Someone please tell me my motor isn’t shot

[Bigfoot0220]

Hi everyone. Family bought our first boat a month ago, 1995 trophy with 4.3 LX MerCruiser. Took it out twice, no issues. 3rd time out, started up, ran out to fish and when we went to leave, cranked very weak crank like the battery was low. Ran in with the kicker and kept trying to start the main from time to time, same result until finally the starter just spun and whirred, with no flywheel engagement.

Today I replaced the starter, which entailed removing the exhaust manifold and riser for access. (I read MANY a post on here to figure that one out). Put it all back together and went to start, had a strong crank but wouldn’t fire. Kept cranking for several minutes, no change. Then, it cranked for about a second and turned into a grind. Now, each time I try to start I get about a second of crank then it turns to a grinding noise. I turn off the key and the bring continues briefly after key off. I can’t tell whether it’s the starter of an internal noise.

I’m desperate for ideas, and even more desperate to know that the motor isn’t shot. We are crushed by this development, we were planning many outings and trips this summer as a family and our 5 year old is devastated. Any help is greatly appreciated.

thank you.

 

[QBhoy]

Pull the plugs and look for water. Worst case...your flywheel has stripped teeth.

 

[achris]

Hi everyone. Family bought our first boat a month ago, .....

Did you do, or have done, a full service before heading out into the briny?

Most people selling a boat will not have kept the maintenance up, so once you've towed your new 'pride and joy' home, approach it like it's just about to collapse on you, and treat it to a complete and thorough service and inspection. Boat, engine, drive, trailer. Give them all the complete works....

The sounds of your problem could be a multitude of things, as bad as the drive was run low on oil and ate up the gears in the top box, or as simple as a bad ground connection between battery and engine block...

The first thing you need to do is remove the drive and try again... That 'halves' the area to be looking in... (if you do manage to get the engine started without the drive, make sure you have a hose in the water inlet passage of the bell housing so you don't destroy all the rubber parts in the exhaust path....)

Chris........

 

[Scott Danforth]

as Chris stated, assume the PO did nothing for maintenance for many years

first order of business with any new to you boat

• pull the drive
  • do a bellows kit
  • check the gimbal bearing
  • check the alignment
  • check the u-joints
• split the drive and install new raw water pump assembly
• re-install drive
• add gear oil
• change engine oil and filter
• change plugs
• inspect cap/rotor/wires
• clean every battery cable connection from the battery to the block, starter and solenoids. by clean, shiny enough your mother would eat off them clean.
• re-pack trailer wheel bearings
• inspect trailer winch and rope
• service the trailer brakes.

No since you have slow cranking, first thing to check after pulling your drive is your connections

the grinding as Chris mentioned will most likely be something serious.

 

[Bt Doctur]

Sounds like water in a cylinder or two, as stated pull the plugs ASAP , spin the motor to remove any water.
Next remove the drive,reinstall plugs any try to start motor. If it starts let it run for 10 seconds and shut it down , wait 5 minutes and do it again get the motor running to dry the cylinders.
Next change the oil and filter ,water is in there too.
Take the boat out and run the snot out of it for a few hours to get all the moisture out.

 

[Bigfoot0220]

Thank you for the info. I will try to pull some plugs when I get home from work and check. I guess when the manifold was off would have been a good time to do that.

As far as maintenance, the guy I bought it from was pretty meticulous, and has many records. It was winterized and ran many times this spring before I bought it. He has been contacted and is being very helpful in trying to get us all the info he has, I do not believe he knew of any issues. All the fluids were checked and were good. no water detected in oil when I bought.

I do not know a lot of how these motors/drives operate. I figured the outdrive only operated when it was in gear, but the comments seem to indicate that a bad drive can cause staring issues? If the drive is removed, will I be able to inspect the flywheel? I did check when the starter was out and teeth looked fine, but I did not try to rotate the motor by hand to look any further.

 

[Lou C]

The upper gears are spinning anytime the engine is turning and the lower gears are as well, its just that in neutral they are not turning the prop shaft but freewheeling on the prop shaft. So if the drive was run low on oil and the gears and bearings wore that could be part of your problem; did you notice any whining or howling when running it?

You can remove the drive and then try cranking it with the ignition disabled, but first I'd pull the plugs to check for water in the cyls. If you find water then you need to check the exhaust carefully. If its a 1995 that's before Merc changed to the dry joint exhaust so there is a possibility that the elbow gaskets are leaking or the elbows and/or manifolds can be rotted out and causing leaks into the cyls.

 

[nola mike]

as Chris stated, assume the PO did nothing for maintenance for many years

first order of business with any new to you boat

• pull the drive
  • do a bellows kit
  • check the gimbal bearing
  • check the alignment
  • check the u-joints
• split the drive and install new raw water pump assembly
• re-install drive
• add gear oil
• change engine oil and filter
• change plugs
• inspect cap/rotor/wires
• clean every battery cable connection from the battery to the block, starter and solenoids. by clean, shiny enough your mother would eat off them clean.
• re-pack trailer wheel bearings
• inspect trailer winch and rope
• service the trailer brakes.

No since you have slow cranking, first thing to check after pulling your drive is your connections

the grinding as Chris mentioned will most likely be something serious.

We should probably have a "what to do with my new money pit before I get on the water" sticky, this is a nice start. ..

 

[Scott Danforth]

I think most of it is covered in the stickies, however I can look and then ask the mods

 

[Bondo]

We should probably have a "what to do with my new money pit before I get on the water" sticky, this is a nice start. ..

Ayuh,..... I think it's in the thread,.... "Oh, No,.... Don't buy a boat with a,.... OMC, Merc 470, Volvo 2.3l",.......

 

[Blueghost924]

I do not know a lot of how these motors/drives operate. I figured the outdrive only operated when it was in gear, but the comments seem to indicate that a bad drive can cause staring issues? If the drive is removed, will I be able to inspect the flywheel? I did check when the starter was out and teeth looked fine, but I did not try to rotate the motor by hand to look any further.

Where are you located? A well seasoned boating vet may be able to drop by and help out. That outdrive (sterndrive) is always operating when the motor's running. They're connected together with a coupler and u-joint shaft.

 

[nola mike]

Ayuh,..... I think it's in the thread,.... "Oh, No,.... Don't buy a boat with a,.... OMC, Merc 470, Volvo 2.3l",.......

Well obviously I missed that thread
i actually still don't see it...