Go Back  Offshoreonly.com > Technical > General Q & A
Crankcase Ventilation question >

Crankcase Ventilation question

Notices

Crankcase Ventilation question

Thread Tools
 
Old 02-27-2006, 10:42 PM
  #1  
Registered
Thread Starter
 
Joyride's Avatar
 
Join Date: Jun 2005
Location: Lake Dallas, Texas
Posts: 27
Likes: 0
Received 1 Like on 1 Post
Default Crankcase Ventilation question

I just repalced the my valvecovers with cast aluminum covers from Eddie Marine. No breather vents. Oops. I'm not really much of a mechanic, and I would have hoped the mechanic at the marina that did the work would have noticed and said something. He didn't. I ran it good and hard today. Oil pressure was OK when at thottle but at idle the pressure was almost zero. I shut them down and checked the oil. The was a loud sucking sound through the dip stick, (I had created a vacuum in the crankcase) and very little oil.

Where did the oil go? Did I ruin anything? What do I need to do about ventelation?

I put oil in, and they were running fine back in the slip with the oil filler caps out.

Thanks
Joyride is offline  
Old 02-28-2006, 12:44 AM
  #2  
Registered
 
dean51267's Avatar
 
Join Date: Jan 2005
Location: Paducah, KY
Posts: 4,601
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Crankcase Ventilation question

only two places it can go, in engine compartment or in engine cylinders. I would bet it cam around the rings and was burned in chamber, check for fouled plugs, sounds like there is oil getting around rings... and a lot of it...
dean51267 is offline  
Old 02-28-2006, 02:45 AM
  #3  
Registered
 
GOODT's Avatar
 
Join Date: Apr 2005
Location: KENT ISLAND, MARYLAND
Posts: 2,675
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Crankcase Ventilation question

Originally Posted by dean51267
only two places it can go, in engine compartment or in engine cylinders. I would bet it cam around the rings and was burned in chamber, check for fouled plugs, sounds like there is oil getting around rings... and a lot of it...

dean is right, with out breathers the cylinder blowby have to pressurize the crank case and will usually blow out seals and will be sucked into the cylinder during the intake stroke, very suprised that who ever put them on looked the other way when installing ( couldnt miss it, two hoses coming from flame arestor,"where do these go??? well I'll just remove them no one will notice.... )
GOODT is offline  
Old 02-28-2006, 05:57 AM
  #4  
Registered
 
birdog's Avatar
 
Join Date: Jan 2002
Location: Batavia Oh.
Posts: 4,035
Likes: 0
Received 4 Likes on 2 Posts
Default Re: Crankcase Ventilation question

I just cant understand selling valve covers without breather holes...What are you supposed to do for crankcase ventilation ?
birdog is offline  
Old 02-28-2006, 06:09 AM
  #5  
Gold Member
Gold Member
iTrader: (2)
 
Pwrbt33's Avatar
 
Join Date: Jan 2001
Location: Brooklyn Park, Md USA
Posts: 2,123
Likes: 0
Received 1 Like on 1 Post
Default Re: Crankcase Ventilation question

You can always buy the aluminum add on vents that you have to drill a hole in the valve cover and bolt these on. Some valve covers come that way for custom set ups. Via exhaust clearance problems, shift brackets, superchargers, etc. Its not that big of a deal as long as you do put vents in.

like these...
Attached Thumbnails Crankcase Ventilation question-valve_covers.jpg  
Pwrbt33 is offline  
Old 02-28-2006, 06:30 AM
  #6  
Registered
 
birdog's Avatar
 
Join Date: Jan 2002
Location: Batavia Oh.
Posts: 4,035
Likes: 0
Received 4 Likes on 2 Posts
Default Re: Crankcase Ventilation question

I hate to take a brand new set of powdercoated Valve covers & start drilling holes in them ! Knowing how my luck is..

I need to order a couple sets...I'll call Fred & see if he can get me fixed up
birdog is offline  
Old 02-28-2006, 07:11 AM
  #7  
Registered
 
Whiteknuckle's Avatar
 
Join Date: Dec 2000
Location: Beautiful Lake St. Clair,MI
Posts: 513
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Crankcase Ventilation question

I purchased the same valve covers several years ago, and yes you have to drill holes in them to accomadate your particulair setup. I brought hoses up to the flame arrestor, but I had to purchase the Moroso rubber inserts for the holes to protect against excessive oil splash sinch the Valve covers do not have a baffle in them. Needless to say, crankcase ventilation is very important no matter how you accomplish it.
Whiteknuckle is offline  
Old 02-28-2006, 08:24 AM
  #8  
Banned
 
Join Date: Jan 2005
Location: Tri-Cities, TN
Posts: 648
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Crankcase Ventilation question

We recommend venting both covers on marine applications. You can drill a hole and use a baffeled grommet or you can have the aluminum baffled tubes welded on and use 3.5" breathers.
cstraub is offline  
Old 02-28-2006, 09:37 AM
  #9  
Registered
 
Join Date: Oct 2005
Location: Millstadt, IL
Posts: 1,888
Received 18 Likes on 9 Posts
Default Re: Crankcase Ventilation question

I have the same valve covers on my boat. And I used the tall breathers on both sides. Works fine.
jeffswav is offline  
Old 02-28-2006, 09:43 AM
  #10  
Beak botr
VIP Member
 
88Fount33's Avatar
 
Join Date: Dec 2003
Location: Cape Coral
Posts: 891
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Crankcase Ventilation question

Originally Posted by Pwrbt33
You can always buy the aluminum add on vents that you have to drill a hole in the valve cover and bolt these on. Some valve covers come that way for custom set ups. Via exhaust clearance problems, shift brackets, superchargers, etc. Its not that big of a deal as long as you do put vents in.

like these...
In a 540 would one single vent as shown in the photo be enough? Opinions Please.
88Fount33 is offline  


Quick Reply: Crankcase Ventilation question


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.