Oil Burn 135 Lehman

[asianlady]

I use a Qt of 30/40 wt every 15/20 hrs the motor has around 1500hrs. Runs good no smoke leaks. Just looking for a normal burn rate. thanks

[mike66]

That's been talked about a bit. One member reported that if he fills to the mark on the dipstick, the oil disappears a lot quicker than when the engine is a quart low ( by the mark). Guess you can try to let yours go down and carefully monitor to see if it keeps going down as quickly.

[tego]

I had twin Lehmans in my last big trawler and I had the same experience. If I kept the level about a quart low, they didn't burn any. If I topped them off (full mark) they'd go down to the qt low level and stay there. Great engines. Ben

[Steam Flyer]

In our last boat, we had a Lehman 135. Because of the angle of the engine fore/aft, the way it was installed to meet the prop shaft, the proper oil level was not the same as marked by the factory on the dipstick.

The owners manual had a diagram of the proper marking for the dipstick FOR THAT BOAT/INSTALLATION and a prior owner had marked the dipstick properly (I triple-checked). So your dipstick marking may not be giving you the right oil level.

As Ben said above, if you overfill the oil may be disappearing until it gets down a bit. This may not be doing much harm but overfilling is not good! Experiment with running the engine with the level down a quart or even 2, see if the level holds steady. IIRC those engines hold about 4 gallons of oil so it's not like you're starving it.

BTW to answer the question, taking a look in my old log, we burned about a quart every 50+ hours. Some runs I put in 2 quarts between oil changes but most I put in one, sometimes none.

The Lehman is a GREAT engine, I wish I could get one in a boat like our current one!

- Doug K
"Sugar Magnolia" Albin 31TE

[Roger and Patsy]

Overfilling can screw up an engine badly. Typical overfill problem is with a boat that has run fine at that oil level for months or years. Then it hits some nasty weather and does some heavy pitching which sloshes the oil up against the rotating crankshaft. This whips the oil up into a froth which doesn't pump very well. Just when you think you are deep in it, the oil pressure alarm comes on.

On some engines, the frothing can force oil out of the dipstick. I turned back from a nasty head sea run with the drip pan full of oil and the low pressure oil light on. Got towed in and spent several expensive days looking for non-existent engine issues before I found a mechanic who figured out what was going on. I put a new "O" ring on the dipstick, a bungy to hold it down, and refrained from putting that last little bit of oil in from the jug. Thousands of miles later, not a hint of a problem.