Generator won't start; troubleshooting ideas?

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ranger58sb

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Ranger
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58' Sedan Bridge
Our Kohler 8EOZ won't start. Yanmar 3TNE74 engine. Not finding solutions in the Kohler and Yanmar service manuals.

Last time we ran it was approx early Oct, maybe Columbus Day or thereabouts... then we didn't happen to try to start it again until approx 9 Nov, i.e., four days after we left home on this current ICW trip. When we tried, that time, it failed to start.

I think I closed the seacock almost immediately...

The symptom now is that it seems the starter is engaging, but the crankshaft only moves about an inch, then maybe returns to original location, can't quite tell...

And I can bar the engine over manually.

Once we eventually landed in Jacksonville last week, we did a load test on the 10-year-old battery. Sure enough it was likely an issue, possibly the original cause, even though voltage tested at around 12.7V (dropping to 10.3-ish during a start attempt). Got a new battery delivered today, no start, same symptom. Haven't (yet?) done a load test on the "new" battery, but one generally expects a new battery isn't likely the cause.

I know what hydrolock (hydrostatic lock) is, but I think I closed the seacock almost immediately... And I can bar the engine over manually.

Could it be hydrolock anyway? I've got feelers out to find a good Kohler generator tech in Jacksonville... but if it's hydrolock, is there something I can be doing myself in the meantime?

Naturally the starter and battery/ground connections are on the backside, and physical access there is likely gonna need some carpentry through a stateroom...

-Chris
 
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You an try closing the sea cock, removing the injectors, and turning over by hand. If there is water in there, I'd expect that to force it out. If that turns out to be the case, you might want to get a mechanic to check things over before starting it up again.

Given that the engine is turning over by hand, especially if it is turning easily, I'm suspecting that your problem has more to do with the starter, or something related to the starter, than the engine, itself.

Good luck!
 
Could it be the glow plug? This is what was causing our generator problems this summer.
 
No glow plug... I think. Not mentioned in the manuals, anyway...

I was just down there assessing access... and checked the oil, looks new. And in fact, I had just changed the oil prior to this trip, 10/13, and probably the last time it ran was right after that.

Larry was just here onboard for a few minutes; he said if I could bar the engine over, hydrolock wouldn't be likely at all.

When I bar it over a bit and try again, the symptom is the same; just a bump, no full rotation, crankshaft is probably returning to where it was...

Of course the starter and battery connections are on the back side of the genset, not visible, not reachable (at least by me) from the front.

I can get the removable sound shield panels off of the front (fuel, oil, and zinc and impeller service), right side (belts and pulleys), and top. The rest of the frame pieces look like they're riveted to each other, not really separable, but maybe there's something I'm not yet seeing.

IF the removable top panel is off, and IF somebody knew what they were doing in the blind, it might be possible to short the starter with an arm over and long screwdriver or something... just to test. (Larry suggested I use an OLD screwdriver :) if I try that.) Or maybe someone could wack the starter with a hammer, in case it's just stuck. Not sure I could do any of that myself, though, given I'd probably be swinging blindly, even with the flexible endoscope thingy...

Looks like to access the back side from down in there by rotating the genset, first it would take removing all port side batteries, disconnecting all fuel and water hoses, removing the generator battery switch, possibly removing some of the PEX freshwater plumbing... and then I'm still not sure it would rotate...

Otherwise, to get to the backside with the generator in place, looks like a carpentry job first -- to cut an access through the guest stateroom. I don't have much in the way of carpentry tools on board...

-Chris
 
When you bar it over you need to make two complete turns CW to completely discount hydrolock or other types of binding.
 
Probably an electrical problem. Bad starter solenoid, corroded connections, bad cables, bad ground.
 
When you bar it over you need to make two complete turns CW to completely discount hydrolock or other types of binding.

Ah. Thanks, didn't do that. It wasn't all that difficult to turn...

I should have called you when we were approaching Wrightsville Beach. Especially since it turned out we had an unscheduled 2-day weather layover there <sigh...>



Probably an electrical problem. Bad starter solenoid, corroded connections, bad cables, bad ground.

I won't be surprised if that turns out to be the case, although given location that looks like the more difficult problem to solve. 10 minute job on the bench might be a 3-day job to get to it (10 minutes to fix it) and then clean up afterwards.

I wonder if the whole thing could be tilted forward, so that the back of the genset temporarily becomes the top. Probably depends on how it's bolted down to the platform it lives on, and I don't know if there's really enough overhead space to allow that. Would likely still require removing the port battery bank first, but maybe all the other connections could remain as is...

I've got a call in to a local fix-it place, happens to be both a Cummins and Kohler servicing dealer...

-Chris
 
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Sounds like you are taking the right approach. Throw money at it, solves most problems!

pete
 
Yep, money fixed it. (So far, knock wood...)

Turned out to just be the battery switch. Replaced.

The young tech did get jumpers cables to the starter behind the genset; he's MUCH younger than I and MUCH slimmer than I've ever been in the last 60 years or so... and he said he was for a time almost stuck back there, too...

Anyway, that's what led him back to the battery switch.

As it turned out, I could have tested that, but probably only by using jumpers and a different battery source than the original generator battery. Didn't think to test that, at the time though, was more focused on the starter possibility.

We had an electrician on board several days ago talking about a different project, and while he was here he did a load test on our 10 year old battery, it was pretty long in the tooth and the test said to replace. Did that, new 34M-PC1500, free delivery from Amazon, but that didn't fix the non-start problem. Given the load test failure, I don't mind having a new battery too.

-Chris
 
KISS principle in action. It is easy to overlook the simple things because we are so worried that something major went wrong and we jump into the major stuff right away. Glad you got it fixed.
 

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