5.7 Mercruiser Starter problem

[sandsmccoy]

Greetings - My apologies for the long post but I want to be certain if you take the time to read it you understand my situation. I have a 2008 2500 SS Ebbtide deckboat with a 5.7 Mercruiser and alpha one outdrive. I've been fighting a starter issue ever since I purchased the boat 5 years ago where the starter will not properly engage the flywheel (it will begin to spin the engine and then pop out) when cold especially after it has set for a few weeks or at the beginning of the boating season. Once you have gotten the boat started and as long as you use it regularly (every couple of days) the engine starts without any issues. I have replaced the starter 4 times and even replaced the engine (new crate engine from Mercruiser). The engine replacement was a last ditch effort to cure this problem and was performed by a qualified Mercruiser mechanic at our local marina. It worked fine for the break-in period (30 hours) and then toward the end of the season started behaving like the original engine (which had roughly 1600 hours). I have replaced starters on GM 350 engines in more cars than I care to count over the last 50 years and have never encountered anything like this. Yes, some of the car starters needed to be shimmed (the older ones especially) but according to all the "experts" you do NOT shim this starter on a mercruiser (however, I have tried and it made no difference). I'm at my wits end and am ready to dump the boat even though its a great performing boat once you get it started. Has anyone else had a similar problem on an engine of this era. Any comments, advice and/or suggestions would be much appreciated. Thanks in advance.

 

[alldodge]

I'm thinking electrical and maybe a bad connection or bad battery cable

 

[Scott06]

I'm thinking electrical and maybe a bad connection or bad battery cable

either that or was the flywheel transferred between long blocks? But have never seen a flywheel kick the starter gear back

 

[Lou C]

It would be interesting to see how much battery voltage drops during cranking.

 

[Scott06]

It would be interesting to see how much battery voltage drops during cranking.

Wonder if it is too low to keep the gear extended?

 

[Lou C]

That’s what I’m thinking of. Somewhere it may be losing voltage due to resistance or even something like a bad assist solenoid.
When I bought my boat (2002) all the cables were in bad shape. I added a dual battery system in 2005 and up sized the cables to 2 gauge for the shorter ones and 1/0 for the long one. Each battery had its own ground to the bell housing. Ever since then no starting problems.
Low voltage to the starter will actually cause the starter to fail due to the low voltage causing the starter wiring to overheat. This is also why you should replace the battery as soon as it gets weak. A bad battery can cause a starter to fail and a bad starter can cause a battery to fail.
Last thing I’ve seen a flooded engine compartment can let water into the flywheel housing & cause rust in the ring gear teeth. This can cause the starter gear to not fully engage or even stick. If you suspect this I’d remove the starter & rotate the engine by hand to inspect the ring gear teeth. I’d clean off any rust and put on a light coating of marine grease. Same on the starter gear & the shaft it slides on.

 

[1985 Century Mustang]

Greetings - My apologies for the long post but I want to be certain if you take the time to read it you understand my situation. I have a 2008 2500 SS Ebbtide deckboat with a 5.7 Mercruiser and alpha one outdrive. I've been fighting a starter issue ever since I purchased the boat 5 years ago where the starter will not properly engage the flywheel (it will begin to spin the engine and then pop out) when cold especially after it has set for a few weeks or at the beginning of the boating season. Once you have gotten the boat started and as long as you use it regularly (every couple of days) the engine starts without any issues. I have replaced the starter 4 times and even replaced the engine (new crate engine from Mercruiser). The engine replacement was a last ditch effort to cure this problem and was performed by a qualified Mercruiser mechanic at our local marina. It worked fine for the break-in period (30 hours) and then toward the end of the season started behaving like the original engine (which had roughly 1600 hours). I have replaced starters on GM 350 engines in more cars than I care to count over the last 50 years and have never encountered anything like this. Yes, some of the car starters needed to be shimmed (the older ones especially) but according to all the "experts" you do NOT shim this starter on a mercruiser (however, I have tried and it made no difference). I'm at my wits end and am ready to dump the boat even though its a great performing boat once you get it started. Has anyone else had a similar problem on an engine of this era. Any comments, advice and/or suggestions would be much appreciated. Thanks in advance.

Have you checked voltage, is it draining, maybe a wiring issue. Bad grounds are usually the culprit? Did you align the engine with the Sterndrive? Sterndrives that aren't aligned can effect the coupler and flywheel. Just my 0.2 cents. If you have done everything possible. I'd get a priest to bless the boat

 

[stresspoint]

is the boat kept in a damp area or is there any leaks that would allow condensation up the starter .
thinking small amount of rust on starter shafts or on FW gears " or" if greased moisture has stiffened it up.

my Holden Caprice (sunny day car) has a similar issue , if i park in the garage for weeks i have no issue , if i park outside especially in winter it just clicks when i go to start after it has sat.
as posted , usually a fully charged battery will give enough kick to get the starter to throw past the build up.

my first thought after the second starter did exact same thing was it was getting too hot because of the proximity to the exhaust header ,so i replaced all the heat shields and added some just as a "well if its that it should be good now",.
the third time i removed it there was sign of rust on the starter shaft which i felt was the issue "TILL" it did it again.

i still have the issue , so i will be keeping up on this thread to hear what people say.

 

[kenny nunez]

It appears that the starter is kicking out in a “false start” mode. I wonder if the same thing will occur with the coil wire out of the distributor cap. If it continues to turn over then then I think it would rule out a mechanical issue.
Also with a remote starter button that you may already have try connecting it to the #10 yellow/red wire on the starter solenoid and the + battery post to completely bypass the start circuit with the coil wire connected and of course with the ignition switch turned on.
Try this after the boat has set up for the period you have described.