Some advice - What to check / inspect

2000 Merc 40 ELPT 4s carb got slammed from foward to reverse @ maybe 1200 - 1500 rpm.

My son with his cousin driving......... both 13 yo and stoopid
.
Engine stalled and they couldn't it started - got towed to dock by Good Samaritan who got it started by pumping idle lever.

Anyway they made it to the ramp and brought it home.

I started to flush w/ fresh water and fired right up. Shroud off no knocks or pings.

Planned for tomorrow:

Check lower unit gear oil for water and metal.

Anything else before I dunk it for a test run?

Thanks.

Check the magnet on the lower drain plug for anything besides what will or should look like fuzz. If you see a chunk of any kind then an inspection needs to be made. If you do find a chunk the propshaft bearing housing can be pulled with the propshaft still in place. The reverse gear can be removed and a fairly good inspection can be made at that time.
As far as the RPM that the shift was made at, if that was indeed the correct number you probably should be okay. Just caution the boys how expensive (and season shortening) a repeat performance of that could be.
Tell 'em "Never dock a boat at a faster speed than you can afford to pay for the damage"

Decades ago I was offshore fishing out of Stuart, Florida. Back in the river by mid-afternoon and headed toward a restaurant on the water. Had just past the Test Center where I was still working. Was running a little 28' Phoenix with a pair of Chevys over Velvet Drives. Running around 32-3400 and almost ready to cross under the Roosevelt bridge when it hit me like a ton of bricks that my outriggers were still up!
Single lever controls. I slammed them down to idle but went too far and hit reverse with both inboard drives. Just barely touched the outriggers but to this day I haven't the faintest idea how the heck those transmissions ever took that kind of abuse.

Thanks for the advice. I'm going to pull the plug now.

ETA -

No water and a few small filings.

Sounds good. I'm wondering why it wouldn't start on the water?

I don't know. I was on the phone with them and stepped them through the process. Maybe they flooded it. They were at the mouth of Marblehead Harbor in the channel so I told them to start paddling.

When I was in High School, I had a 1959 Ford sedan (automatic trans).
I heard stories about how the tires scream the loudest if you roll forward
a bit then drop it in reverse and slam the gas pedal down to the floor.
Well, in front of all my friends, the transmission exploded right then and there.

I did learn from that one as I had to foot the entire bill. (and my father is a mechanic).

Hopefully, your son will learn also, given the "appropriate message".

Stoopid is not necessarily for ever LOL - and sometimes it can be fixed.

^^^
Agreed

Both son & nephew have been quite ...... err......subdued

Took it out his morning. Started fine but then very rough idle then stall on idle. Need the fast idel lever to sstart then then shift quickly into gear before it stalls. R?uns rough up to about 1800 RMP. Still gets up to 5400 WOT and 28 mph - so no change there - yet.

Thunderstorms came in so I'm at a dock in the next harbor over from the ramp [and my truck]

Looks like there's unburnt fuel in exhaust - sheen after stall. Never had that before.

When off but in forward gear prop locks in one direction only - and spins free in reverse. When in reverse gear its locked both directions. Don't know if that's correct or not.

Looks like I have some trouble shooting to do when I get it back on the trailer - for a couple of problems.

Filters are clean - no water. Fresh fuel. Primer bulb is soft. Fuel odor when cowl removed. Don't see any leaks though.

^^^^\\
Scratch the above.

Rough idle was only when engine hot. Puller UL plug again.

Water in lower unit oil and shavings on plug

When is forward gear prop can be spun back. When in reverse prop is locked both directions.

Prop & shaft can be pushed forward into gear case 1/4" then springs back.

The driveshaft housing assembly lower bolts have loosened from vibration.

I'll have to bring it home to pull apart. I'm marginally equipped pr capable working on engines [seals especially] so.

Looks like this season is over.

Dad, can I go swimming - NO
Dad, can I go to the movies - NO
Dad, can Eddy come over - NO
Dad, have you got the motor fixed yet - mmmmmmm no
Dad, can I go hang out with Eddy - NO
Dad, can I go play ball - NO
Dad, can i have pls have some gas money - NO

But DAD ! - I am 35 years old now !!!!
haven't I been punished enough for breaking your motor ????
NO



I feel your pain





](*,)

The movement on the propshaft is a concern for sure.
Good thing is that you are on top of it before it completely takes out the gearcase.
Am thinking that the RPM this happened at was a "BIT" more than the 1800 or so you were originally told.

I remember being sent in to a Johnson dealer in North Miami across from where Don Aranow's shop was.
Dealer was asking for warranty on a pair of gearcases with identical failures at the same time. (common sense kicking in yet??)
There were two gearcases, still on the engines, each with a rectangular "picture window" in the vicinity of the clutch dog.
I walked back to the mechanic instead of the dealership owner and asked what the real story was. Turns out the owner and a buddy were playing offshore racer and after hitting a pretty good wave the operator/owner was knocked off his feet while still hanging on to both single lever controls. Both went into reverse from a high RPM. The clutch dogs both headed to the happy hunting grounds.

[strike]Any ideas on repair cost?[/strike]

Nevermind.

It's a bunch.

There is terrible news from Florida this weekend about two
teen brothers missing from their capsized boat. They are VERY experienced boaters.
https://www.cbsnews.com/news/boat-that-carried-missing-teens-found-search-continues/

when, (you can't ground them forever) your boys get back into the boat,
please teach them how to survive IF they should ever find themselves in
a situation where they are thrown from the boat.
A little education may just save their lives.





.

I saw this on THT. 14year olds 19ft out of Jupiter headed to Bahamas.

I got a solid recommendation for a local merc mechanic [40 years] and will be bringing it to the marina Thurs PM.

It's good to be able to walk in that door with some amount of trust and confidence.

The fact it would not idle in neutral tells me there is an issue with the drive shaft / pinion gear also.

When I went through the manual I quickly discovered this is NOT the lower unit from years ago. It's a new beast to me.

Shift cam is in the very front and positioned between two castings - which are part of the LU drive housing pinned by the shift shaft.

I can only hope the housing hasn't been trashed.

But.......... I just found a zero hour 2001 merc 50 bigfoot for relatively cheap. Getting the serial numbers today to see if there's apples to apples between them...........

Update

With summer waning got the boat back.

There were a few things going on that caused the hard start / rough idle.

First - no damage in lower unit other than prop seals.

The engine must have taken a jolt though.... - and all three carb floats were stuck. The diaphragm plungers were stuck...

Then there was a problem with the fuel tank pickup that fell off the tank when the mechanic went to inspect is Lot's of air . So stoopid of me not to see THAT.

So I had them rebuild carbs, replace all fuel lines, new tank pick up. New Racor. LU seals, pressure test... test runs, etc.

$1,100.... ouch.

FWIW - the Quicksilver SS Vengeance 14 X 12 15 spline pressed hub prop is in classifieds for what I paid for it.