I Need a Drink or 2,Maybe 3

[UPSMAN]

My kids are going to be the death of me yet. I misjudged my future Son-In Laws boating skills and let him take my flats boat out for a day of fishing. It's the first time I have ever let it out of my sight without at least being on board. I took him out a couple of times and he seemed to know what he was doing. I even made him take the Coast Guard boat class. Prior to the trip, I gave him all the instructions. He assured me that he would be very careful and everything would be fine.

When he gets home from his trip he informs me that the boat broke down and he had to get towed to the dock. Says that the heat buzzer went off and he immediately turned the motor off. Waited 5 minutes and tried to crank it and it wouldn't start up.He has no clue why it over heated. Needless to say,here is what I found. Bottom two pistons on my 150 V6 Merc were melted to the cylinder walls.







This has turned out to be a $3000 fishing trip. Needless to say, I cancelled my Texas whitetail hunt. Live and learn.

[xcaliber]

One question, is he still the future son in law?
Sorry about the engine, hope you get it back to top condition soon.

[GrassyKnoll]

Man that REALLY stinks..... Sorry you had to cancel your trip...

Maybe it's time to reclassify his status to "EX-future son-in-law"..

On a serious note, what would cause that to happen?

[Normous]

Detonation is unkind to Pistons and Cylinder heads and Marine repairs are not cheap. Try a cigar with you drink(s), with all the stink around you nobody will bother you while your angry.
What happened? lack of fuel? not enough Octane? Did it go lean?

[gendoc]

definitely not a lack of cooling, normous most likely knows of this failure.
to me, merc........

[Boo]

I see broken piston rings. Detonation causes cracks or fissures in the crown of the piston. Heat seizing shows up at the skirt as a collapsed piston.
The only time I've seen broken rings is from cowbows who drive their cars like a bull ride, full tilt on start up. Yahoo!
Broken rings aren't proof of beating an engine when cold but it sure is suspect.
Sorry about your troubles Dennis.

[UPSMAN]

Guys,
Sure wish I knew what caused this failure but I have no clue. My thoughts would be a cooling failure(water pump or a plugged up intake). Engine has a special low water pick-up that is on the very bottom of the foot. He might have dug it in the mud and plugged it up. I don't know enough about EFI to speculate about a fuel delivery issue.

[8ptbuk]

Sorry for about the engine ! Appears maybe the oiler wasn't supply any oil or at least an adequate amount to the engine . Don't know if your model mercury has a reservoir tank and automatic oiler or you mix it directly into the gas . Major repair for sure !

[Waif]

Ouch!
I would not want to have been the lucky winner on that one.
A couple drinks, and he'd need to hide or get put to rowing while I skied.
Wonder what the deal is....
If not being beat on, oil pump failure maybe.
Has me thinking I need a nanny cam before anyone borrows a boat, though I have not loaned one in a long time.

[strum]

This sucks man.. In his defense it could have been just time for this to happen.
Would you have caught it in time? maybe ...did he run it too hard ?... maybe ..
did the water pump stop up ?..maybe.. This is why i hate to borrow anything.. and also why i hate to loan anything..
I hope you will let him live
This is a good time to make him help out with all tear down and rebuild.. maybe it'll teach him something.
My son called me a couple of years ago and said his transmission stopped working.. I go look ..yep ..no fluid and its burnt up ..so i check the oil while im under the hood..yep .. you guessed it no oil either..
I have preached keeping the oil changed and fluid levels checked forever to him..well he learnt that day. They say good decisions come from experience which comes from bad decisions.

[galamb]

I would put my money on a clogged carb.

The bottom two cylinders are fed by the same carb bank on that motor - no oil to the cylinders would be a top contender and would explain why both of the bottom ones only got chewed.

But hey, you could take out an insurance policy on the "future in-law", take him out fishing, even if you have to paddle, and be there when he "unfortunately falls overboard and drowns".

Cash in and buy a brand new engine with enough money left over for a couple of hunting trips

I will add, looking at the discolouration of the scoring on that one cylinder, this didn't "just happen", looks like it was brewing for a bit and just picked this occasion to finally throw in the towel - so maybe don't be too hard on him...

(ps - if you are handy enough to do this yourself the rebuild can be done for about a grand - if so inclined drop on over to marineengine.com, drop into the mercury outboard section and we can help walk you through it)

[one shot scott]

sorry man, I feel for ya. That's a lot of work and expense.

knowing nothing about marine engines, I wouldn't suspect cooling. I think you would see more damage on the other cylinders, and being the bottom two if any were getting cooled... it would be those two. I would lean more towards fuel or oil. EFI: not sure how they do their fuel delivery but the bottom is where crap would gather

marine is a whole nother ball game

[Normous]

[quote="galamb"]I would put my money on a clogged carb.
quote]
Dennis said he has EFI - Electronic Fuel Injection.

[UPSMAN]

This was a EFI 2.5 litre V6. About 10 years ago (at my mechanics urging) I removed the oil injection and started to mix the oil directly into the gas. So for that reason,I know that lack of oil was not a problem. I may never know what caused this but I still feel like it would not have happened had I been there. I'm not a mechanic but I can't believe that the fuel injectors on 2 separate cylinders would fail. Sure hoping that my mechanic will have an idea when I talk to him tomorrow. What really aggravates me is that I was planning on selling my boat and buying a duck boat with a mud motor.

[bubba]

That sure an'it any good news Dennis. Glad i have a hear sensor on my Suzuki 4 stroke 175, that cut's the engine off until it cool's down. It' also a shame you have to cancel your Texas trip.Hope all gets better...