Boat slammed into reverse going 30mph??????

[tripc]

Re: Boat slammed into reverse going 30mph??????

One of the exhaust flappers had burnt up and let water into the motor when the boat was stopped so quick..he said that the flapper was probaly like that for awhile and it was jsut a matter of time before something like that happened.. So I guess that was the iceing on the cake....

 

[friendly_jacek]

Re: Boat slammed into reverse going 30mph??????

But what caused the problem? What exactly happened?

Grrr. I hate not knowing.

page 4 from http://www.boatfix.com/merc/Bullet/01/01_13.pdf

"The normal symptom for this problem is the engine ran fine until the boater turned the engine
off for a period of time. When they went to restart the engine, it was ?locked up? or it did not
run smoothly.
1. Swim platforms and transom plate ?pockets?.
a. Rapid boat de-acceleration and then shutting the engine off on boats with either of
these can cause water to be forced back up the exhaust system. The sudden rush
of water against the boat?s transom can ?push? water higher than normal up inside
the exhaust system."

 

[jayrodoh]

Re: Boat slammed into reverse going 30mph??????

That's awesome they covered it under warranty. I was teaching a buddy of mine to drive my boat and he shut the ignition off at 35 MPH to slow down, I'm glad I didn't experience the same.

 

[fishmen111]

Re: Boat slammed into reverse going 30mph??????

Yeah, but like wow, fishmen, where did the water come from if his buddy caused this by grabbing reverse?

By the flapper being damaged...dude!

 

[enn858]

Re: Boat slammed into reverse going 30mph??????

In some of the posts here it is stated that you should not go from WOT to neutral fast - i am realy a bit worried about that - wery rarely i do that manouvre on my Mercruiser 135/alpha1 gen 2 - and nothing happens

Very rarely it also happens that i pull the safety switch by mistake (grapping a drink (cola ;-)) and by douing that the engine instantly stops as it should

If i can damage my engine duing these manouvres it must be covered by the waranty of mercruiser - eg. the safety switch is supposed to stop the engine instantly if the driver fell overboard - and this safety devise shouldent destroy the engine IMHO

I have never had any problems with my engine/drive after these - very few "crash stops" but ofcourse i do not ever go from WOT forward to WOT reverse - i only go to neutral - or if pulling the safety switch i stop the engine

Is the stearndive unit not supposed to handle these manouvres? assuming the engine and drive is in good shape (intact flaps etc)

 

[imported_TheMan]

Re: Boat slammed into reverse going 30mph??????

I might have a bit more to learn here, but then the theory is that the rush of water from the boat stopping was enough to overcome the remaining flapper, and the exhaust pressure to enter into a cylinder and hydrolock it while it was running, then breaking a rod?

Or do we have a case where the sudden switch form forward to reverse somehow caused the motor to die, then let water in with no exhaust pressure resistance. Then the rod broke during restart attempts.

This is one case where I would really like to know exactly what happened. Even though I never have, and never plan to go full forward to full reverse, it would be good to know what might happen in the event of an emergency (about to run into the Kraken and need a quick get away).

 

[paulrfrancisco]

Re: Boat slammed into reverse going 30mph??????

I would suggest that as in any accident, time tends to stand still. Where in reality, I'm sure the motor did not instantly stop... Bringing the shifter from fwd to rev will definately cause the motor to throttle down, taking exhaust pressure off of the exhaust.. Then there was no exhaust flapper to stop the in-rush of water due to the sudden deceleration and it ingested water through the exhaust valves. The engine was freewheeling due to closed throttle plate, but the prop dragging fwd in the water while it was shifted in rev, probably forced the engine to turn backwards for a few revs just before it gulped the water and stopped cold... All this took time, that seems instantanious.

 

[oops!]

Re: Boat slammed into reverse going 30mph??????

ok....long block comin......wow......lets hear it for warranty.....

but our guys here, say there is more.........

are we gonna accept the word that the drive is good?

any bets on a b3 comin as well?

 

[tripc]

Re: Boat slammed into reverse going 30mph??????

ok....long block comin......wow......lets hear it for warranty.....

but our guys here, say there is more.........

are we gonna accept the word that the drive is good?

any bets on a b3 comin as well?

I guess whten they put in the motor and take it for a test run we will know about the drive.Hopefully everything is ok with it..I am in need of some lake time soon!!!

 

[markhunting4032]

Re: Boat slammed into reverse going 30mph??????

Good luck w/ the fix. like stated earlier keep us informed. i would also like to know what he problem is/was.