I wanted to see what type of crankcase ventilation you guys are using I know Mercruiser just had vent tubes running up to the flame arrester, that just seems a little outdated and on my engines witch had a little blow-by it made a mess of the F/A and down the sides of the carbs after a long run. I'm just looking for some ideas of how you run yours ? Do you use puke tanks or PCV valve, or just breathers in the covers. I am not sure even if there is any USCG laws on how they want it to be vented. Thanks Jamie

I use PCV and a breather cap.

Puke tanks .... Clean as whistle now. Had a mess every time bbc with 177s. Soon as these were installed no more problems

Dual inlet puke tank on each motor, hose from each valve cover to the tank, works great spotless motors.

on most of all my boat engines I have switched to PCV valves in one valve cover, vented to flame arrester out of other...merc started using PCV's on the 500hp and 525SC, pretty much on all now

The K&N type filters make a mess on mine, sometimes they pop right out and make even a bigger mess before I realize it... I`m switching to these:


http://teaguecustommarine.com/em0011...-breather.html

Comverted most all the boats I have owned to PCV valve set ups. If possible hook the PCV valve to pull from the lifter valley at the front or rear of the engine. Install breathers in the opposit end from were the PCV was installed. Also plumb the breathers into the air cleaner as most cars were from the factory.

I personally don't like pumping oil residue back down my carbs, or intakes. My boat doesn't have to pass an emission inspection. Puke Tanks are a really good way to go imo.

+++ puke tanks,, or a vaccume pump plumbed to a puke tank for the bigger blower and ci engines..

IMO - if you have blow by, you need a puke tank. No sense gumming up the valve steams and tops of the pistons.

For a naturally aspirated marine application that isn't experiencing blow by I like the PVC setup to help in condensation / oil contaminates removal. Especially for those running cooler than stock thermostats that barely gets the oil to operating temperature. Also, doesn't hurt to have a LITTLE film for winter layup. Some may say it aids in upper lubrication similar to lead did back in the day while engines are loaded.

Blowers- puke tanks are a must. Vacuum pump added would be ideal.