My engine is a Yanmare 4jh2e. We recently changed the oil. We took the boat out for an hour motoring first to get the oil good and hot, then changed it straight away.
Service manual says 7 quart capacity. We had sucked 7 quarts out with a west marine extraction handpump vacuum tool. We put in 7 quarts of Shell t4 15W40. Once done, we checked the dip stick, ran the engine to make sure the engine oil was circulated, shut it down waited 10 minutes and checked the level again. All good so far.
I went back two days after the oil change, checked the level and to my surprise it was above the line.
Checking the dipstick on this boat has always been odd compared to other engines I've used. The oil forms a long v-shape along the stick, rather than a perpendicular line. The base centre of the V is where I'm guessing the "true" oil level is, rather than the high thin amount of oil up the sides of the dip stick.
So I bring back the extraction unit and draw roughly a litre or so out and once again the oil is on the line. I've never over filled oil before, but thankfully the engine hadn't been run more than 10 minutes at the dock with this amount.
Since the oil was overfilled I had concerns about the breather filter might be getting gunked up. To see if there was a lot of pressure I had my wife start the engine and warm it up. I removed the oil cap afterwards while running and observed fairly strong air pressure out from the cap opening. Here's the strange part. We put the boat in gear and put a good load on the boat eventually running around 1900-2000 rpm tied to the dock. The air pressure at the cap reduced substantially...
I've ordered up a new gasket for the breather cover, and once it arrives will pull the two bolts for the breather cover off and inspect. This way I can determine if I need to either clean or replace the oil mesh filter inside.
Questions
1) Am I the only one finding it a challenge to get a good clear reading off the yanmar dip stick? I can't think of any other motor, (car, truck, airplane, other diesel) that has been harder to get a good clear read on that I've operated in the past.
2) Does it make sense that the breather pressure would decrease when RPM's and load increase?
Service manual says 7 quart capacity. We had sucked 7 quarts out with a west marine extraction handpump vacuum tool. We put in 7 quarts of Shell t4 15W40. Once done, we checked the dip stick, ran the engine to make sure the engine oil was circulated, shut it down waited 10 minutes and checked the level again. All good so far.
I went back two days after the oil change, checked the level and to my surprise it was above the line.
Checking the dipstick on this boat has always been odd compared to other engines I've used. The oil forms a long v-shape along the stick, rather than a perpendicular line. The base centre of the V is where I'm guessing the "true" oil level is, rather than the high thin amount of oil up the sides of the dip stick.
So I bring back the extraction unit and draw roughly a litre or so out and once again the oil is on the line. I've never over filled oil before, but thankfully the engine hadn't been run more than 10 minutes at the dock with this amount.
Since the oil was overfilled I had concerns about the breather filter might be getting gunked up. To see if there was a lot of pressure I had my wife start the engine and warm it up. I removed the oil cap afterwards while running and observed fairly strong air pressure out from the cap opening. Here's the strange part. We put the boat in gear and put a good load on the boat eventually running around 1900-2000 rpm tied to the dock. The air pressure at the cap reduced substantially...
I've ordered up a new gasket for the breather cover, and once it arrives will pull the two bolts for the breather cover off and inspect. This way I can determine if I need to either clean or replace the oil mesh filter inside.
Questions
1) Am I the only one finding it a challenge to get a good clear reading off the yanmar dip stick? I can't think of any other motor, (car, truck, airplane, other diesel) that has been harder to get a good clear read on that I've operated in the past.
2) Does it make sense that the breather pressure would decrease when RPM's and load increase?
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