Oilwater film inside valve covers

"during winterizing i noticed

"during winterizing i noticed milky oil/water mix in breather tubes. looked in oil fill cap and had the same in cap and on head surfaces. removed both valve covers and inside valve covers coated with milky film. but no water in oil. pulled 4 plugs, looked normal. engine running great. will be checking compression next weekend. any other suggestion? engine is 350/270 hsp crusader. raw water cooled, 450 hours. thanks."

"I have two 1983 454 CID engin

"I have two 1983 454 CID engines. I have noticed the same milky substance under the valve covers. Right or wrong, my mechanic told me it was just condensate build-up that probably results from not running the engine long enough to heat up and vaporize it. He was not concerned and advised to exercize the engines more. I agreed with his recommendation because it gets me on the water more.

Chuck"

"I am no expert but i have nev

"I am no expert but i have never seen any milky stuff under a valve cover that was not a problem. can see how moisture could build up enought to cause milky oil build up. I live in FL were humidity is king and have never seen that in any of my boat engines, 7 inboards in the last 20 years.

Suspect some minimal water leak. Several places since yours is raw water cooled. first is risers and elbows, second is intake manifold, third is head but that is a remote one if good compression.

Heads have cooling water ports that get blocked off by intake manifold. if gasket leaks then you will get some water in the oil.

Drain the block, pull intake off and check it out. install new gaskets and use rtv where it is needed. this is a very cheep and easy fix. 20 for felpro intake set, if it is not the problem then you only spent 20 and got to see what the cam looks like and other stuff."

"no offence stephen, but it is

"no offence stephen, but it is very commen for marine engines to experince this, expecially the enviromentn there in at colder lattitudes. there is alot of mostiure in the air where these engines work, as you know. Chuck, sounds like your tech has it right, get out more and work them. now if the milk spreads to the oil itself, youve got a problem. and chuck, you would know if it was a problem -- OIL ANALYSIS"

"Robin, This is the same prob

"Robin, This is the same problem I had started with that looks like it has developed into a leak strong enough to cause the glycol in the antifreeze to heat up in the oil and clog the filter. Found this out thru oil analysis adn I am now dismantling the top end ...Time will tell but the oil analysis was the clincher. read this post in this forum..."

"thanks all. i appreciate the

"thanks all. i appreciate the reply. since they are raw water cooled both engines run really cool. i was told i probably have the wrong thermostats(the gages barely move off 100) and this might be causing the moisture. however, only one engine has the film. i am leaning toward an intake leak as one of you suggested. take care and happy boating.

robin"

"Motors either running too col

"Motors either running too cold, or it hasn't;t been run long and hard enough to evaporate the moisture that forms during cool down and waiting for the next run.

Jeff"

"100 is way too low should be

"100 is way too low should be 165 to 175 area.

doesnt hurt anything to pull the intake, clean it up an paint it, inspect the valley and clean up and sludge. inspect cam etc. run flat stone over gasket surfaces, get new felpro gasket set and install with rtv in the right places.

I like to use a diamond surface metal sharpening stone purchased from Lowes in the tool dept. It is a very flat surface and is very good on gasket surfaces. I use it with wd40 to lube the surface , keep clean rags to wipe off the residue as you go. put towel in the intake valley and plugged all ports in the head with rags to prevent iron particulate from entering.

This is a very cheep fix and or preventative maint item. never know if you have a slight vacuum leak or possible water leak.

also why not pull rocker covers, again if anything to inspect what is inside, clean it up and repaint them., felpro sells the good silicone gaskets with metal inserts to prevent over compression."