PARADOX

Older (1985) merc 350 CID mag. (300 HP) at higher RPM's (above 3500) I see oil at the starboard engine, starboard side. Not dripping, squirting out from someplace. Since the whole sides gets oilie, I can't tell where it comes from and why. Any ideas?
Help. Thx

P

BillK

P,
One thing you can do is clean it off real good, then get a bottle of leak tracing die from a local auto parts store. Put it in the oil and run it for a little while. You will need to buy or borrow an ultraviolet lamp (black light) ... it makes the die glow bright yellow and it is usually pretty easy to find the leak. A plant grow light from Walmart will work fine and is pretty cheap.

There are not a whole lot of places on a small block Chevy to leak oil. Valve covers would be first on the list, then possibly intake manifold end seals. Front crankshaft seal can make a mess, but they usually dont just start leaking all of a sudden. If something has happened to the engine internally and it has a lot of blowby, it could be blowing it out of the breathers, if so equipped. That year engine should have a pcv system I think so there would not be an open breather.

Hope this helps,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

PARADOX

It's been doing it for a while so I been running under 3500 RPM's. I do think it has breathers, there are some tubes going to the bilge area. Here ever it is coming from, it's not directly from the top area. mostly starboard side. mid to low are of the motor. I can't see it when we are running, only after I stop and open the engine hatch. I can't run while the hatch is up so it's a guess game.

P

johnny b good

Oil pressure sending unit? Oil cooler/lines?

Nova 26

Where does the dip stick tube enter the oil pan? Some seal with o-ring where they go into the pan, if it isn't there, it will leak only when running.

PARADOX

THanks Nova.

The dip stick is on the side of the block and pretty much at the top of the pan. The only time this darn thing is squirting out oil is at higher RPM's Oils goes all the way to the starboard side of the boat. (inside) The whole side is sprayed with oil.
It's got to be some preassure related leak somewhere. I cleaned it, but I can't tell where and why. I have to try and run with the hatch open and see if I can find where it's coming from.

PS: anyone finds a motor hatch (red and white) floating in the water. IT'S MINE... !!

PatriYacht

Here's a problem I had. I changed breathers to some made in China, Mr Gasket stuff. The foam insiden was too dense to allow the blowby out so the pressure pushed oil out of the dipstick tube. The oil dripped onto the seawater pump belt and got sprayed all over the side of the bilge. It's not hard to see it happen. Have someone sit in the back seat and crack the hatch.

PARADOX

THat makes sence Patri.. Thanks,, I will try.