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  #11  
Old 08-05-2008, 11:50 PM
TMCNo1 TMCNo1 is offline
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Quote:
Originally Posted by ryangraham View Post
thanks andy, i've got a voltmeter. i'll get after it in the next couple days. thanks for the tip.

i'm considering a rewire job. does anybody know where to find the best wiring diagram?

-Ryan

This is from Ski King, he may have more, http://www.mastercraft.com/teamtalk/...62&postcount=3
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Last edited by TMCNo1; 09-16-2008 at 04:44 PM.
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  #12  
Old 08-08-2008, 08:58 AM
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ryangraham ryangraham is offline
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problem solved

i've been bad about posting problems, getting advice, and never posting my solution. i'm not going to be like that anymore. i fixed my problem, and this is what it was....

I had an older starter solenoid (some call them starter relay) that's mounted to the block next to the engine breaker, and it went bad at the beginning of this summer. I bought a new one and installed it being extremely careful to wire it back EXACTLY the same way the old one was wired in. Turns out who ever wired the old one did it wrong. For some reason there was a wire coming from one of the ballast resistor posts (the one that shares the wire with the coil) to the "I" post on the starter solenoid. I noticed that when the key was turned to the on position for only a short few minutes, the "S" and "I" posts on the starter solenoid got super hot to the touch. I noticed this while testing the voltage across the stater solenoid (of course finding that no juice was flowing through it. This was my first clue that something wasn't right. So I disconnected the errant wire and like that the starter turned right over. Apparently the incorrect wiring was causes a short in the starter solenoid that was preventing it from doing it's job of sending current to the starter.

Lesson learned: on an older engine, even if it's been working for a while and especially if you're not the original owner, it's a good idea to check all your wiring. It's amazing how simple the wiring for these old engines is. Thanks King for the wiring diagram! In about 15 minutes I was able to trace out the wires for the entire system and know exactly that everything was wired up correctly except for my one problem area.

Side note, and another question: I used the wire that was incorrectly installed as a jumper, to jump the ballast resister just as the wiring diagram shows and as instructions regarding EI suggest. The distributor does have EI in it. When I did that, the engine still runs fine, but the Tach goes hay-wire. It bounces all over the place, and obviously gives no accurate reading. Oddly, when I turn the blower on, the tach functions normally. It seems to me that when the ballast resistor is bypassed, too much current it flowing to the coil (where the Tach wire is connected and getting it's reading) and the Tach goes bonkers. When the blower is on, it draws down enough current to make the Tach behave normally. That's my theory anyway. So to get a couple runs in yesterday, I disconnected the "jumper wire" and had at it. My question for you guys is this: I know EI wants the ballast resistor bi-passed (jumped) I guess to get full juice in the coil, but is it necessary to do so? If so, then does anyone have a solution for my Tach? Is this Tach gauge rated for a lower amperage, therefore not behaving properly when the ballast resistor is jumped? If so, do I need to buy a new Tach? Is there a way to re-wire something to make the Tach work right?

Thanks again everyone!
Ryan
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  #13  
Old 08-08-2008, 11:06 AM
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JimN JimN is offline
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The resistor needs to be bypassed only when cranking but the EI manufacturer may/may not need it- contact the company. I talked to Sierra a couple of weeks ago about this issue and the tech guy told me that it is needed, so....

