About Tom Clark Expertise I can try to answer all your technical questions about installing, interfacing and repairing onboard electronics for navigation and entertainment. in addition I can answer your questions about AC and DC
electrical systems.
Experience I have over 35 years experience in troubleshooting, repair and installation of all kinds of on board electronic and electrical equipment.
Boat Repair - Posibly blown head gasket or craked block
Expert: Tom Clark - 8/19/2004
Question Hi Tom
My name is sean from Kailua Hawaii,I was resently given a 20' 1980 [Centry] inboard out board mercruser 260 v8 boat.Now this boat is over twenty years old but has never been in the water,it sat in dry storage for all this years,but was fully serviced last year by a qualified mechanic.
This is my sitcuation the motor has about 18 hours of idle time only, it runs perfect,no overheating oil pressure is 40,plugs seem fine idles at 600-700rpms and there is not any visable oil in the closed-water cooling system.But when I looked in under the valve cover,along the valve train I noticed the dredded "chocolate Milk" in small collective puddles.Though exsaminating the dip stick the oil apeard clean.So hoping that the dark milky oil in the valve covers was a resault of condensation and heavy rains while the motor was exposed,I changed the oil and filter.Then with new oil,oil filter an a oil additive to eliminate moisture "SEA FOAM" ran it for 10 min I still noticed the oil was brown.I collected oil into a glass jar to see if the water an oil would separate though brown no separation.I was wondering could this be the oil additive,and let it run longer and is it posible to get that kind of moisture threw the PCV holes on the valve covers,or if it is a more serious issue what other tests can I do.Also I was told about this product "Block Sealer" by Gunk,apperantly it fixes blown head gaskets and my freind swears by it.
Please if you can help in any way I was just about to take that 20 year maiden voyage,an I'am shure you know what owning a boat is about NO TIME NO MONEY
Thanks
SEAN MILES
Answer Sean,
It's possible that sitting for all those years that a head gasket/s or intake gasket may have deteriorated. Motor oil has additives in it to keep the gaskets soft and pliable and without having the oil on them for many years they may have broken down. The problem may only be condensation on the inside of the valve covers. If any water were leaking into the oil system all the oil would be a chocolate milk looking. You may want to drain the oil and replace the oil plug and then pour about a half gallon of kerosene into the top of each valve cover through an access hole to wash any sitting oil down to the oil pan. Next, drain the oil pan and refill the crank case with fresh oil and let it run while keeping an eye on the oil on the dip stick.
