regulator - if it is the original style - can blow a fuse as soon as the key is turned to ON, or a pinched wire somewhere in the powerhead.

 

[daselbee]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Purple wire DOES go back to engine. Most likely, the problem is the at the gauges as mentioned above, but could be at the VRO pump connector area, or possibly the old style reg/rectifier. Don't blow a bunch of fuses. Wire a 12v auto light bulb across the fuse contacts. When the short EXISTS, the light will be on bright. When you remove the short, the light will be off. THEN, put a fuse in....saves mucho dinero.

 

[w2much]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

I found that the problem /or the symptom was was the tach. I hope it was the problem and that the issue is resolved. I felt the wires were warm leading to it and happened to have another one to replace the one that was in place. All is well on the driveway as I ran the motor and did multiple restarts to test.Thank you all for your help. Has anyone heard of this problem before. The old tach has the burnt electric smell.

 

[keefallan]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Electrical issues are always "fun" to trace out. Sometimes there's no rhyme or reason. Other times it has a definate path. When something breaks down it just does sometimes and you have to be able to troubleshoot it.

 

[emdsapmgr]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Glad you found the problem. You might want to go an extra step. That purple wire can be used to provide power for a tach-only. Not recommended to attach other electrical parasites to it. (ammeter/fuel gauges) I'd wire any/all other gauges direct (fused) to the battery with the bilge, horn, lights, radio, etc. That engine has a 20 amp engine fuse and could blow if overloaded with other devices. If it blows when out on the lake, the engine won't start-could be a problem.

 

[Chris1956]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

I disagree with last poster. The purple wire is intended to power all gauges and warning systems. These devices take a very small amount of power.

Devices that take more power (Stereos, radios, lights, horns, etc) need to be wired thru a fuse and an accessory switch to the battery.

 

[emdsapmgr]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

The factory service manuals permit up to a 5 amp parasitic load on the 3-wire pigtail from the control box.

 

[out 2 launch]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

The factory service manuals permit up to a 5 amp parasitic load on the 3-wire pigtail from the control box.

Actually the factory service manuals permit nothing. It may list a recommended maximum load value, of which I am unaware of any, which is not to say that there isn’t any, I just haven’t seen it. The allowable factory recommended load, be it parasitic or otherwise, off the engine circuit, is determined by the fuse. If you could would you provide reference to the above quote, I’m always open to new information.

 

[Chris1956]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Gee, standard gauges use a few watts each. 5 Amps is 60 watts, so you could hook up a lot of gauges.

 

[emdsapmgr]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Check out an factory 86 service manual.

 

[out 2 launch]

Re: 150 EXEOM 1995- Purple accesory wire to ignition blows fuse

Got the 150 EO factory service manual here in front of me, section #7 "Electrical System” no mention of parasitic load. Am I in the wrong section? 86? Whats 86 got to do with it? Seloc, are you kidding me?