Mercruiser submerged up to bottom of heads.

wieland77

Cadet
Joined
Mar 29, 2004
Messages
7
I have a 1988 350 merc w/ an Alpha 1 outdrive. I keep the boat in fresh water in a shallow well. I had a leak come in through the bellows or u-joint shaft (boot) overnight and water came into bilge up to the bottom of the heads. Starter was submerged and half of alternator. After pumping out water and getting ready to take boat accross the river to put on trailer (did all in a hurry because my bilge pump quit) fired up engine and killed very quickly because milky oil was being pumped out of the valve cover breather into the air filter! Then towed boat to launch and put on trailer. I have not had a chance to drain oil pan and pull valve covers to see how much fluid is in the system. The only thing I can think of is water entered into pan from dipstick tube. <br />Sorry for lengthy question but what kind of mess do I have on my hands? What should I attack first? Thanks for any info...
 

Blk-n-Blu

Master Chief Petty Officer
Joined
May 12, 2004
Messages
821
Re: Mercruiser submerged up to bottom of heads.

wieland, get The oil and water mix out of the engine FAST use the oil pan plug to drain and change the oil filter as well,don,t bother pulling the valve covers, pull the spark plugs and crank over the motor with whats left of the starter to remove any water from the cylinders,use some cheap oil and do several oil and filter changes,When filling with oil Merc usually has oil caps on each valve cover fill from both. Then refill with proper oil and filter and allow the motor to run on the muffs for an hour or so. Residual water should boil off when you run under load for a while.<br />Your starter and alternator may survive also if you have power steering check your pump and check your fuel/water seperator good Luck
 

crwallaceva

Cadet
Joined
Feb 7, 2004
Messages
7
Re: Mercruiser submerged up to bottom of heads.

In my haste last fall I had a similar situation. I put the boat in the water and forgot to put the plug in (new boat owner forgetfullness). Anyway the boat was running when it flooded, so I cut engine. Water level got up to the bottom of heads (350 mag motor). Oil looked fine, but I flooded the trim motor and resevoir, that required doing a reman on the trim cylinders and cleaning out the resevoir. Also gimbal bearing got water in it since the boat was squatting at an angle to allow water into that area. Had to have it replaced as well. Probably should have had the u-joints replace cause I hear them making noise now-even after triple greasing them to push water out of bearing caps.
 

Tufan

Petty Officer 1st Class
Joined
Sep 6, 2003
Messages
202
Re: Mercruiser submerged up to bottom of heads.

Great advice from Blk-n-Blu. If it works you still may need to re-wire the engine and replace the starter. Once starter touches the water it does not last long. Alternator may survive.<br />I recommend having two bilge pump, even on a small boat, one directly wired to float switch and one on manuel. <br /><br />Good luck.
 
Top