Starter Diagnosis confirmation and replacement help

[mmwjr]

Well that really sucks. Yup the engine needs to come out and the flywheel replaced. I’d do a new starter as well. Get a quote for the job and call around to compare quotes.

[mrt214]

Looks like that tooth has been gone for a good while.

[LaborOfLove]

Originally Posted by mrt214

Looks like that tooth has been gone for a good while.

Right??? I feel like one tooth wouldn’t make that big of an issue. Over time I’m sure it’s possible it could wear out a starter but seems like it wouldn’t halt everything if only that one tooth. Plus the engine was turning just fine for the first few seconds every time. It sounded like the starter was not engaged at all, not slipping in place. And the teeth next to it show very little wear. Bottom line is that hauling the engine isn’t really an option financially at this moment. If that’s the only option I’ll have to look to selling the boat as is, which would be an amazing deal as everything else is in such great shape.

I get that putting a new starter in might be a longshot, but how much labor are we expecting here? I feel like it’s worth throwing a new starter in and testing to see if it did the trick. should be a 2 or 3 hour job tops from the marinade. Is that realistic?

[mmwjr]

While a new starter may resolve the issue for now the problem will come back in time. It’s you money so your call.

[LaborOfLove]

Update here. Marina installed new starter and she cranks beautifully. But...now won’t start. Ugh. Quickly checked for spark tonight which was good. Thinking it’s a fuel delivery issue as she ran fine last year. I tried my normal 2 pumps then 1/2 throttle to start and didn’t even get a slight cough out of her. Maybe gummed carb or fuel filter. I even put the throttle all the way down and no combustion. Will need to troubleshoot another day. That said, would the fuel pump shut off if they didn’t wire the starter back correctly? Could that be my issue? I didn’t check to see if I could hear the fuel pump when I was down there, but now after the fact don’t recall hearing it run. I’ll have to check that the next time I’m down. I specifically remember hearing it run last week when I was troubleshooting the bad starter, so I know it was running before.

[mmwjr]

Don’t see where you said the year of the boat. Being 4.3s they went to electric fuel pump around 1993. When starting the pump gets power from the starter soleniod and once started a oil pressure switch provides the power. Sounds like they miss wired it. See engine manual under Documents for correct wiring.

[mmwjr]

Try this googling mercruiser 4.3 wiring diagram

[LaborOfLove]

Thanks. I see what you mean. I’ll look into it tomorrow and report back. Thanks!

[LaborOfLove]

Got down here today and tried a tiny bit of starter fluid. Started right up for a second. So it’s a fuel issue. Now I can get her to start with 2 pumps on the throttle, but can’t keep her running for more than 30 seconds. Even if she’s running at 2000 rpm with the throttle still opened up a bit she just drops out. When idling at 600 rpm she seems to last a few seconds longer. Could it be a fuel pump? Or something else?! Thanks again.

[LaborOfLove]

Other thing I noticed was that it revs about 200 rpm right before it craps out.

[donald]

Is it a mechanical or electric fuel pump?
If electric I would agree with Mike that it is miss wired when starter was replaced.
Don

[LaborOfLove]

It’s a 2002. Electric fuel pump carbed engine. I though about the wiring and asked them to double check which they said they did. I also looked at it and could see the purple/yellow fuel pump wire on the correct connection on the starter. Very hard to see but here’s a pic too.

[LaborOfLove]

Starter wiring pic

[LaborOfLove]

I understand the pump gets power from the starter when starting and then from the oil sensor once running. Maybe they disconnected the oil sensor connection and didn’t reconnect? Anyone know where that would be so I can check? Also I can see fuel shoot into the carb when doing the 2 pumps, but don’t see any other fuel getting in there while the engines running. Should I be able to see fuel squirting in while idling? Thanks again everyone!

[mmwjr]

The oil pressure switch is on the rear port side of the engine where the oil filter is or if a remote filter where the lines attach to the block. It will have two wires. Sometimes the switch goes bad, you can test by jumping the wires together.

[LaborOfLove]

Hi All - thanks for all your help. Turns out all the drama was actually over a bad connection to the oil switch. Tested it today and she ran great with a jumper on the connection. Cleaned the leads and reassembled and the boat ran as good as ever. Very frustrating that the marina couldn’t figure this out. Get the sense they are a bunch of crooks. They tried telling me it was a blown engine with no compression that why it wouldn’t start. Without doing a compression test mind you. Said I needed a new engine. Total crooks.

[mmwjr]

Glad you figured it out. Time to find a new mechanic.