2003 Yanmar, 765 hours - milky oil, overheating, evacuating coolant - SailNet Community
 
LinkBack Thread Tools
post #1 of 3 Old 05-10-2010 Thread Starter
Junior Member
 
Join Date: Aug 2006
Posts: 6
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
2003 Yanmar, 765 hours - milky oil, overheating, evacuating coolant

Hello everyone,

My relatively new Yanmar 4JH3E was unused for 3 years and has just been put back into service and has a problem: milky oil and overheating.

Before I started the engine the first time, I changed the raw-water impeller, the radiator cap, the thermostat and the pump/alternator drive belt. All the old parts were in good shape upon removal. Basic maintenance is the limit of my knowledge and ability - but I've always been good about doing it on a timely basis.

After launch, the engine overheated. Part of the overheating was evacuation of coolant: about a quart (of a total capacity of about 7 quarts) got pushed out of the engine and then the overheating happens quickly.

There is liquid in the oil - very milky. I've changed it each time as I've re-tested the engine and it gets milky again. It takes 20-40 minutes before the engine overheats (the gauge spikes to max in just a few seconds). The engine is now very hard-starting: you turn the key and there is a long pause as the starter tries to turn the engine and takes a few seconds to overcome the engines resistance to wanting to turn.

Any ideas of what the most likely problem is?
vpo3 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 3 Old 05-10-2010
Just another Moderator
 
Faster's Avatar
 
Join Date: Sep 2005
Location: New Westminster, BC
Posts: 16,518
Thanks: 104
Thanked 309 Times in 299 Posts
Rep Power: 10
     
Sounds like a head gasket... the starting resistance is likely liquid in the cylinder(s), which may be leaking past rings into the crankcase - hence the milky oil.

It needs proper attention ASAP.

Ron

1984 Fast/Nicholson 345 "FastForward"

".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
Faster is offline  
Quote Quick Reply Share with Facebook
post #3 of 3 Old 05-10-2010
Learning the HARD way...
 
eherlihy's Avatar
 
Join Date: Jan 2007
Location: Boston / Ft Myers Area
Posts: 3,996
Thanks: 157
Thanked 99 Times in 96 Posts
Rep Power: 9
 
Here is your second opinion for a head gasket. - you hope!

Have a compression test done.
eherlihy is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Yanmar baffling black smoke Tspringer Diesel 27 08-03-2012 09:44 AM
Changing Engine Oil Tom Wood Gear and Maintenance Articles 0 10-02-2002 08:00 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome