Problem with pre-alpha (MC-1) mercruiser 165 -- not starting?

porchlight

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Hi Chris,
Thanks for the reply... that's what it sounds like to me, too. Really hoping it's just the solenoid or the starter and not like a hydrolocking issue.

I went in yesterday to try and sort out the issue, and my manual says that the starter is right under the solenoid (on my motor, its a large black cylinder.

I didn't see much in the way of wires leading to it, and I just want to confirm that this is the starter. I coudln't get a good photo as it was on the underside, but does this look right?


IMG_9526.jpg

(that's from the bilge looking up)

If so, I'll pull that and give it a check. From the top, it's the black cylinder on the very bottom (under the solenoid) that the arrow is pointing to:
IMG_9153.jpg


Any.... uh.... tips on getting it out? It's pretty tight in there... :/

thanks!!
 

Bondo

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Any.... uh.... tips on getting it out? It's pretty tight in there...

Ayuh,..... That's the starter alright, in yer pictures,......

For Tips,.... Remove whatever's in yer way of gettin' to the starter,......

Just remember where everything goes,......

Pictures help, for those that don't know to begin with,......
 

dezmond

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Also marettes should not be used. Especially in a boat. You should pull the starter and bench test it. Quicker results this way.
 

porchlight

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Hi all,

Just another update. I did some pouring over the manual and looked at starter solenoid specs... figured I could short the actual positive input to the starter motor, so that's what I did as another test...

The starter spun around, which makes me think that something is wrong in the solenoid. But, I had two requests:

One, can people with a more experienced ear than myself take a listen? I only jumped it for a second just to verify that it was, in fact, spinning, but I didn't want to cause damage, so I didn't want it to keep spinning and maybe burn out or something.

video/audio: https://youtu.be/6M9s2ZE1KbU


And two, I was a little disconcerted by how quickly it seemed to be spinning. It almost sounded like it was just spinning freely, rather than turning the motor over... but then again, I've never ran the starter for that short a time and I've definitely never been that close, so maybe it sounded different. Also, the key was off, so the starter motor would have just been spinning, the engine wouldn't have kicked on.


So, does this sound like a normal starter motor? Is this what I should expect when jumping the motor directly?

Thanks again for all the help so far! Hopefully this narrows it down to just the solenoid.

P.S. I also feel like I should address dezmond's post about bench testing it... I apologize, I just noticed that your post was there as I was typing this one up. It wasn't ignored intentionally, and if something sounds wrong or if there are issues beyond the solenoid, I will definitely pull it and have it tested!

Thanks all!
 

Bondo

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Ayuh,.... That's just the starter motor, because you by-passed the solenoid,......

The other big terminal get's battery power, then touch the tiny terminal closer to the block, to excite the solenoid, And the starter,....
 

dezmond

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It's nice to be able to pull them to test them.. Also a good time to clean them up. If in doubt you can take it to a starter/alternator guy and they can check it out for you. No need to apologize. All is good ;)
 

porchlight

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Hi Bondo,
Thanks for the reply... maybe I should have clarified what I was doing and refresh everyone's memory about what's happening...

So, my boat won't start at the moment. Thanks to the input here, I realized that when I turn the key, the starter makes a big click, but the engine doesn't turn over at all.

That led to some worries about it possibly being hydrolocked or worse. The fear was, if the starter clicked, was the engine not turning over because it's stuck, or because there's some issue with the electrical connections?

So I've tried various things like jumping the terminals that Bondo suggested. When I do that, I get the big click, but the starter still doesn't engage. So I still wasn't sure if the engine was locked, or if it was a connection problem, or what. Finally, I had time today to check the actual starter motor. I was intentionally trying to bypass the solenoid to see what happens when power goes to the starter motor.

I was thinking that one of two things could happen: Either: #1) nothing would happen and I would get either no movement or a movement with a big crunch noise, which would indicate to me that something was wrong. Or, #2) it would turn over and sound just like normal, which would imply to me that the issue is somewhere in the solenoid, because when power actually gets to the starter, it starts up.

But I wasn't expecting #3: It would turn over, and there wouldn't be a crunching noise or anything.... but it would sound wrong. To me, who (admittedly) hasn't heard this process up close and probably forgot what it was supposed to sound like, it sounded like the starter motor was just spinning but not actually turning the engine over. And that was with the plugs in and everything. It just sounded like the starter motor was spinning pretty fast, when I vaguely remember it being more slow, and... hard to explain, but you know that chug-chug-chug sound when engines are trying to start, that kind of deep, kinda off-rhythm sound as the pistons turn over and it sucks in and pushes out air? I didn't hear that, I don't think.

So what I was hoping to get from the experts was a) validation that if I get a click but nothing else when jumping the solenoid but then the starter motor turns over when the starter motor is jumped, the issue is likely inside the solenoid, yes?

And b) Does that starter motor sound normal? I only had it on for a split second, and I also didn't have the key on because I didn't actually want it to fire up right next to my head, but I still would expect it to sound... different. I'm hoping that someone will say, "oh, yeah, that's just how those old mercruisers sound when you're right next to them, they just sound like the starter motor is spinning at light speed, that's 100% normal". But I just wanted to verify that it actually does sound normal, because my fear is that it shouldn't sound like it's spinning quite so fast...

Thanks!!


Edit: @Dezmond... it officially looks like I'm ignoring you now... but that time you posted while I was typing this, ha! Thanks for the note. I will definitely clean it up and pull it as a next step, and even if it's fine, I may just pull it to clean anyways... you're right, pulling/cleaning is never a bad thing :)
 

Bondo

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But I just wanted to verify that it actually does sound normal, because my fear is that it shouldn't sound like it's spinning quite so fast...

Ayuh,..... It ain't gonna sound, "Normal", unless you test it, "Right",......
 

porchlight

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Oh. I guess I just figured that I should be able to tell... something... from jumping the starter.

Ok, so maybe y'all can humor me here a little bit, with the understanding that I don't know much about mechanics... but in my head, by bypassing the solenoid and jumping the starter motor directly is "normal" in that as the starter motor turns, it should turn over the engine, even if the key isn't turned.

I guess the question is, which part of my test was "abnormal"—that is, which part should I fix to get a different result? At this point, the most "normal" I can think to start it would be to put it in the water, lower the outdrive and all that as if I'm going to head out, turn the key on, and then.... jump the starter motor. So I think that's my question: Was it just an "abnormal" test in that the key wasn't turned?

Or would I have to do more, and go all the way and replace the starter solenoid, so that the power is going through the solenoid?

I guess I'm not seeing why jumping the starter motor by simply bypassing the solenoid would give a different "sound" than running through the solenoid like normal if everything is working properly. But I also don't understand engines as well as I should, so I'd appreciate any explanation :)

Thank you for all the help and patience so far!
 

Bondo

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So I think that's my question: Was it just an "abnormal" test in that the key wasn't turned?

Ayuh,..... I believe it's explained above,..... The solenoid does 2 things at once,......

Not only does it pass power to the starter, it also shoves the bendix drive into the flywheel, to turn the motor over,......

Position of the key is only supplin' Ignition power if "On",.....
If the key is turned "Off", it supplies nothin', the starter turns because yer jumpin' it,......
'n if you jumper the solenoid, the motor will turn over,......... or not if it, or the drive is seized,...
 

porchlight

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Bondo Oh, I see! Thanks for the explanation. I had no idea that the solenoid also connects the flywheel, I get why you are saying that just jumping the motor won't tell me much.

So, at this point, I feel like the starter motor isn't seized, and when I jump the solenoid I get a big click (which would indicate to me that it's working) but that doesn't seem to actually get power to the starter motor... I'm guessing the issue is in the solenoid somewhere. Maybe the internal connections are corroded, or something....

Thanks again for the help. I'll look into getting a new solenoid and report back when I have it installed!
 

dezmond

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I would still suggest pulling your starter and taking it somewhere to have it tested. The solenoid is attached to the starter so it will be checked as well.
 

porchlight

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Folks,
I just wanted to say thanks. I know that I have been slow working through this issue due to my boat being stored off my property, but you all responded as I tested things out and got the problem narrowed down further and further.

I took the advice of getting things tested. The solenoid wasn't letting current through, so I bought a new one and popped it on this afternoon and it worked!

I just wanted to express my gratitude to everyone who responded. I think this could have been a pretty significant frustration for me, but being able to bounce ideas off of knowledgeable people and get guided input did a lot to keep me on the right track and gave me confidence that I wasn't looking in stupid places. This definitely got resolved faster, cheaper, and in a much lower stress way than it could have been.

Thank you all!
 
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