The solenoid will have a crank wire and another that goes to the coil, which is the bypass wire. If the coil has another purple wire, the resistor usually goes to the end of the wire and the coil. That should keep the tach and EI happy. If the EI doesn't have the resistor, the wire from the coil can fuse, which is what happened to the boat I called about.
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  #14  
Old 08-11-2008, 12:39 PM
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ryangraham ryangraham is offline
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electrical issue persists: I was out this weekend with the engine running pretty good, tach issue gone. Mid day Sunday, I cranked it and the starter wouldn't stop turning. Pulled the battery cable. I had kept the replacement starter solenoid, so I took 15 minutes to replace the old one. I I wired everything up exactly as the wiring diagram above shows, and cleaned all the wire connection points and scrapped clean the block where the solenoid mounts. Engine cranked stronger and faster than it has in years. So the problem seemed fixed, but later that day, it did it again (starter kept running). I disconnected the battery, gave the starter solenoid a couple taps with a screw driver handle, all seemed fine. I know it is possible that I could have purchased 2 bad starter solenoids in a row, but that seems a bit suspect. I'm starting to wonder about the wiring. maybe an incorrect wiring issue is burning up the solenoids. is the "I" post supposed to be used? the above diagram only shows the "S" post in use. Jim, you mentioned the solenoid having a crank and coil wire. It makes sense to me that the crank wire would be the "S" post (starter) and the coil wire would be the "I" post (ignition). Since my Tach issue is resolved (I blame it on a bad starter solenoid), I'm now trying to figure out this new starter issue. I think it's either that my wiring is off, or I have another bad starter solenoid. The later seems less likely, even though it is possible. Does anyone have any insight on my wiring question, or just this issue in general?

Thanks,
Ryan
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  #15  
Old 08-11-2008, 01:13 PM
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JimN JimN is offline
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Did you remove the starter when you replaced the solenoid? Has the starter been removed sine you bought the boat? Did you know that the Bendix gear and shaft are supposed to be lubricated annually?

If the Bendix shaft rusts, and I will assume it has because of the rust I saw on the head in the photo of the solenoid, the gear will bind when it cranks. You won't have any idea when, until it does, either.
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  #16  
Old 08-11-2008, 01:21 PM
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ryangraham ryangraham is offline
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the photo posted was not of my boat. my solenoid is actually the older style that is bracket mounted so the solenoid sits away from the engine block. there was a little bit of rust that cleaned off easily, but not nearly as rusty as that photo. yes, i pulled the starter off just last week. did not lubricate it, but i will. what kind of lubricant and where do i apply?

still, the Bendix shaft could be rotated by hand, so I'm not concerned about the starter. i bought the boat about 8 years ago, and replaced the starter about 4 years ago. I keep the boat pretty darn dry in storage, therefore the engine is not that rusty and pretty clean over all. again, i really do not suspect the starter as being the culprit. however, i read someone say that the starter gets its ground from its contact points with the flywheel case. while i think this too is clean and not the issue, i will check it and sand/clean as needed.

any thoughts out there on my wiring question and why my starter sometimes keeps cranking?
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  #17  
Old 08-11-2008, 01:42 PM
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JimN JimN is offline
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White lithium grease is fine. Marine grease but NO WD-40! That has cutting oil in it.

Rotating by hand is one thing, climbing up the shaft is another. You'll need to turn the gear in the opposite direction of what you do to just rotate it. It will automatically move up the shaft when you do this.

You may keep the boat dry in storage but you can't really do much about condensation when it's experiencing a temperature inversion.
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  #18  
Old 08-11-2008, 06:38 PM
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ryangraham ryangraham is offline
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Jim, are you trying to tell me that my starter may be the cause of the starter continuing to run after the key has been returned to the on position (from the start position)? To me, greasing something sounds mechanical in nature, while the starter not shutting off seems electrical.

Anybody know what the "I" post on the starter solenoid is used for?
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  #19  
Old 08-11-2008, 07:05 PM
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mad-dog1 mad-dog1 is offline
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Ignition but nothing goes to it....I had the same problems and I just replaced the starter relay and problem solved....look at the diagram again and you'll see....
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  #20  
Old 08-11-2008, 08:38 PM
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JimN JimN is offline
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Without being there, it's hard to say exactly what is happening. If the starter motor draws excessive current, the contacts will stick together, as if they were welded, which can happen. It could be the ignition switch, too. If that shorts or the terminals touch, it'll do the same thing. The only way to come up with a definitive answer is to test for voltage before cranking, while cranking and after releasing the key.
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