New to the forum but have found a lot of sage advice in a short time.

I recently bought a boat with a 2003 6.2L 377 Merc. Good price and relatively clean but I knew she needed some work.

In short order I found a fuel leak which ended up coming from Cool Fuel rail under oil pan. Engine had to be pulled to reach it for replacement. While engine was out, I put new Merc risers and manifolds on it. Ran it on the stand. Started and ran fine. Shut it down for adjustments and the starter went. When I checked into it, I found the previous owner had put a rebuild starter on it recently. So, I pulled the started and took it back to the rebuild shop where, without question or charge, swapped it out with another. It was installed and engine started fine and ran great.

A few days later the engine was installed on boat and I started running it. I ran offshore for a night cruise and upon return to the boatel, I shut her down to offload and when I went to restart her to flush the block "bam", starter went again! So this is three starters in 1.5 months. Each one is getting about 10 to 15 cranks/starts at the maximum!

- So I pull that starter, which was a lot more difficult in the boat than on the stand. I took it to the shop again where they rebuilt it and had it back to me in a couple hours.

-While starter was being rebuilt I jacked the engine over with socket and ratchet. Met some compression but didnt seem to hit any brick walls like I would if I had hydro lock.

-Then I started pulling plugs one at a time. Tapping them on dry paper to see if they had any moisture or condensation in them. No water to be found and the plugs appeared to be showing normal carbon build up and wear(not super clean as one might expect if they were getting wet).

-Then I hooked up the hose and ran water through the block withouth running it as the plugs were still out and didnt have a starter yet. I did this for about 10 minutes and checked all the cylinders for water/moisture. I did it two more times and found absolutely no sign of water in cylinders.

-When I got the starter back, with plugs removed, I had my hired help(my son)hit the ignition and the starter did its thing. With no compression due to plugs being out, it turned over easily enough and there were no signs that the cylinders were spitting water out of the spark plug hole. I had laid over the engine and was eyeballing the plug holes on the Starboard side while he turned the key. I felt the compressed air blowing out of each of the cylinders on the Stbd side but got no moisture. With that in mind, I gave each cylinder a quick spray of fogging solution and installed new plugs since the old plugs were out and I figured good time to do it.

-Then I ran the engine on a hose to let it warm up and pulled plugs again. No water to be found.

-This past Saturday, I trailered the boat to a ramp on the Eastern Shore by the Chesapeake Bay Bridge Tunnel. Loaded it to capacity with family and friends, ran to the barrier islands, towed some wakeboarders and hit the TIKI Bar at Sunset Marina. Nice time!!!! When I got back to ramp, I shut boat down to offload and when I went to start it to get it trailered the started went again!!!! 4th time!!

Standard convention says hydro lock, but I dont think that is the case. I havent had the chance to do anything with it yet and it was dark so I couldnt see much, but I want to do the following:

-Check voltage to starter to make sure it is getting enough to engage Bendix.

-Check engine again for signs of water in cylinders.

-I bought a compression gauge and hoses to check compression.

-While I have the starter off I am going to check all contacts between wires and lugs. Clean them well for reinstall.

-Also, while starter is removed I want to jack the engine over and "feel" for broken teeth on the flywheel. Trying to get a camera and lite so I can film it through the access where the starter goes so I can actually see the teeth on the flywheel.


I really could use some good advice on this and have seen that this is a good forum to get educated from.

BMCS

is it top mount or bottem mount starter what is the timing set at if it is a top mount starter you cant use a rebuit starter i went thru 5 then bought mercrusier starter it seems to be good now how fast does it crank when you turn it over

Who is rebuilding the starter? If its HARCO find another rebuilder. Sounds to me like that is your issue.

It is a bottom mount starter. Aft Port side. Real difficult to get to so would like to mitigate everyting I can short of pulling it. Not clear on what you are asking about top or bottom. Not familiar with top mounts. Cranks fine, but when it went the starter motor just spun very fast.

It is a local shop with a good rep. 3 failures???? I am pricing out an Merc OEM starter.

Black Baja, I had read one of your forum posts on a similar matter dating back to 2010 and found it promising. Glad you are still on Forum. RunninRagged and you both seem to lean toward a series of bad starter rebuilds. I know the rebuild shop turns them around in about 1.5 hours. I also know that when I pulled the starter off the engine while it was in the boat, the shop had not yet opened so I was passing a auto parts chain that tests alternators and starters. Took it in and they put it on their bench and it tested out fine. I kind of disregarded that in favor of what the rebuild shop later said, that it was bad. Figured the rebuild shop would know better than a kid at an auto parts store.

is the motor cranking slow and kicking back what broke on the starter did you check timing if its to far advanced at start up

Cranking fine it seems. It just aeems to go soon as i turkey. Before it engages bendix, starter motor races at full speed . No crank, ni backfire, nothing that would indicate imminent failure.

I can turn a wrench pretty good, but haven't checked timing in anything since my first car. 71 Pontiac Ventura

Ni kick back. In fact I have been listening for that but no sign of that at all. If it didn't start immediately, I would stop cranking, let it settle out again, then crank.

get a good gear reduction starter, I went thru three or four before getting a good one, check the grounds and batterys a dead cell will be good one minute and bad the next makes you think a starter goes.