Help! Short from Bildge causing Hard Starts

SeaRayClyde37

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Jul 26, 2014
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33
Ok guys. Working on an 86' Sea Ray Seville. 224 3.7 170 Mercruiser. Yes i know...the loathed 470.

Stopped on the lake, went to crank and nothing. Went to the back and found a short. It was the positive from the disconnect to the float switch on the automatic bilge touching either the block or the heat exchanger...either way idk.

-Disconnected that and ever since it either cranks right up or turns Really Hard and then stops. Bad Feeling on the water.

Cranked up about 15 times when we got home no problem. I'm wondering if the resistance from the short went to the windings in the starter, starter solonoid, or slave solenoid relay. From starting during the short, i noticed the rubber boot on the starter solenoid at main power melted. Something smoked a little and got hot, either starter or starter solenoid...not sure which.

I would honestly like to just replace all three starter, starter solenoid, and slave solenoid relay. Unfortunately I dont have the money to do it all at once, plus I know how this kind of thing goes...narrow it down to the problem part and replace what needs to be replaced. Problem is...how.

I checked the terminal on the starter solenoid that appeared to get hot to ground and theres no continuity. Cant find any other shorts. Has this ever happened to anyone?????????????? thanks
 
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bruceb58

Supreme Mariner
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Mar 5, 2006
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30,454
You need to disconnect all your cables and clean them and replace before you start replacing parts.

Your bilge pump has nothing to do with your problem and there is no terminal on your starter solenoid that connects to ground.
 

SeaRayClyde37

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If it has nothing to do with my problem then why wouldn't it start until I pulled the hot +12v wire off of the block that was shorted. I had to disconnect it completely from the fuse holder. I was trying to crank for about 5 minutes straight until i found the short. During that time absolutely nothing happened except my starter smoked. When a short happens, a lot of current is drawn to the component with the most resistance...correct? Why wouldn't the starter trying to crank during the short take the load?

Also, the starter solenoid MOUNT to the starter is a ground. There is a voltage drop somewhere. I just have to find it.
 

SeaRayClyde37

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Yeah...the starter solenoid has a constant hot terminal, a terminal for ignition, and a ground mounting stud. The one that seemed to get hot was the constant hot terminal which probably during the short caused current to go from +12 at the battery to the block and through the solenoid during the cranking. No?? Maybe I'm crazy haha. I forgot to mention...I did have to do a direct start with a screwdriver from constant hot to ignition on the starting solenoid. Maybe that did it but. My gut says I need a new starter but supposively they can handle a lot of current.

I should probably make sure the stator is putting out voltage and have the batteries checked before I buy anything too
 
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bruceb58

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Take off the battery cables and clean both ends and reinstall first. The fact that it got hot indicates a resistive connection.
 

bruceb58

Supreme Mariner
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Mar 5, 2006
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Do the same for the ground cable that goes to the engine block.
 

SeaRayClyde37

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Jul 26, 2014
Messages
33
I don't know. It cranks right up out of the water. Cables look ok.

I have a questions about the starter solenoid. How does it work and why is there constant 12v terminal and an ignition 12v terminal from the slave???
 
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Feb 17, 2012
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2,906
slave is acting as a relay to reduce the load on the ignition key. On most models the starter solenoid is not only a solenoid for the 12v power but it is also the mechanical solenoid that pushes the bendix into the flywheel. This set up requires more power at the starter solenoid so the a slave supply's the power.
 

SeaRayClyde37

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Jul 26, 2014
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I took everything apart and cleaned every contact surface and put it back together. It fires right up so I'm not messing with it anymore. Going to take it to the lake this weekend if it doesn't rain. Ill keep yall posted. Thanks again for the input
 
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SeaRayClyde37

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Jul 26, 2014
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ok guys so just got home from the lake. Everything went fine untill we were on the water a couple of hours. When it gets hot it cranks hard. I got super lucky that it finally cranked today. The gauge never went above like 150 160ish. Is it possible to change the thermostat to something that will open at a little lower temp? Also noticed coolant was low. Added like 2 quarts...not normal right.

I ordered a thermostat and impeller. Precautionary measures. I've only had the boat for a couple weeks so I figure might as well do the cheap swaps.

I think I need a starter. It just doesn't turn when its hot. I found one on amazon for $150 by Sierra.
 
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SeaRayClyde37

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Jul 26, 2014
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33
Replaced the starter. Turns over nicely. Ran like crap for a few minutes..now nothing. Bad slave or coil?
 

SeaRayClyde37

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Joined
Jul 26, 2014
Messages
33
Had 12v at the coil. Starts with a lot of throttle. Electrical is doing its job. Carb is soaking in a gallon of cleaner. It was pretty bad. Rebuild kit should be here in a day or two. Let the fun begin.
 
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