Boat started on its own, no key. Mercruiser 165 starter/solenoid/USER error

oldboat1

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inclined to think of wiring too, but mounting/installation/shimming issues are good leads to explore (above). I had a Chris Craft with a 305 that required shimming for the starter gear to engage the flywheel. But mounted or shimmed too far into the flywheel, and the bendix would bind. Possible, I think, for the gear to remain partially engaged in a case like that -- gear wouldn't descend down the starter shaft (ratcheting sound).
 
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H@ystack

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Definitely appears mechanical over electrical. For now, I can only compare photos of other starters online, but I think this starter he rebuilt has the driving pinion sticking up too far. The spring pulls it back when engaging it manually by hand. But I'm almost betting the starter wheel actually overshoots the fly wheel and when it pulls back doesn't have enough clearance. I wish I had a photo of the starter beforehand. I bet that wheel sinks down in the starter more than it does now. I'm going to have him swap starters for me and continue with process of elimination. At least all electrical is solid now. I'll report back for anyone else having issues in the future
 

oldboat1

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That Chris Craft I mentioned -- starter bendix would kick up and spin freely because it wasn't catching the ring gear. But if memory serves (and it might not), the gear would be stuck up at the top of the shaft when this happened, because the flywheel didn't kick it back down. This doesn't quite square with what you describe, but might be relevant: If your starter is only partially engaging, you are likely getting a ratcheting sound -- and maybe the gear isn't retracting down the shaft because the spinning flywheel isn't engaging it and kicking it down (i.e., it stays extended -- locked up there). Could still be a mounting or shimming issue (bendix gear not properly engaging flywheel).

I remember bringing the starter to the rebuild shop for them to check (checked out OK). It's my understanding the shop used a machine that duplicates the flywheel and spins the gear back down on the shaft.

[edit: other conditions that could give you a stuck gear -- weak battery or starter, wiring issue. Starter should really pop the gear up into the flywheel, with power to spin the motor as long as it takes. If it poops out for whatever reasons, the gear can stick up at the top of the shaft.]
 
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H@ystack

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I just called the guy who rebuilt it for me. I told him what was going on. He said there 2 shaft he can use for this wheel. A long and a short. He said the long would put it out too far and cause that problem. He may have mistaken my engine for his old engine that required a long shaft. He said if it is clearing the opening pretty good (which it is), he used the wrong shaft. He said he'll know more when he sees it. Fingers crossed for this issue.
 

oldboat1

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plot thickens..... will get some input from the rebuilder, even if right shaft was used.
 

H@ystack

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plot thickens..... will get some input from the rebuilder, even if right shaft was used.
Yeah man....he's a good dude. I'm from a small town, so when I can I take it to people like him. Ya know, where it's your name on the door. He's been in business for a long time back in my hometown, and if you know small towns, that says a lot. It may be all cash, hand written receipts, and no website/email, but you can always have a decent conversation about your problem. :)
 

oldboat1

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yup know it well (currently relearning it). most good, some not so good. if not so good, think you just sort of quietly wander off to another source -- if one's available.
 

H@ystack

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Quick update for those who may have similar issues are running through process of elimination for all possible errors.

I just got a call from the guy who rebuilt my starter. He said it was all done correctly, except, he added a washer in to the bottom of the shaft that did not require a washer. From what I've seen online, this is one of the ways people "shim" their starter, from the inside. Apparently, he said he rebuilt about 4 that day and may have gotten a couple mixed up. He said the washer is about 2 mm, which he said appears to be where the starter is wearing. When I looked at the fly wheel, it does look to be just slightly nicking the edge of the flywheel, so that would do it.

I'll get it in the boat just to be sure, but this (hopefully) sounds like the problem.

So, just to recap here.

If you're having these issues, get your meter out and check your slave solenoid that feeds the starter solenoid. Make sure it isn't sticking open or closed. Mine actually stuck closed at first, and then eventually open. It was an easy change for me on my boat. The part cost $34 with tax at a Marine store near Melbourne, FL.

My starter definitely needed to be rebuilt anyway, but as you can see, there is certainly a chance it's purely mechanical over electrical. The Starter rebuild cost $125.

I'll report back when I'm floatin' and boatin'. If I come back completely dejected, you'll know why.
 

oldboat1

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feedback appreciated. learning/relearning.... The shimming you describe is different from the "shimming" I was referencing (See Silvertip's post) -- where the shim or shims go between one or more of the starter mounting bolts and the block -- moves the starter and shaft/gear into or away from the flywheel, whatever is appropriate. You are addressing the position of the gear on the shaft. Very interesting (thanks again for the comeback.)
 

oldboat1

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think I can see that, though, Fed. Bendix not correctly assembled (potentially).
 

Fed

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Although I mentioned Bendix in a previous post I don't think they use a Bendix, it looks like the old fork is used on them.
It's been an age since I've had an inline 6.

I'm wondering where they mystery washer was fitted and how much difference 2mm would make to the gear mesh and how that 2mm washer could keep the gear engaged.
Even if the washer was between the gear & the starter motor surely there's more that 2mm clearance between the stater gear & the ring gear at rest.
Bit of a mystery but from what I can see of the wiring on the solenoid it doesn't look right. Time will tell.
 

oldboat1

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no reason for the assumption, but was thinking the washer might be rising up the shaft with the gear, perhaps causing a problem with smooth return of the gear down the shaft.
 

H@ystack

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no reason for the assumption, but was thinking the washer might be rising up the shaft with the gear, perhaps causing a problem with smooth return of the gear down the shaft.


That's precisely what he showed me when we picked it up. The Washer gives a bit more clearance to the opening. It will push the shaft up too deep, or too shallow for some engines.

The wiring is precisely the same as it was prior when the boat was running normally, the relay was just sticking. It was definitely not a wiring issue. I've put a meter on everything, and nothing continued to fire that would continue to push the rod in the starter. I left it running a few quick seconds so I could hit a meter to everything. No ignition wire on the slave or the starter solenoid continued to push volts.

All is well in the world of this boat running normally again :) Everything is firing and starting normally, without the awful metal to metal grinding sound.

Now, I need to enroll at Georgia Tech, become an Engineer and invent a starter that isn't 40 lbs.
 
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