Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndrive

[btodd1]

My boat started and ran for 10 minutes a couple times. I was getting it ready for the water and the horn was not working. I recently purchased this boat and it had sat for two years. I have gone though it. New deck and carpet. First day I got it the engine would not start but did turn over. I had to put a new coil and points. Then it was awesome. So, back to the horn. I pressed it and it sounded like a dying duck. I figured it was a bad ground so I checked and it was a bit loose. I tightened it and I tried the horn and it worked good and loud. I pressed it again and it went dead. I checked the battery and it was fine. The trim and trailor up switches worked fine. But when I turned on the key. I got no power. I wiggled the wires under the dash and it still did not work. I checked connections in the engine compartment. I wiggled some ground wires and it still did not work then, while working on something else, I turned the key and the engine started and ran fine again. OK, so I do some more clean up and rubbing compound on the body. Almost ready to put in the water! OK so i go to start and nothing. So I took a hot wire from the battery and touched it to the power side of the solenoid and it started right up. It ran for 1 minute then shut off. I noticed there was no more gas dripping into the carb. Then I felt the Purple/pink/ or purple/vilot/black wires going to a cylinder on the side of the carb and they are really hot. Then I start disconnecting the fuse block because I'm thinking it could be a short behind the dash. I figure I will re connect one at a time till I see if the carb wires get hot again. Later with the fuse block off, I turn the key and it revolves once and stops. No power to start again. Any help on and easy way to troubleshoot this or what to look for would be appreciated. Thanks!

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

I would check all connections on the big cables to and from the battery & starter for corrosion and tightness. It seems to be happening on several circuits so it could be something thats common to them. You may need to use the schematics to break that down further.

If the wire going to your electric choke is getting hot /Make sure you have the proper fuse per the wiring schematics. The fuse should trip well before the wire gets hot from electriacl current passing through it as part of the design. (For Fire Safety)
Any chance it was engine generated heat from a manifold?? / If not I would also inspect the heating element for possible shorting by bebris or moisture / it may need to be replaced.

 

[nola mike]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

There should be a purple wire connecting your choke to the coil--that's your resistance wire, and should be hot (well, hotter than a normal wire). Check the adults only sticky for troubleshooting your starting system. If a hot wire to the slave starts the boat when the key doesn't, then you'll need to make sure you're getting power to the slave from the ignition...

 

[btodd1]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Thanks guys for the quick reply to my post![/B] I got a new battery today. I cleaned up a lot of the dash wiring. I replaced the old fuse block with a new one. All accessories are working now. I moved the horn ground as it was daisy chained to the fish finder. I'm not a big fan of daisy chaining everything. So the wiring all seems pretty stable now. However, I mentioned the hot chock wires or the purple resister wire from chock to coil. I have new informaion on that now. It get's super "HOT HOT HOT" whant I turn the key on only. Although it does nothing when I try to turn it over. So I'm thinking it's possibly the iginiton switch. What do you guys think? Thanks, Bret :0)

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Glad to see your making proress.

If its a resistive wire the scematic should indicate that & it should get warm but not too hot. A resistive wire will reduce the current flowing through it and will generate some heat in the process. That's something you may want to ask to somone who is more famliar with that ckt

I am not highly familiar with the ckt yor talking about but can give you some detail.

Wires are only able to handle a certain amout of current-- if that is exceeded they get hot. The current is controlled by resistance ad the voltage applied. for example 12 volts / 2 ohms resistance = 6 amps. If the resistance drops near zero the curent will go up exponentially and melt the wire( this is commonly called a short ciircuit). A faulty ignition switch would deliver low or 0 volts to the ckt / or 12 volts if its good so its not likely to be the root cause.

If the heat you are seeing is abnormal;
You may want to measure the current through the wire and alo the resisance of he electric choke with a DVM Meter. A schematic of the wiring would be helpful as well. Post your findings & we will try and help or consult someone with an electronics background.

If the wire does go into meltdown its a fire hazard so its probably a good idea to be careful here. Good luck

 

[nola mike]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Thanks guys for the quick reply to my post![/B] I got a new battery today. I cleaned up a lot of the dash wiring. I replaced the old fuse block with a new one. All accessories are working now. I moved the horn ground as it was daisy chained to the fish finder. I'm not a big fan of daisy chaining everything. So the wiring all seems pretty stable now. However, I mentioned the hot chock wires or the purple resister wire from chock to coil. I have new informaion on that now. It get's super "HOT HOT HOT" whant I turn the key on only. Although it does nothing when I try to turn it over. So I'm thinking it's possibly the iginiton switch. What do you guys think? Thanks, Bret :0)

Have you tried going through the troubleshooting steps from the sticky yet? Again, purple wire should be hotter than a normal wire. Is the other wire coming into the choke also hot? A bad resistor wire shouldn't affect starting--it certainly shouldn't keep your engine from turning over.

