Mercruiser 4.3L Engine Problems...

alldodge

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Here is your first thread.
https://forums.iboats.com/forum/eng...ives/10625255-mercruiser-4-3l-engine-problems

You can always find your thread you started by going to your page (click on your name) and look for "all threads started". Figure GA_Boater can put this one back in with your older one

As for a wiring diagram specific for the boat, there normally is none. Only ones which have detailed diagrams are the high end boat builders, the rest just use the standard diagram

Gen wiring Diag 2.jpg
 

bergeronn

Cadet
Joined
Jul 30, 2018
Messages
19
Thanks for the diagram and the information. I'm going to email Tahoe Boats as well to see what they have. Hopefully I can get all power restored.

Now for the possible 'bad news' update. I did drain what I could out of the oil. I ended up draining out about 2.5 gallons of water with a pump that goes in where the dipstick goes. I guess the oil was too thick to go through the pump. At least I got the water out. :) The little oil on the dipstick now looks clean.

I then removed the spark plugs. They all looked wet on the ends. The middle one on the left side was stuck, but once I removed it, a thick black substance, like old oil, came oozing out. Not what I expected. Any insight as to what may be going on? I'm stumped at the moment.

All this because a maintenance shop allowed it to fill with rain water. Ugghhh

 

Jcris

Chief Petty Officer
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Apr 23, 2016
Messages
466
FWIW,
this really is a sad situation. Any reputable repair facility shouldn’t have let it sit outside unprotected Legal recourse can be difficult and has to be weighed against actual value. Whatever you do, consider strongly NOT letting that repair shop touch the boat.
Good luck
 

Rick Stephens

Admiral
Joined
Aug 13, 2013
Messages
6,118
From re-reading, the longest the water would have been in the engine is two months or so. The black sludge could be iron and carbon from the manifold seeping back into the cylinder. Thinks if this was mine, I'd pull the motor and disassemble. All that costs up front is gaskets and some time. The long term wear and tear would be negligible if you clean everything up. Long term is unknown if you assume anything and just clean out and replace the engine oil and fire up.

As an aside, I've been through a similar scenario. I bought a boat with the intention of using the running gear in another boat. Said donor boat had a brand new rebuilt 4.3L V6 in it. The flash arrestor was in a cardboard box and a tarp covered the boat. Nothing but tarp covered the open top carb. Needless to say, the oil pan and several of the cylinders were full of water and the pitting was pretty bad. I got it to crank over, but decided to pull it apart and make it right. Good choice. All those zero hour pistons and rings pulled, bored out another 20 thou, new pistons and rings. I lucked out. The crank, cam, lifters, main and rod bearings were all good since it was never run with the water in it. What suffered was cylinder walls. I spent some time just cleaning things and making sure all was perfect before reassembly and reinstall. Was not very expensive, under $700, to do the entire re-re-build. Make sure you get the FelPro marine gasket set if you do the disassembly. It is the best out there. I got mine from Summit for a fair price.

Rick
 

tpenfield

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Jul 18, 2011
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Just reading this thread as it unfolds, I am glad that I do my own work. I'm sure we are hearing about the few bad experiences with boat shops, and not the good experiences, but to be on the wrong end of the odds seems to be a complete exercise in frustration with little re-course.
 

bergeronn

Cadet
Joined
Jul 30, 2018
Messages
19
FWIW,
this really is a sad situation. Any reputable repair facility shouldn’t have let it sit outside unprotected Legal recourse can be difficult and has to be weighed against actual value. Whatever you do, consider strongly NOT letting that repair shop touch the boat.
Good luck

They are definitely NOT touching my boat again. I can understand not having enough cover for all the boats, but at least do a daily check of the boats in the yard. Had they done that, this wouldn't have become an issue.
 

bergeronn

Cadet
Joined
Jul 30, 2018
Messages
19
Rick,

That's probably what I'll be doing. I've learned so much already about the boat. Wish I knew then what I know now. Would have saved me some heartburn.

As for the sludge, it looks like it was only about a cup or so. I'm also in the process of replacing the starter. I think once I get it removed, that will free up the flywheels. At least I'm hoping so. I know I need to replace the trim as well
I believe the trim motor is shot.

I also found the power issue. I pulled the fuse box from under the steering wheel. Apparently, the wiring harness adapter was corroded. Some wires corroded off of it and some of the pins corroded out of it. Time to fix that.

With all that said, repair the wiring harness, replace the starter, replace the trim motor, then the boat should be running again. Then I'll get the boat to my brother in-law where we can rebuild the engine.

This boat won't be going back to any maintenance shop. That's for sure.
 

nola mike

Vice Admiral
Joined
Apr 22, 2009
Messages
5,687
Don't forget to pull your outdrive. You probably ended up with water in the bellows and a mess in there as well
 

bergeronn

Cadet
Joined
Jul 30, 2018
Messages
19
For the electrical experts out there, this is a picture of my Mercruiser 4.3L Trim Assy. Can you tell me if this looks right? I've placed all the cables back where I thought they belonged, but couldn't find a real good picture online that showed the small red cables from the fuse. Hopefully, you can see the solenoids good enough to determine if I have everything hooked up right. When I go to lower or raise the trim, all I get is a click. Either the wiring is wrong, a solenoid is bad, or the trim pump is shot from the water. Just wanted to check to see if the wiring was correct first.

Just to clear up the picture some, top solenoid is the blue wire (I'm missing the nut. Had to get a new one at work). Below that is the 110amp Fuse with power to it, below that is red wire from fuse, and bottom port is green wire.
 

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bergeronn

Cadet
Joined
Jul 30, 2018
Messages
19
The shop must have done something for that to be unplugged, or someone was getting ready to steal the motor maybe.

Maclin,

I figured out what happened. Years ago, I had some wiring fixed on the boat. Apparently, Bass Pro Shop ran a whole new wiring harness and left the old one in the boat. This happened to be the old one. I'm going to be removing it so that there is no other confusion in the future.
 

greno

Petty Officer 2nd Class
Joined
Nov 23, 2012
Messages
182
First order of business for boats in the yard: drain plugs out.
 
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