oil blowing out of the breater tube
 

What would cause the breather tube to blow oil out. Boat ran fine for four days straight, taking it back to pull out I put the hatch up and actually had oil on the mirror on the hatch cover.

Motor has 40 t0 60lbs of oil pressure.

Any ideas or experience with anything similar would be appreciated.

Re: oil blowing out of the breater tube
 

BLOWBY on your rings!! Blower motors are the worst for it,I've extended my breather tubes on both valve covers and put scotchbrite in them to help wick oil back to valve cover. After 50-60 hours on blown 502 it was real bad,current engine has zero gap rings to help keep ring seal/crankcase presure down under boost,still get slight amount of oil mist (has about 65 hours W/supercharger on it)

Re: oil blowing out of the breater tube
 

What engine, what weight oil, typical RPM, how many hours, compression or leakdown test results, PCV or breathers, etc. Artic's right with the blowby though. There maybe some steps you can take to mitigate it though. You may try a little heavier oil and do what you can to keep your oil temps in check.

Re: oil blowing out of the breater tube
 

I ran 2 hoses from my breathers to a puke tank. No more problems, no leaks!

Re: oil blowing out of the breater tube
 

Its a 502efi with 260 hrs on it. the breather tubes run to the flame arrestor and there has always been some oil by the tubes but I've never had anything on the mirrors of the hatch. When the motor idles now you can actually see blow by puffing out of the breather tube and the oil fill. After it idles a while it starts to run rough. I'll do a compression test tomorrow and see what that shows.

Re: oil blowing out of the breater tube
 

It could be oil/fuel. Is it real thin? Your air cleaner may be dirty and a carb problem may exist. I had it on my intake and I cleaned the arrestor and all is good again.

Re: oil blowing out of the breater tube
 

I think your idea of a compression test or even better a leakdown test will unfortunately reveal the root of your problem. If this was something like you said (always fine then suddenly this/ not something that progressively happened over time) than it's real possible you have a isue with a individual piston or set of rings. Keep us all posted,good luck

Re: oil blowing out of the breater tube
 

I also have the same problem. Mine isn't getting any worse though. Motor has approx 80 hours on it. If anything maybe a little better. Some things that might contribute this to my set up is the fact my valve covers have no baffles in them. I was wondering about just running pcv valves. I wonder if this would help? The thought of running a puke tank also was a thought. I seem to get a slight film around the flame arrestor after a days work. Probally about a tablespoon's worth. I never get any outside the arrestor though. Whats everyones thoughts on the pcv valve thing? whats the downside? Should I run this to the carb base or the intake itself? What would the downside be to doing this. As is I just spray some carb cleaner down the carb before or after a day or two of running......

BH

Re: oil blowing out of the breather tube
 

I had/have a problem with oil saturating my breather element then dripping out of the breather. Since my valve covers didn't have baffles, I tried Moroso baffle grommets instead of regular grommets. The baffle grommets are a 2 inch tube with a slit in the bottom to keep oil from spitting into the breather. I found out the hard way that the slit is not enough of a vent for a blower motor at WOT. Pressure built up in the crankcase and I blew my dipstick about 4 inches out of the tube. It sprayed about a quart of oil all over my hatch. I opened up the bottom of the grommet and converted my sealed filler cap to another breather.
Two breathers with modified baffle grommets on the starboard valve cover seemed to correct the problem. I also run a PCV from the port valve cover to the Whipple intake.

502 Mag
Whipplecharger

Re: oil blowing out of the breater tube
 

i had a problem with oil coming out my breathers because they were
mounted on the valve-covers at the rear of the engine. reversed them
to the front, and solved the problem.