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

I took a minute to reread al this & wondering if you can elaborate on the problem statement(s)

--Wire getting hot -what exactly does that wire go to and what does the ckt do /- Any possiblility you can post a pic & schematic reference.
--Does nothing when you try to turn it over-- Are you saying when you turn the key -- no response, not even a noise or click ??

 

[btodd1]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Sorry guys I try to reply at work and it doesn't work.
OK, I'll make it short. To answer what HOT HOT HOT Means. I turn the key to ON. Not to start, just ON. I walk to the back of the boat. Look at the electronic choke, grab the wires and my skin is burned. I mean super hot! If I touched it for more then a second, I would need first aid for burns. Try to start: NO response, not even a click. UPDATE: This afternoon: Bought new ignition, and Starter Solenoid. Now from dash to stern I have New, Ignition, New Startor Solenoid, New Battery, Eveything else seems to work fine, dash lights, fish finder, etc. Turn the switch to on. Super hot choke wires. I'm going to start looking for a short.........I can get pictures of the choke wires i'm taking about but I don't have the schematic at this time.

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Great progress! Do you have saccessto a dvm? If so you may want to disconnect the wire & take a resistance reading on the choke coil. You could then disassemble it & look for something causing the short or replace the choke coil & compare he reading when your done.

Does the wiire connect to anything else ? If so that could be contributing as well.

Good lucj!

 

[nola mike]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Great progress! Do you have saccessto a dvm? If so you may want to disconnect the wire & take a resistance reading on the choke coil. You could then disassemble it & look for something causing the short or replace the choke coil & compare he reading when your done.

Does the wiire connect to anything else ? If so that could be contributing as well.

Good lucj!

If he had a true short, he should be blowing a fuse. Just disconnecting the wire will take the choke out of the equation however. Still doesn't sound like OP has gone through the starting troubleshooting steps though, so really we're still just guessing. He could also just disconnect the resistance wire altogether temporarily. It should still turn over, just won't stay running.

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Nola Mike
Sounds like you have a similar boat. Does your wire get too hot to touch ?? If not-- Any chance you could provide a resistance reading from your choke heater.

I suspect the choke heater may have a partial short -- as in low resistance but not 0 ohms / Or perhaps something else in the ckt is acting up if the same wire feeds it ( ignition coil or mis-wiring of something ??? )

 

[btodd1]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Wow, I was able to reply at work! Awesome! OK, Guys, I am going to do as suggested and check the starting stickys. Here is my problem. LOL - I'm feeling blind! I cant seem to track down the "Adults only Sticky" area. Can someone post me a link. Then I can just go directly to them. I appreciate it. Still won't start, UPDATE: I did remove the purple/vilot wire connection clip from the carb choke. There they be all by themselves sticking straight up in the air disconnected from choke diaphram. Turn key to "ON" they get hot as hell! So the short/problem/meltdown/ <---- (sarcasim) is coming from another direction. Hopefully the sticky will help me trouble shoot this problem to success! Thanks again guys for all the help and information!
Bret :0)

 

[btodd1]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

If he had a true short, he should be blowing a fuse. Just disconnecting the wire will take the choke out of the equation however. Still doesn't sound like OP has gone through the starting troubleshooting steps though, so really we're still just guessing. He could also just disconnect the resistance wire altogether temporarily. It should still turn over, just won't stay running.

OK Guys! going through the sticky! Making sense now. I got stuck here:

"If the test light did not light up, then the problem is 1 of 3 things either the connection at the main engine harness plug is bad, or you have a bad neutral safety switch or a bad connection between the ignition switch and the slave solenoid.
If you are at home, this isn't a problem and you can track the problem down."

Test light did not light up on Terminal C Yellow/Red wire on the slave solenoid with good ground. I even tried Terminal A Red/Pink wire on the slave solenoid just for grins and NO light on the test light. So I have the 1 of 3 problems mentioned above in the clip shown in the troubleshooting guide.

Thanks, Bret :0)

 

[btodd1]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Boat is running. Thanks for all the support and suggestions. It was the troubleshooting starting sticky that got me through. Thanks nola mike for pushing me in that direction. Thanks everyone for all your posts. After finding out it's one of 3 things in the sticky, I started on the main wiring harness in the engine compartment. I disconnected the battery and pryed the white block connector apart. I tested the wires and got power then put electrical contact spray and pushed it back together. What do you know, engine started and ran fine. I did note that althought the choke wire did not get hot as fast, It still ended up getting pretty hot to the touch. So I'm still wondering about that. But the boat is running so I'll just have to keep and eye on that.

Thanks again all!

Bret

 

[wellcraft-classic210]

Re: Phantom Wiring Issue 1985 Larson Citation 175. Mercruiser 170 - Alpha 1 sterndriv

Glad your up and running -- Thanks for posting the results --