Lehman 120 oil leaks

[meridian]

The freeze plug is actually a plug on the back of the cam shaft. That’s where the oil comes from. Maybe “freeze” is not the correct terminology in this case.

[Charlie williams]

Originally Posted by Dave_E

Hi All,


I know I've asked you before about oil leaks. I put a new oil pad in the drip tray below the engine and in several places I have oil spots (2-3" in diameter), about 3 of them AND I have oil accumulated on the starboard rear engine mount leg of the motor (where the data plate is). Shine a flashlight at the bottom of the head and I see shiny. Touch it with a clean paper towel... it's oil. I'm not loosing any antifreeze, exhaust color is like it always is. I also have streaks from the head to the oil pan say 7 or 8 of them in various places on the block. Idles and runs like a champ (never above 1800 RPM).



Anyone else ever had this on their Lehman? Input?



Dave

First, lightly snugging up the bolts around the valve cover but don't get carried away, if they are loose snug them slightly, but do not over tighten. Also Lucas has a oil stop leak stuff that I have used that actually works like magic and I have used for years. It makes the seals swell a little, however I never use it as directed, I cut the amount in half and give it a few weeks to do its work then change the oil... Discovered it many years ago and have never had anything with oil leaks after using it.

[rgano]

Originally Posted by Dave_E

OK, too many answers all saying the same thing. I'm going to take the cover off this weekend, check for flat surfaces, install a new gasket. Let you know what I find.

It only goes down with 22-inch pounds. That is a very like touch, and assumes a flat surface on the cover! It bends so easily.

[Brusky1000]

Originally Posted by RT Firefly

Greetings,
Mr. DE. Easiest thing to try is snug down your valve cover. NOT tight, snug. You may have to replace the gasket. If so, make sure the cover is not deformed where the screw holes are. Perhaps a previous owner was a bit too exuberant in fastening down the cover.

I agree, replace valve cover gasket.

[Dave_E]

Hi All,


Well we made it back from our 10 day cruise in the San Juan's. I say that because on our first 4 hour leg I went below for a first hand observation and this is what I found: At 1800 RPM the head gasket was seeping oil and water making these burning streaks down the side of the block... burning off the red paint. Could smell the burning oil.


At the end of that 4 hour run, the diaper in the catch pan below the engine was brown with oil/anti freeze. The anti freeze collected at the lower end of the pan. Oil had once again collected on the starboard aft engine mount leg. Oil level on the stick looked like it didn't move, but the anti-freeze was down to the bottom in the tank.


So... on the next leg, I ran the engine at 1500 RPM (thinking I could make it through the trip). That leg and all others (8 more hours) there was no anti-freeze loss that I could measure. There was no oil accumulated on the engine mount leg.



I have done no testing of any sort to this point. First thing I'll do is a cooling system pressure test. I re-torqued the head prior to this trip. This winter I'm going to go for a head gasket change. Any discussion is always appreciated as we learn together.


Dave

[Comodave]

I had a strange coolant leak. At the end of last season my starboard engine started leaking coolant. I filled it up several times and then put some dye in the coolant. Unfortunately with my wife having her 5th shoulder surgery I didn’t have time to follow up on it until this spring. After launching and running 1/2 mile to our dock, I had 3 gallons of antifreeze in the drip pan. I used the black light to see where it was coming from. It appeared to come from the thermostat housing. Filled it up and pressure tested it, no leaks. And so far we have had no more coolant loss. I am not sure on my next move.

[rgano]

Originally Posted by Dave_E

Hi All,


Well we made it back from our 10 day cruise in the San Juan's. I say that because on our first 4 hour leg I went below for a first hand observation and this is what I found: At 1800 RPM the head gasket was seeping oil and water making these burning streaks down the side of the block... burning off the red paint. Could smell the burning oil.


At the end of that 4 hour run, the diaper in the catch pan below the engine was brown with oil/anti freeze. The anti freeze collected at the lower end of the pan. Oil had once again collected on the starboard aft engine mount leg. Oil level on the stick looked like it didn't move, but the anti-freeze was down to the bottom in the tank.


So... on the next leg, I ran the engine at 1500 RPM (thinking I could make it through the trip). That leg and all others (8 more hours) there was no anti-freeze loss that I could measure. There was no oil accumulated on the engine mount leg.



I have done no testing of any sort to this point. First thing I'll do is a cooling system pressure test. I re-torqued the head prior to this trip. This winter I'm going to go for a head gasket change. Any discussion is always appreciated as we learn together.


Dave

While you have the head off, you should have it checked for cracks and have all the valves serviced.