Water ingestion

[shifter nut]

WELL i,m back block checked out ok....now my question is this...does my 87 wellcraft 5.7 mercruiser alpha 1 have exhaust internal shutters,,this is my first boat so I would not know. i was reading a service bulitin from mercruiser that states doing throttle chops will ingest water while running your boat on muffs......another thing i did not know...ooopppsss...my engine sucked in about 3.5 gallons of water in a very short period of time...another thing i adjusted my valves by turning the engine by hand and following the specs in my manual i may have over tightened a valve or 2[normally i would adjust with engine running].which would cause the engine to act like a compressor and suck water in if the valves arent closeing properly.....the engine ran fine until the water intrusion...like ive stated top end has been completely redone except for cam timeing chain gears.. exct...new headgaskets, heads where pressure checked, new head bolts, intake gaskets, intake bolts, thermostat, fresh water pump,new hoses,new exhaust manifolds and risers,,new risers are 4inch discharge instead of three inch,new rubber boots 4 inch.... carb rebuilt, new fuel pump..

 

[Bt Doctur]

Re: Water ingestion

almost impossable to ingest water from chopping the throttle from 1200 rpm`s. any more and the pump will overcome the water pressure and melt itself .
re-adjust using static method. rotate motor untill intake opens and closes, adjust both valves 3/4 from 0 lash, move to next cylinder.

 

[NHGuy]

Re: Water ingestion

Yes it will have shutters in the Y-Pipe. by the way, I can't imagine how the motor could ingest that much water.
Did you remove the plugs to see if there's any H2O in the combustion chambers? Or do you just think it took in that much water?

 

[shifter nut]

Re: Water ingestion

nh guy before i replaced the exhaust manifolds cylinders 2,4,6,8 had water in them..

 

[shifter nut]

Re: Water ingestion

bt doctor i,ll give it a shot thanks

 

[Bt Doctur]

Re: Water ingestion

Now if you mean water in one bank I suspect a exaust port rotted thru dumping water in the exaust manifold
flooding the cylinders. Couple of ways to find out.
1 Induce water into the engine with the spark plugs removed and see if water comes out a spark plug hole.
2 remove manifold and examine exaust ports for rust, put water in engine from a hose and crank engine over.
3 Another is to remove the head, look for a clean cylinder and piston, and remove the valves in that cylinder looking for a
hole behind the exaust valve.
Doing a friend 5.7 that had a bad miss, hole at #1 exaust valve.

 

[shifter nut]

Re: Water ingestion

i beleive the shutters in my exhaust are faulty allowing the water to back up into my engine while on muffs and useing a plastic 55 gal drum cut to fit my out drive so its getting plenty of water. i also had the water pressure cranked full blast at the time...i found out i should just cut the water on..but any how ...i bought this bought with the stern drive apart...had to replace the shifter cable and fresh water pump,,toke her out for a run with my family boat seemed fine most of the day then all of a sudden it quit running,,,tried to satrt and it hydrolocked got towed back boot started and trailered it...gotit home next day and removed the plugs out came water i suspected a head gasket so i tore it down for replacement.so i cleaned the block checked for cracks, cleaned the heads had the heads pressure checked, cleaned the intake and inspect its condition everything looked good..so i put her back together new marine gasket set, new headbolts ,new intake bolts , new thermostat, rebilt carberator, all new gaskets installed torqe to specs...got boat running ran good for a few minutes and started missing i shut her off checked oil was good checked all my water connections had a few drips tightened some clamps restarted engine cranked kinda hard ran it a few more minutes i shut off,, let it sit awhile and went to restart it it locked up ...broke nose cone off starter cylinders 2-8 full off water was told exhaust manifolds where bad so i bought new ones with risers and installed them ,,,replaced starter ..rann boat several times on muffs and drum shut it down check oil,,was a little milky figured it was from tearing her down..ran her some more, shut her down seem to be gaining oil....restarted and ran some more ,,,mikshake comeing out of valve covers where the spark arrestores would set with pvc valves when i shut motor off checked oil was all the way up stick till about 8 inches from top.. i pumped out around 3 to 4 gallons of the white mixture filled up a 14 qt drain pan .....so i was told cracked block i pressure tested block it checks out fine ....this boat is putting me threw the ringers....i just dont see a cracked block dumping that much water in the engine that fast, never got it to operating temp..

 

[shifter nut]

Re: Water ingestion

wouldnt a pressure test revel a leak in the valves....probable not with valve closed makes sense...Im gonna tear her back down and see what i can find......thanks all will check back tomarrow

 

[Maclin]

Re: Water ingestion

Running on muffs or in a barrel will not force water up thru the exhaust.

Other than a rusted thru intake manifold leaking, cracked internal cooling passages inside the block is about the only way to ingest that much water that fast.

Your last post where you asked about a pressure check showing a leaking valve makes me think you are mixing up the tests....engine compression test and cylinder leakdown test and cooling system pressure check. A cooling system pressure check will not test valves or anything else in the cylinder regarding compression. Likewise a compression test will not show a cooling system crack. Also a cylinder leakdown test will not show cooling system problems.

 

[spdracr39]

Re: Water ingestion

You can't get that much water in the oil pan from the cylinders. You have a cracked block most likely or at least a cracked head. I would not think a cracked head would let that much water in but its possible.

 

[shifter nut]

Re: Water ingestion

i didnt get my pressure tests mixed up ...i took my heads to a machine shop and had them pressure tested

 

[shifter nut]

Re: Water ingestion

Running on muffs or in a barrel will not force water up thru the exhaust.

Other than a rusted thru intake manifold leaking, cracked internal cooling passages inside the block is about the only way to ingest that much water that fast.

Your last post where you asked about a pressure check showing a leaking valve makes me think you are mixing up the tests....engine compression test and cylinder leakdown test and cooling system pressure check. A cooling system pressure check will not test valves or anything else in the cylinder regarding compression. Likewise a compression test will not show a cooling system crack. Also a cylinder leakdown test will not show cooling system problems.

READ mercruiser bulliten number 2001-13 page 5 sections 3,and 4 throttle chops and missing internal shutters..

 

[Maclin]

Re: Water ingestion

Did you pressure test the engine block cooling passages? That is one of the pressure tests that was mentioned for you to use as a diagnostic.

For water to get into the crankcase from throttle chops it has to get past the rings. Not much water would get thru. If a lot of water is in the top of the cylinder the engine hydrolocks and will not turn, and the water would have to drain past the rings to get into the crankcase and that is a slow process.

Leave out the remedial READ directive next time please.

 

[shifter nut]

Re: Water ingestion

yes i pressure tested the block the way it says to in the forums...i,m gonna tear her back down again and pull the block out send it to the machine shop and if its good i,ll rebuild complete engine if it isnt i have a vortex 5.7 i,ll put in from a box truck should work with a few mods...thanks for all ur help sorry about the read thing...