ratman

nocigarette that motor shouldn't have a lot of blowby if its a fresh engine!
i have read that oil in the combustion chamber increases the likelyhood of detonation, i would never run a hose from the valve cover breather to the carb on a high perf marine engine to introduce oil mist into the intake tract. laz what are your thoughts on this? or any of you other engine guys

vandeano

waterbum

How about baffled grommets? Seemed to slow down / stop the oil seepage coming from my oil breathers. My next step would be been the puke tank if needed.

Panther

I'd say it all depends on the power.

I ran 500 hrs on my old motors, no detonation. I wouldn't do it on my blower motors though. Also, unless you vent the hose outside the boat that oil mist gets sucked into the motor anyway because the bildge is in a somewhat enclosed area.

I'm curious what the builders have to say as well?

Breathe Later

Smitty,

Please elaborate on th parts req'd: pistons, rings, etc. So far only my dipstick pushes out on sustained high speed runs-no oil anywhere (502 Whipple/mpi).

Regards,

Mark S.

nocigarette

you guys are awsome i found out today that one breather at the front and one at the back is a bad idea, plus my covers are too low and the breathers were lined up with the throw of the oil of the rocker. New valve covers ordered with breathers at the front and taller stacks........

SeaRay Jim

And they are sooo much prettier too!

articfriends

iTrader: (1)

Stock bore 502 pistons have fairly low tension metric rings,they tend to get blow by and high leakdown especially with a supercharger.When I still had a 502 I bought 4.470 bore j/e srp pistons that could be installed with some serious honing with a tq plate that used std american size rings,motor had decent leakdown at 100 hours but by 150 was venting like crazy out breathers,by 170 hrs right before I pulled it out to rebuild it it was leaking out every seal in motor and pushing oil out dipstick tube because leakdown was terrible. When I built 540 I used zero gap rings,had great leakdown and ring seal even at 125-130 hours when I pulled it out to freshen and upgrade. I also used ring seat compound to help rings seat faster which really worked good.Currently 540 has around 50 hours on it with no considerable blowby running 9-11 psi boost. Some guys have tried to tell me zero gap rings don't work but I wouldn't have a blower motor without them,Smitty

ratman

smitty r u running 2nd ring gapless rings? thx

articfriends

iTrader: (1)

Top rings,Smitty